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Lobby => Head Amps, DACs, Sources, Portable Equipment Discussion => Topic started by: evanft on April 08, 2015, 11:41:15 AM

Title: Vintage R2R/multibit DAC Thread
Post by: evanft on April 08, 2015, 11:41:15 AM
Over in the all-purpose advice thread, a couple of us thought it would be a good idea to create a central thread for discussion of vintage multibit/R2R DACs. Many of us have become interested in them due to Marv's thread over on Head-Fi.

I eventually want to turn the main post in this thread into a sort of compiled list of DACs, possibly with info about inputs/outputs and sample rate capabilities. A google sheet may be needed if this becomes big enough.

At the same time we probably also want to compile a list of good USB to SPDIF converters at various price points. That could be a whole separate thread, but given the overlap in interest, it's probably better to keep it all in one.

I think it may be useful for every post with impressions to start with kind of a standard format. I can just copy and paste it into the top post along with a link to the impressions.

Sample Post Format:
Brand:
Model:
Year:
Inputs:
Outputs:
Sample Rates:
DAC chip:


Obviously, if someone doesn't know the DAC chip or full sample rate capabilities of the DAC they're talking about, it doesn't really matter, so it's no big deal if the info's not there.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: thegunner100 on April 08, 2015, 12:50:22 PM
Damn it... I just PM'd you right before I saw this. I'll have my simplified thoughts and info the on the parasound d/ac-1100 and transdac up in a bit.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: shipsupt on April 08, 2015, 04:21:14 PM
How old does it need to be to be "vintage"?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: evanft on April 08, 2015, 06:54:21 PM

I think anything that's no longer in
How old does it need to be to be "vintage"?
How old does it need to be to be "vintage"?

Meh, it doesn't really matter. The focus will probably be on vintage stuff, but if there's some cool newer multibit DAC worth talking about, feel free.


Title: Re: Vintage R2R/multibit DAC Thread
Post by: dreamwhisper on April 08, 2015, 07:17:03 PM
For some reason I thought the DAC chip in this was called a Sigma-Delta for the longest time, but I'm now aware that that's actually a third category of DAC.
But yes, the good stuff I've heard was all multibit and R2R.

Brand: Assemblage
Model: 3.1 Platinum
Year: 2001 (recapped/updated 2011)
Inputs: BNC, coax, toslink, ST optical, AES/EBU, i2se
Outputs: XLR, RCA
Sample Rates: 24/96
DAC chip: 4x Pcm1704

Cheers, sachu!
Title: Re: Vintage R2R/multibit DAC Thread
Post by: evanft on April 08, 2015, 08:00:51 PM
How does it sound?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: n3rdling on April 08, 2015, 10:48:37 PM
The Vintage DAC Bible
http://vasiltech.narod.ru/CD-Player-DAC-Transport.htm
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Priidik on April 09, 2015, 12:31:11 AM
I stayed up way too long searching eBay for dacs from that list  >:D
Title: Re: Vintage R2R/multibit DAC Thread
Post by: evanft on April 09, 2015, 02:51:32 AM
The Vintage DAC Bible
http://vasiltech.narod.ru/CD-Player-DAC-Transport.htm

If we think there is correlation between DAC chips and good sound (PCM63?) that list could easily be narrowed down.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: AustinValentine on April 09, 2015, 01:26:06 PM
If we think there is correlation between DAC chips and good sound (PCM63?) that list could easily be narrowed down.

There is, but to some limited degree. There are quite a few variables involved. Filter and output stage design can make or break these old dinosaurs. In general, Ultra-analog 20400A/PCM63/PCM1702 DACs means that *at least* the DAC itself won't be the limiting factor.

Some older DAC chips have been out of circulation for so long and/or have had such infrequent implementations that it's hard to say just what role the chip itself is playing in the overall sound (ex. the old Crystal DACs in the Angstrom 200, the PCM67 hybrid chip in the Theta Basic, Prime, and Progeny, etc).

I've spent a bit of time buying, reselling, and occasionally keeping DACs using that list. I use the original version here http://www.dutchaudioclassics.nl/the_complete_d_a_dac_converter_list/ - the site still updates it as new information comes in. Sometimes DACs that you'd expect would sound good based on their chips sound pretty rough (ex. the Denon PCM1702 DAC). Others sound decent on their own, but need mods to shore up a deficiency or tighten up the sound (ex. the Adcom GDA's). Some surprise you with just how good they are *despite* a DAC chip that's less well regarded or really not mentioned at all (ex. the Assemblage 2.6 that I heard, with it's PCM1704, surprised me because to my ears it lacked the general 1704 "syrup" or "softness" that gets mentioned around this site; the Theta DS Pro Progeny sounds great out of the box despite it's budget PCM67 chip).

I guess what I'm saying is that it's probably a good idea to stick to dealing with vintage R2R's on a case-by-case basis. That list - while a great resource - is a bit of a pandora's box.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: ericfarrell85 on April 09, 2015, 02:16:18 PM
Austin,

What do you use as transport to these vintage goodies? I can attest to the Offramp + Spectral SDR2000 as being one of the most seamless, liquid and tonally rich experiences I have had.

I have a 2nd setup coming in today, a Lampi 5, with i2s configured to the Offramp pinout. I'll need a 2nd transport for the Spectral. Have you tinkered much with transports? Short of another Offramp, I can't tell which road to take.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: AustinValentine on April 09, 2015, 02:25:58 PM
Austin,

What do you use as transport to these vintage goodies? I can attest to the Offramp + Spectral SDR2000 as being one of the most seamless, liquid and tonally rich experiences I have had.

I have a 2nd setup coming in today, a Lampi 5, with i2s configured to the Offramp pinout. I'll need a 2nd transport for the Spectral. Have you tinkered much with transports? Short of another Offramp, I can't tell which road to take.

My transport is a humble Gustard U12 + Schiit Wyrd (to a rMBP and Thinkpad Yoga).

I'm a big fan of both the OR5 and the Ciunas Converter - I've never had a comparative listen between the two, but I have it on good authority that the two are pretty damn close in quality. (Though, slightly different in sound.) That doesn't help a whole lot, unfortunately, because of the Ciunas's limited connectivity (since you're looking for i2s).

Also, perhaps the dumbest thing I've ever written on any forum: I really like the Ciunas because the LED is blue. There, I said it.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Greed on April 09, 2015, 02:55:10 PM
Austin,

What do you use as transport to these vintage goodies? I can attest to the Offramp + Spectral SDR2000 as being one of the most seamless, liquid and tonally rich experiences I have had.

I have a 2nd setup coming in today, a Lampi 5, with i2s configured to the Offramp pinout. I'll need a 2nd transport for the Spectral. Have you tinkered much with transports? Short of another Offramp, I can't tell which road to take.

If you are looking for a cheaper alternative, try the CIA Transient MKII. Though I haven't heard one myself, some have said it is pretty good. Adding the external PSU will probably benefit slightly as well.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: frenchbat on April 09, 2015, 03:32:59 PM
The WaveIO board also offers I2S connectivity on top of coax, but you'll have to work out a case and a PSU, as it is a DIY product. I'm using it along with a Sigma11 psu I got on the cheap at HF, and it's quite good with my DSPro Va.

It also significantly improved the SQ from my benchmark DAC1 HDR, bringing back the lower register, though the DS harshness stayed.

Here is the webpage :
http://luckit.biz/ (http://luckit.biz/)
Title: Re: Vintage R2R/multibit DAC Thread
Post by: ericfarrell85 on April 09, 2015, 03:38:13 PM
If you are looking for a cheaper alternative, try the CIA Transient MKII. Though I haven't heard one myself, some have said it is pretty good. Adding the external PSU will probably benefit slightly as well.

Thanks Eric, I'll look into it.

 I guess I'm looking for cheaper, but only to know whether or not I can get away with it. I was a big fan of the Audiophilleo + Aqvox when I owned it. It did wonders for lower end DAC's I owned in days past, like the W4S Dac 2, NAD, EE Mini, etc... Did little or nothing for the PWD. I suspect that a 20 year old design like the Spectral didn't give much of a shit about PC playback. If only CDP's weren't so much a pain in the ass, I'd call it quits with the SDR-3000.

*won't need i2s as the Spectral doesn't have the input
Title: Re: Vintage R2R/multibit DAC Thread
Post by: AustinValentine on April 09, 2015, 05:01:06 PM
Thanks Eric, I'll look into it.
*won't need i2s as the Spectral doesn't have the input

You might also want to check out this then if you don't need i2s input http://www.shenzhenaudio.com/melodious-audio-mx-u8-ultimate-edition-32bit-384khz-dsd-xmos-usb-digital-audio-interface.html (http://www.shenzhenaudio.com/melodious-audio-mx-u8-ultimate-edition-32bit-384khz-dsd-xmos-usb-digital-audio-interface.html). It's being floated around as a slightly better Gustard U12 alternative. I may pick one up to try out myself.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: dreamwhisper on April 10, 2015, 01:01:35 AM
I owned the Assemblage 2.7 and the Pararsound 1100HD at the same time, and they both sound 'natural'. The Assemblage has a larger soundstage and the more neutral mids than the Parasound which are a compromise because the Parasound has slightly more detail in the leading edge of transients than the 2.7. This became noticeable in bass impact and highs over time but it is a small detail.

However, the way the PCM1704 was implemented in the 2.7 wasn't ideal, since, the upgraded 3.1 (same circuit balanced) sounded much more neutral, tighter bass, less bright highs.
But I believe I'm bias to the PCM1704 sound because I like to listen to music at low volumes, and the 120 db S:N ratio seems pretty good on that chip.

I'm not really looking to replace the DAC, in fact I'd even consider buying another vintage DAC for an HD600/Dynahi rig.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: JeremiahS on April 10, 2015, 09:57:28 AM
Hello people,

I would like to thank evanft for starting this topic so we can have a more focused discussion on vintage DACs.

I just repost what I asked in the general DAC topic. These devices are very rare in where I live but I know someone who own a Parasound 1100HD but the thing is it has been modified pretty heavily. I'm not sure about the technical details but its analogue stage has been replaced with a discrete part and he also say that all the capacitors have been replaced with newer ones. I think he's upgrading to the new Hugo TT so I may have a chance to take it off his hands.

If it helps, IIRC this is the original sales ad: http://www.head-fi.org/t/548272/fs-modded-parasound-dac-1100-hd

What do you guys think, would it be a good investment? I currently have an Accuphase DC-901 DAC so maybe this vintage DAC can provide an alternative sound.

As always, I thank you for your advice.

Regards,
Jeremiah
Title: Re: Vintage R2R/multibit DAC Thread
Post by: evanft on April 10, 2015, 11:08:24 AM
I actually have a Parasound D/AC 1000 coming from Canada. I paid $236 for it, which seems like a fair price given that the 1100 goes for around $300, plus it was in great condition (it even comes with the original box). It should be here in a week or two. I ordered the Gustard U12 from Amazon.

From what I can gather, the 1000/1100 are singled-ended versions of the 1500/1600. The lower-end models have 2 lower-spec PCM63 DACs, while the higher end ones have 4 high-spec PCM63s and balanced output. The 1100 and 1600 seem to be the same as the 1000 and 1500, respectively, but with HDCD capability.

If someone wants to go for a 1500, there's a hifi shop in Montreal (http://www.audio-occasion.qc.ca/lecteurscd.htm) that has a used one listed for about US$400. I emailed them about it. They speak English and are willing to ship to the United States. With shipping, they want US$480. That's above what I would pay given its age, but maybe there's someone else who wants it.

Hello people,

I would like to thank evanft for starting this topic so we can have a more focused discussion on vintage DACs.

I just repost what I asked in the general DAC topic. These devices are very rare in where I live but I know someone who own a Parasound 1100HD but the thing is it has been modified pretty heavily. I'm not sure about the technical details but its analogue stage has been replaced with a discrete part and he also say that all the capacitors have been replaced with newer ones. I think he's upgrading to the new Hugo TT so I may have a chance to take it off his hands.

If it helps, IIRC this is the original sales ad: http://www.head-fi.org/t/548272/fs-modded-parasound-dac-1100-hd

What do you guys think, would it be a good investment? I currently have an Accuphase DC-901 DAC so maybe this vintage DAC can provide an alternative sound.

As always, I thank you for your advice.

Regards,
Jeremiah

It would depend on the price. $250-$300 would probably be good if the mods are well done and actually help the sound. But then again I'm kinda against paying more than $500 for one of these vintage DACs, so maybe my perception of its value is off.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: GoldfishX on April 20, 2015, 06:15:10 AM
I just bought the Monarchy M22A that was on Head-Fi for a couple weeks. Looking forward to posting some impressions of it and running it head to head with my Sony HAP-S1, Fostex A8 and Museatex Melior Bitstream DAC's. Also snagged an Auraliti PK90, which I'm planning to combine with my Audiophilio 2/PP, hopefully as a reliable new source (the Sony is fine for what it is, but the achilles heel is you have to use the onboard DAC...I'm hoping to improve the sound from it to some degree).

Yay for income tax checks. New toys.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: GoldfishX on April 20, 2015, 07:51:49 AM
It would depend on the price. $250-$300 would probably be good if the mods are well done and actually help the sound. But then again I'm kinda against paying more than $500 for one of these vintage DACs, so maybe my perception of its value is off.

That is how I feel, taking reliability into account for used electronics. I won't be able to afford a Yggy anytime soon (and I'm expecting a delay once they ship the initial batch anyway, due to the demand), so might as well have some fun. I'm happy to see Monarchy is still active, so hopefully if my M22A encounters any issues, they could service it...
Title: Re: Vintage R2R/multibit DAC Thread
Post by: MuZo2 on April 21, 2015, 07:09:52 PM
Anyone heard German Porta DAC 1866?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: DaveBSC on April 21, 2015, 07:53:43 PM
The old EAD 7000 is a good option for somebody looking to play with vintage R2R DACs for not much money. The MK1 used an AD1862, MK2 switched to the PCM63, and MK3 added the PMD-100 and HDCD support. Inputs are ST, optical, and coax. It's a single-ended design that uses one chip per channel. The balanced outs you see on some of them was an option, done via phase splitter.

Today they go for $400-500, and are pretty reliable. There's also a company that will do full servicing and upgrades, which is important for these old things as most of them are now old enough to require a full re-cap.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Hands on April 21, 2015, 08:16:21 PM
I'm curious, are there companies that would service old Theta DACs?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: evanft on April 23, 2015, 01:12:19 AM
I received my Parasound D/AC-1000. Here are my very early impressions and comparisons to the Modi 2. I'm using the Wyrd+Gustard U12 to connect the Parasound.

- The Modi 2 has more bass. This was pretty apparent across a range of test tracks, and even showed up when I did some fast switching between the two DACs, something that tends to obscure differences. Now, whether this is due to the Modi having goosed, north of neutral bass remains to be seen. For all I know the Parasound is simply neutral and the Modi is not. I'll have to evaluate further.

- I think I'm picking up more small details with the Parasound than the Modi.

- I think there may be less digital edge/harshness with the Parasound.

- The Parasound is fucking huge and looks like a rack server.

I'm kinda surprised with how good a piece of digital equipment from 1995 sounds.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: HitmanFluffy on April 23, 2015, 02:15:27 PM
After a Google search out of curiosity about old Theta DACs, I discovered a local dealership has recently gotten a hold of a Theta DSPro Gen V in good (fully functional) condition. There isn't a price listed but I can't imagine it costing much more than USD$1400. I reckon with the Yggy rolling out I'll be able to haggle the price down closer to USD$1200. Do you guys think this would be a good buy? I have my concerns about the machine dying of old age and if I did buy it I would have to purchase a digital interface. Thanks.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: GoldfishX on April 23, 2015, 02:29:10 PM
Me personally, I wouldn't. $1400 or even $1200 is too much to risk on vintage gear. Another $900, get the Yggy and have peace (piece? lol) of mind.

The Monachy DAC I bought is advertised as being near mint and looks stunning on the outside, but I'm prepared if it encounters an issue internally. The cost of entry was right near my limit for vintage (about $400 with shipping)

I'm going through the same thing with vintage CD players right now. So many look cool and they're nowhere near their old retail prices, but the chances are high of something being wrong with them. I imagine DAC's have fewer moving parts, so they would be more reliable than a CDP.

Someone could probably turn repairing vintage DAC's/CD players into a very profitable business.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: HitmanFluffy on April 23, 2015, 03:14:10 PM
Thanks for that. I guess I'll see what the store's asking price is. What would you peg as a sensible price for one?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: GoldfishX on April 23, 2015, 03:24:15 PM
marvey's went for about a grand and I was thinking about it hard. But again, I think a few people would have bought it for the original $1400 asking price if there was certainty over the unit's innards. Reselling a working unit and reselling a non-working unit are two very different scenarios.

But also remember, that particular DAC commands a premium both based on its reputation and its' history (aka the Mike Moffat magic touch). I doubt a Monarchy or Adcom plays in the same league, but the risk is far less.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: evanft on April 23, 2015, 05:02:35 PM
Yeah, I wouldn't drop more than maybe $700 unless I knew it had been serviced recently by someone who knew what they were doing and gave it a clean bill of health.

There's still that dealer in Montreal who has the Parasound D/AC 1500 for $480 shipped to the USA. That wouldn't be a bad way to try out a vintage PCM63 DAC.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Tachikoma on April 24, 2015, 04:51:41 AM
Well, at least the Theta Gen V isn't using anything that is truly unobtanium, like Ultraanalog chips, and if you nudge Schiit the right way, you may be able to get them to help if something does go wrong. $1200-1400 is probably OK considering market prices.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: GoldfishX on April 28, 2015, 02:16:14 PM
I received both the Monarchy M22A and the Auraliti player yesterday. Didn't have a lot of time to play with them and my USB cables/SPDIF cables are all set up for my old setup (aka, I have wire everywhere because everything is too damn long!), but once I got situated, I popped in the Magni (not exactly ideal, but it has become a decent reference point, since I know its sound signature) with the HD600 and the HD800. What I immediately noticed moving from various Delta-Sigmas is two things:

-the soundstage has gone 3D. On the HD600, I heard things all around my ears. Like, someone is coming up behind me. And this was on songs I thought I knew perfectly.

-details! instrument separation, nuances in the female voices, echo effects, percussion sections...I felt like I could close my eyes and SEE the performers. "Effortless" would be the word to describe it. Too many small intangible improvements over my other setup to describe. Even the Celine Dion songs I usually skip, it added that ethereal touch that kept my fingers away from the "skip" button. Based on that, I have a LOT of CD's to revisit.

Of course, the tone was too sharp/bright with that pairing (my HD600 is the silver driver version and the pads are worn out) and wasn't quite right, but the image itself was phenomenal. I finished hooking up around midnight and was playing with various songs until about 3am.

My plan is to eventually pick up a Yggy, but damn if this thing didn't at least set the bar pretty high for it. Also, these impressions were from the Monarchy being ice-cold...Will be curious to see if it improves after a couple days of being on.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Marvey on April 28, 2015, 11:24:48 PM
Well, at least the Theta Gen V isn't using anything that is truly unobtanium, like Ultraanalog chips, and if you nudge Schiit the right way, you may be able to get them to help if something does go wrong. $1200-1400 is probably OK considering market prices.

PCM63 chips are unobtanium. Some of the transistors on the board may also be unobtanium. The Gen V boards went through a few revisions. Mike Moffat left Theta before most of the revisions on Gen V. He was long gone when Va came out. Asking Schiit for help on something that a few of them were involved in with another company 25 years ago... that's really pushing it.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Tachikoma on April 30, 2015, 03:17:26 PM
PCM63 chips are somewhat obtainable, although there is a decent chance of getting fakes. As for transistors, unless they were extremely specific there's usually a modern equivalent? No idea re: Schiit, maybe they'll do it for the right price, maybe they won't.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: MuZo2 on April 30, 2015, 03:44:01 PM
PCM63 are available depends on which one K, KII or Y or P
Not sure about fakes, how can you make a fake working dac chip
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Ferrum on April 30, 2015, 04:02:59 PM
I owned a Ontech DAC from Denmark based on the AD 1865 chip pre usb and with no other function but DAC conversion. It had one input and one output, that was it. The product description was a bit different, 2/3'rd of the info was about the power supply!?

Never heard anything better in my life. Extremely quiet background, super resolved, bass of dreams etc etc

(http://bildarkiv.hififorum.nu/mickey/dac/P1010024-8-6.JPG)

(http://bildarkiv.hififorum.nu/mickey/dac/P1010030-8-6.JPG)

Ferrum

Title: Re: Vintage R2R/multibit DAC Thread
Post by: audiofrk on April 30, 2015, 04:29:08 PM
PCM63 are available depends on which one K, KII or Y or P
Not sure about fakes, how can you make a fake working dac chip

I think they take a reg pcm63 p and add a k
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Tachikoma on May 01, 2015, 03:07:09 AM
Who said anything about fake and working? :P
Title: Re: Vintage R2R/multibit DAC Thread
Post by: thegunner100 on May 01, 2015, 03:15:42 AM
In preparation for receiving my Yggy next week, I'd like to describe the dacs that I'm coming from. See my profile for gear, but I mostly used the V2 -> hd600.

Schiit Gungnir w/ usb gen 2 & wyrd - A fun an exciting dac to listen to. Smooth treble, solid hitting bass, and sweet mids all around. It is a dynamic dac though, so not the best for people looking for a laid back sound. It's a very good for a D-S dac. The biggest strengths of the gungnir is its tonality and lack of digititus. The biggest weaknesses I feel, is its detail extraction and soundstaging. The dac just doesn't seem to be able to extract much information from recordings as the two vintage dacs that I have. The wyrd does make a subtle difference, mostly improving in imaging, soundstaging and blackness in the background. Highly recommended dac for those who prioritize tonality over technicalities. Not recommended for use with hd800s or he-560s. I prefer to use speakers with the gungnir than headphones. They just seem to work better together.

Parasound D/AC-1100 w/ gustard u12 - My current favorite dac. Huge, but doesn't get hot. Uses 2 PCM63 chips (mine are upgraded with K grade). Extracts a ton of micro and macro detail from recordings. I never thought that the hd600s were so capable of scaling up so high. This dac has been the most significant upgrade for the past year. Aside from the detail retrieval, this dac has fantastic imaging and better soundstaging compared to the gungnir. While the bass doesn't quite hit as hard as the gungnir, it is much more detailed, well extended, and rumbles deeper. While I wouldn't exactly call the treble smooth, it is not harsh in any way. I feel like this is what a vintage R2R dac sounds like.

Sonic Frontiers Transdac w/ gustard u12 - Another excellent R2R dac, using PCM1702. It has a very smooth and somewhat warm tone to it compared to the gungnir and parasound. It's not as detailed as the parasound, but maybe on-par with the gungnir. It's hard to say, I've never directly compared the two. Overall while I like what it does for the bass, it doesn't do enough of the other technicalities. For its size and price, It's very hard to beat as long as you pair it with the right amp and headphones. Opamps can be rolled on this dac btw, allowing you to trade some bass performance for some more clarity and soundstaging.

I think Marv was spot-on with his generalizations of PCM63 and PCM1702, especially concerning these two vintage dacs.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Marvey on May 01, 2015, 07:15:04 AM
And then came PCM1704. Where current R2R got it's reputation of being warm, smooth, but lacking in pace, attack, and resolution.

BTW, the HD600 will keep on scaling. I picked up an HD650 because of what Yggy could do with traditional dynamics and a good tube amp.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: kothganesh on May 01, 2015, 07:58:55 AM
Marv:

Need a good tube amp for my HD800 and Yggy. Have the BH Crack and my one and hopefully only ZD prototype. What in the EC stable would you recommend or should I wait?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: thegunner100 on May 01, 2015, 01:05:26 PM
I'll be sending my transdac to Hans after I get my Yggy, for him to get some impressions and comparisons to his latest NOS dac and the theta gen v-a.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: GoldfishX on May 01, 2015, 02:06:55 PM
Parasound D/AC-1100 w/ gustard u12 - My current favorite dac. Huge, but doesn't get hot. Uses 2 PCM63 chips (mine are upgraded with K grade). Extracts a ton of micro and macro detail from recordings. I never thought that the hd600s were so capable of scaling up so high. This dac has been the most significant upgrade for the past year. Aside from the detail retrieval, this dac has fantastic imaging and better soundstaging compared to the gungnir. While the bass doesn't quite hit as hard as the gungnir, it is much more detailed, well extended, and rumbles deeper. While I wouldn't exactly call the treble smooth, it is not harsh in any way. I feel like this is what a vintage R2R dac sounds like.

Yup. same deal with the Monarchy. The Magni is known for being a bright amp and that treble that comes from it doesn't let me get away with indiscriminately pairing it with headphones, like my HAP-S1 did. There is a huge wad of 3K/4K glare, but I'm confident it comes from the Magni. It's pleading for a more musical, warmer amp. Weekend fun...

It may be placebo, but I've had the thing on since Monday (there is no on/off switch...it turns on when it is plugged in) and I think the imaging has tightened up a bit. It feels more centered and defined.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Marvey on May 01, 2015, 02:51:57 PM
Marv:

Need a good tube amp for my HD800 and Yggy. Have the BH Crack and my one and hopefully only ZD prototype. What in the EC stable would you recommend or should I wait?

How much money you got? :-)
Title: Re: Vintage R2R/multibit DAC Thread
Post by: kothganesh on May 01, 2015, 04:33:15 PM
3 - 3.5 grand.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Marvey on May 01, 2015, 05:04:36 PM
There's stuff coming out. Maybe the upcoming ZD Super.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Clemmaster on May 01, 2015, 05:19:33 PM
And a new website?  :)p7

Looking forward to hearing the BW at the West LA meet! Hope it is not as bright as the 4-45.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: kothganesh on May 02, 2015, 06:57:36 AM
There's stuff coming out. Maybe the upcoming ZD Super.
Actually, how much do I need ? :)
Title: Re: Vintage R2R/multibit DAC Thread
Post by: HitmanFluffy on May 02, 2015, 12:54:07 PM
I finally got around to trying out the Theta DSPro Gen V I mentioned earlier in this thread at the dealer. Oh. My. God. Its better than I imagined. I can't go back to the D-S stuff I was trying out weeks before. He stuck the price at the equivalent of about $1650 so I figured I may as well save a while longer for a Yggy. Thanks guys for the advice.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: MuZo2 on May 07, 2015, 09:06:09 AM
Anyone with PARASOUND 1600 HD can they compete with lets say GO V2+ ?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: jjacq on May 18, 2015, 12:00:08 AM
Hello guys, I'm quite new to r2r DACs and I just got a deal for an ADCOM GDA-700 for ~$270 in the mail right now. Let's hope it's a good match for my upcoming Liquid Carbon (or my current NFB 15.32) and the LCD-X.  :)p2

Brand: AdCom
Model: GDA-700
Year: Maybe 1996?
Inputs: AES/EBU, Optical, 2 Coax
Outputs: RCA and XLR
Sample Rates: 32/44.1/48 kHz
DAC chip: 2 Burr-Brown 1702
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Za Warudo on May 30, 2015, 08:16:03 PM
I bought an Angstrom 200 DAC/Preamp, designed by Mike Moffat.  Does any know what kind of chip this uses?  Is it R2R?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: AustinValentine on May 30, 2015, 09:53:26 PM
I bought an Angstrom 200 DAC/Preamp, designed by Mike Moffat.  Does any know what kind of chip this uses?  Is it R2R?

Nice pickup! I keep considering picking one up myself.

The setup of the Angstrom 200 is...well...a bit complex. It employs both R2R and Multi-Bit chips (DAC8143 & CS4328-KP).

It uses 6x daisy chained AD DAC8143 chips (http://www.analog.com/media/en/technical-documentation/data-sheets/DAC8143.pdf), which are 12-bit R2R. Then it uses 3x Crystal (Cirrus) CS4328-KP chips (http://www.wolumen53.com/pdf/CS4328-KP_Crystal.pdf), 18-bit /multibit Delta-Sigma.

Title: Re: Vintage R2R/multibit DAC Thread
Post by: Za Warudo on May 30, 2015, 11:53:01 PM
Nice pickup! I keep considering picking one up myself.

The setup of the Angstrom 200 is...well...a bit complex. It employs both R2R and Multi-Bit chips (DAC8143 & CS4328-KP).

It uses 6x daisy chained AD DAC8143 chips (http://www.analog.com/media/en/technical-documentation/data-sheets/DAC8143.pdf), which are 12-bit R2R. Then it uses 3x Crystal (Cirrus) CS4328-KP chips (http://www.wolumen53.com/pdf/CS4328-KP_Crystal.pdf), 18-bit /multibit Delta-Sigma.




Interesting.  I wonder which of the chips it uses for just stereo DAC function instead of all of those chips for its DSP.  I'm going to keep it on to see if it benefits from warm up.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: kothganesh on May 31, 2015, 02:06:56 AM
Nice pickup! I keep considering picking one up myself.

The setup of the Angstrom 200 is...well...a bit complex. It employs both R2R and Multi-Bit chips (DAC8143 & CS4328-KP).

It uses 6x daisy chained AD DAC8143 chips (http://www.analog.com/media/en/technical-documentation/data-sheets/DAC8143.pdf), which are 12-bit R2R. Then it uses 3x Crystal (Cirrus) CS4328-KP chips (http://www.wolumen53.com/pdf/CS4328-KP_Crystal.pdf), 18-bit /multibit Delta-Sigma.



AV, meaning to ask you this...youmentionedthat some mods to the Adcom 600 really help. Do you know what they are? Thanks
Title: Re: Vintage R2R/multibit DAC Thread
Post by: AustinValentine on May 31, 2015, 02:40:27 AM
AV, meaning to ask you this...youmentionedthat some mods to the Adcom 600 really help. Do you know what they are? Thanks


Definitely! This thread from Polk Audio here (http://forum.polkaudio.com/discussion/97185/the-adcom-gda-600-modification-thread) covers all of the cap and opamp modifications. (The associated Audiokarma thread is here (http://www.audiokarma.org/forums/showthread.php?t=92160&highlight=modding+an+adcom).)
Title: Re: Vintage R2R/multibit DAC Thread
Post by: rb2015 on July 12, 2015, 02:19:28 PM
I posted this over on another thread - but is might be better here:

Couple of DACs I've had success with:  The APL NWO and recently a heavily modded Lite DAC60.

Now the NWO is $20K+ but the Lite DAC60 with mods (most important Mundorf Supreme Silver/Gold/Oil coupling caps and better tubes '75 HG 6N23p are my favorites) - is very competitive.  Stock excellent for around $600 + another $500-$800 in mods outstanding!

A few features on the DAC60:

True R2R PCM1704K 24bit ladder DAC chips.
True (not an opamp buffer) 6922 tube output section
Separate PS for Analog and Digital Sections

Here is the thread I started on Headfi for the mods:
http://www.head-fi.org/t/740362/lite-dac60-pcm1704-r2r-tubed-dac-mod-project

This thing is sooo sweet sounding, yet detailed and resolving, extended tight bass and wide and deep sound stage.  The best is the rich natural tone - I listen to this for 8-10hrs a day in my office system.  Just captivating.  Better then any SS DAC I have heard yet.

Feeding it with a modded Melodius MX-U8 (Audio Sensibilities silver ref 1.5M RCA SPDIF), custom dedicated iCore 5 WIN7 Pro music server.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: rb2015 on July 12, 2015, 02:20:52 PM
Some other good info on different DAC designs:

Here are some great articles that explains Resistor ladder DACs vs the sigma-delta and multi-bit newer designs.  All have issues.  The R2R's are very expensive and difficult to make, the S-D have major filtering issues and the Multi-bits have on silicon opamps.

http://www.mother-of-tone.com/conversion.htm
http://funwithaudio.blogspot.com/2012/01/today-in-electronics-everything-is-made.html

With the DAC60 you do give up a few things - like no I2S input, no DSD native processing (I use Foobar conversion to PCM), and limit to 96K sampling and 24 bit depth.  But how many folks have 192K - true Ultra Hi Res downloads?  Or true (not resampled) DSD files?

What you get is amazingly detailed and smooth sound.

Some of the very best DAC's use R2R ladder DACs - like Audio Note, Total DAC, MSB, Audio-gd (Master 7 - uses the same PCM1704 but twice as many), Zanden, etc...
Title: Re: Vintage R2R/multibit DAC Thread
Post by: LarryHo on July 16, 2015, 04:58:35 AM
Find something has PCM1702 or PCM63 there. IT's classic.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Marvey on July 16, 2015, 05:30:26 AM
Agreed. PCM1702 and PCM63 > PCM1704.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: madaboutaudio on July 20, 2015, 06:08:21 AM
Agreed. PCM1702 and PCM63 > PCM1704.

Even Ken Ishiwata of Marantz shares the same view:

See 5:08 onwards
http://www.youtube.com/watch?v=A2QPePifDQI
Title: Re: Vintage R2R/multibit DAC Thread
Post by: lukeap69 on July 20, 2015, 09:14:22 AM
Thanks for sharing.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: madaboutaudio on July 30, 2015, 12:59:37 AM
Interesting article with notes on sound quality changes on his mods:
https://sites.google.com/site/computeraudioorg/mdht-havana-dac-modifications

Quote (selected)
Upgrade Summary - Total 54 parts upgraded

-PCM56P-K grade chips x2 - classic NOS Dac sound and increased extension
-R-Core x1- increased impact and clarity across the spectrum
-Jupiter Caps x6- incredible lush textured sound but still clear presentation throughout
-ELNA Silmic and Silmic II x25 - electrolytic caps throughout - sound stage depth/width
-Shinkoh Tantalum resistors x6 - transformed the Dac into a different beast, now I can hear the harmonics of the tube. The music swings as it should, shimmer and sheen without glare. Shinkohs seem to remove the electronics from the music.
-Schottky Diodes x8- enhanced the character of the Shinkoh resistors a must have to get the full potential of Shinkoh
-Auricaps x5 -  improved texture throughout the frequency range
-Hi-Fi Tuning Supreme fuse x1- provided more energy and impact




Misc. Tweaks
Silver Power Cord with Furutech ends vs. a standard copper 12ga cord.  The Silver cord was a bit brighter and the copper cord gave more of an organic textural sound. Liked copper better.
Black Diamond Racing cones both ways, the low-end texture was gone and the high-end details stood out more. This took away the rich tubey character imo so I decided to go without the cones.
1.5" thick wood platform under gave me a nice solid foundation to the lows which seemed to enhance the low-end texture.
Small weight on top tightened up the sound throughout the spectrum a must try for everything imo just to listen for a benefit.
Removed caps [C5 and C25] which are only used for the "stability of the circuit under critical conditions" the sound became thin sounding so I put them both back. Edit: with the new r-core in place, removing these is a MUST, with them in place the sound is severely constrained.
Bypassed the fuse with a piece of copper solid core wire. Nice improvement with overall speed and impact, was too chicken to leave it in place and returned the fuse. I might put the wire back in place though.

Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on July 30, 2015, 08:59:11 AM
Possibly Philips' last multi-bit DAC effort (TDA1387 and TDA1545, both same except the former is I2S and the latter is EIAJ) is a source of "hope" for multi-bit resurrection (at modest cost).

Not a bad DAC from my experience (Monica DAC from DIYParadise.com) ... but you need a very good output section!

That DAC is only 8-pin and SOIC sized, so no wonder its popular in DIY.

Philips made LOTS of them in the late 90s for use in certain SoundBlaster cards. Judging from eBay and Alibaba, the Chinese seem to have acquired a huge stash (you can buy a single chip for $2-3). (Chinese have huge DE-SOLDERING/DISASSEMBLY factories!)

Seems certain Chinese opportunists have already put out some ready-to-go D/As (USB, etc.) based on this now-ancient Philips chip.
 
Google "Eight parallel 8X TDA1387 Hifi DAC Hifi Decoder USB digital input " for some insight.
Note the use of MULTIPLE MULTI-BIT architecture ;)
(http://www.diyaudio.com/forums/blogs/abraxalito/attachments/1522d1421369717-tda1387-octal-dac-looks-like-good-modding-base-tda1387taobao.jpg)

$100-130 for most of these TDA1387-based D/As.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: BassDigger on July 30, 2015, 02:25:06 PM
Aha!! At last, I've stumbled upon a thread that reeeeally piques my interest.
I haven't read through it, yet. But I will be doing so (when I've the time). Oh yes, I will!!!

My addition:

Brand: Cambridge Audio
Model: DAC 3 (Original version, but heavily modified)
Year:...err...1989....I think. (Modified 2012)
Inputs: S/PDIF coaxial + dedicated SD card player multi-purpose I2S/power combi
Outputs: Original RCAs variable and fixed (never tried them) + New RCA outputs (from tube output stage)
Sample Rates: up to 48kHz
DAC chip: TDA1541S1 x 4

That's my 'baby'!
Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on August 29, 2015, 10:33:43 AM
I don't understand the CONTEXT of this thread...

Is it about stand-alone D/A processors, or the DAC chip (IC) itself?

Context makes a difference because (e.g.) SPDIF is a pretty big hit (in the negative direction) in terms of sound quality.

Is there another thread of related topic(s) ... such as multibit/R2R vs. single-bit vs. Delta-Sigma?

It's not just a matter of multibit/R2R (DAC architecture) when it comes to that classic (vintage) device's digital-sound characteristic. Many of the heavy-hitters from those days (Meridian, Theta, Wadia, Krell, etc.) used their own DSP-based digital filters --that was a MAJOR selling point. In addition, of course, there was output section and PS/regulation. Etc.

Coming back to modern times -- roughly late 1990s, henceforth -- when D-S (off-the-shelf DAC chips) were SELECTIVELY being used by folks like Meridian (they used Cirrus D-S 439x series), one can't really nail down multibit/R2R wholesomeness/goodness on DAC architecture. Many of the modern "high-end" units from Meridian, Boulder, Linn use $3.00 D-S dacs (chips) -- "encapsulating" them with optimized topologies (digital filter/upsampling; I/V and output stage; PS and regulation; RF/EMI shielding). And YES: these modern high-enders -- as $$ as they are -- not only sound (subjectively) as good/better than best multibit Thetas and Mark-Levinsons and Sonic Frontiers from the '90, their MEASURED (objective) performance blows away the antiques.

Bottom line:
High-end audio is supported by folks that have "high-end" incomes--the gear in Stereophile and TAS. And its not like those folks don't know (or don't want) the best sound.
If multibit/R2R was as good as some tout it is (and/ or D-S was "so bad"), major high-enders -- like Meridian, who do have $$ and political power --  would have pressured the semiconductor industry at AD, TI/BB, Philips, Wolfson, et al. to either produce/stock (incl. new-old-stock) multibit/R2R or improve D-S. (see **) They seem to have done the latter as they all abandoned multibit/R2R. ESS -- by their own claims -- seem to have licked some of D-S' inherent "problems". The latest DAC (ICs), like the new ones from AKM, with very good implementation (that's important) should allow one to attic those heavy, hot-running R2R antiques ... of course, bored "audiophiles" with plenty o'$$ and time-to-kill on eBay or Audiogon will always find 'scuses to justify their "superior" (classic n' good)  devices ;) ***


** This is what happened in the early days of digital audio. The high-end community didn't like the sound of early CD players, so Philips, Sony, etc. improved their designs. Not just that but modders of OEM (Meridain, Mission, etc) further improved on the overall strategy. I.e., oversampling, better I/V + output filters, etc.
Similar thing kinda/sorta happened when MASH/Bitstream (i.e., early/mid 1990s single-bit) DACs were being used by the majors. (Not so good sounding, so DAC manufs. intro'd D-S).

*** Pressure from classic-obsessed fanboyz are what make those old absurd, polluting clunkers comin' back, time and again, into modern cinema ...
(https://upload.wikimedia.org/wikipedia/en/6/61/Transit_(2011_film)_poster.jpg)


P.S. What about that Stax CD player or the M-L no. 30?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: BassDigger on August 29, 2015, 11:17:27 AM
I don't understand the CONTEXT of this thread...

Is it about stand-alone D/A processors, or the DAC chip (IC) itself?

 ahoy  Maybe you should read the first post. http://www.changstar.com/index.php/topic,2278.msg62421.html#msg62421 (http://www.changstar.com/index.php/topic,2278.msg62421.html#msg62421)  facepalm
Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on August 29, 2015, 12:15:17 PM
ahoy  Maybe you should read the first post. http://www.changstar.com/index.php/topic,2278.msg62421.html#msg62421 (http://www.changstar.com/index.php/topic,2278.msg62421.html#msg62421)  facepalm
That was the FIRST post I read, toots ;)
it seems to suggest the stand-alone units (no source or xport). In this, the correct nomenclature to use is D/A processor ;)
The acronym "DAC" can refer to ... a chip or D/A section of a device or D/A processor.
This is gettin' anal, I know, but after going thru several pages in this thread, the thread-starter post loses its context ... not that that was anything 'pecial to start with ... and, then, you get to my whacky post above: and, henceforth, any sane person feels like they're in 'Nam ')
Title: Re: Vintage R2R/multibit DAC Thread
Post by: madaboutaudio on August 29, 2015, 02:07:06 PM
Delta sigma was favoured over r2r dac not because it sounded better but because it was easier to manufacture:


http://www.head-fi.org/t/701900/schiit-happened-the-story-of-the-worlds-most-improbable-start-up/3045#post_10944447
Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on August 29, 2015, 04:16:29 PM
IMPLEMENTATION is most important.
Use of D-S or R2R dac chips may be the lowest common denominator.
Just look under the hood of Gen.V, Wadia, Mark Levinson, Sonic Frontiers, Meridian, Krell, etc. There's a lotta tight PS regulation, bypassing, careful PCB layout, low-noise techniques. Probably much more so than any Schiit, or M-F or Cambridge or  NAD made today. (Yeah: A manuf . can use a good chunk of what the customer pays for (the end product) to tweak and polish. You simply can't do that at LHLab's or Schiit's or NADs price level. So if on eBay you pay little for vintage high-end R2R D/A processor, and it's working fine, you got yourself a nice device that may very well be better than much modern gear at the same $$. The problem is: how many folks get to hear MODERN high-$ Sigma-Delta, like that $15K Meridian, or $25k Boulder? )

My comment about modern DACs (DAC ICs) measuring better is a red herring -- it was meant to be. Recently looking at a classic Stereophile review from 1993 -- several CD players compared -- the best measuring (but worst sounding) was a Marantz Bitstream unit; the best sounding (MSB) was a souped up Philips OEM, using classic 80s-era multi/R2R SAA7220+TDA1541A.
I do have several multibit/R2R goodies in my possession. Most are OEM Philips CD player mods. And these do have super sound (better than any CDP, sound card, DAP or D/A processor in my collection that incorporate D-S, which are mostly mid-grade jobs like Asus Xonar sound cards or Oppo disc player).
That said, and as noted in the beginning, the multi/R2R jobs are quite tricked out: CD players with discrete-component I/V+output section, no less than 20 indiv. power regulators., outboard PSU, etc. Not unlike the situation w/the Gen.V (and similar vintage D/A processors that are generating interest again).

Hmm... I have a theory about that ... other than the boredom hypothesis noted earlier.

Say you're an audio geek, always searching for "great" sound. You spot a deal on eBay -- a classic multi/R2R -- and win the bid for several hundred $$. It ain't a very good processor by its original reputation, but because you've ALREADY spent your hard-earned $$ on it (not to mention the time/effort of bidding, unpacking, setting up for listening), you're prone to the Sunk Cost Fallacy:
https://en.wikipedia.org/wiki/Sunk_costs
Hey, it's not your fault -- it's evolution, meant for survival...man vs wild ... Bear Grylls.
IAC, I'm not sure classic multi/R2Rs were the only game in town BACK THEN...
Recall the Optimus CD3400 portable CDP from Radio Shack, made 1993-94. It STILL sounds and measures great, but it's DAC (chip) is 1-bit. It's not that it sound better/worse than my best R2R or best D-S ... it's a very different (euphonic) sound that some suites certain moods or music genres. Makes no sense, huh???
Title: Re: Vintage R2R/multibit DAC Thread
Post by: madaboutaudio on August 29, 2015, 09:09:24 PM
I don't think buying a vintage (sd or r2r) dac is worthwhile especially in 2015, you have tons of really good sounding and high price to performance dacs in the market.

Vintage dacs don't have modern support for USB and may have problems with bad capacitors or oxidation. Also the electrical engineering measuring tools and high performance DSP/FPGA we have now is something that don't exist  back then.

Why buy something vintage when you have good modern r2r dacs from Schiit and Audio-gd with good warranty and support.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on August 30, 2015, 01:45:44 AM
Vintage dacs don't have modern support for USB ...
Yes, well-done USB is quite a bit better than SPDIF. Yet folks that are so enraptured with this vintage R2R bug that's going around seem not to comment (or notice) on that. Indeed, even when the vintage (outboard) D/A's first came to market, many reviewers noted the Achilles Heel (SPDIF).
It's possible that vintage D/A are so good, even by today's stds, that even with the SPIDF setback, they edge out modern D-S ...
... hmmm ... will it be multi/R2R + SPDIF or D-S + USB ???
But what about the other gorilla in the room: high-end CDPs (Krell, Naim, Meridian)? ... they have R2R but are not afflicted with the SPDIF issue.  Yet I don't see them mentioned very often nowadays ... CD too old-fashioned ... or is it "yuch...optical discs -- they can't be as good as jitter-free Flash playback"???
Title: Re: Vintage R2R/multibit DAC Thread
Post by: haywood on August 30, 2015, 02:34:00 AM
Yes, well-done USB is quite a bit better than SPDIF. Yet folks that are so enraptured with this vintage R2R bug that's going around...
You had me until "well-done USB".

Modern r2r dacs that are competitive with the best vintage dacs are a relatively recent phenomenon, and this thread predates most of them. I wouldn't spend a lot on one, it'd be kinda foolish to drop $1500 on a Gen V when Gumby is cheaper, has a warranty and ranks higher on the messiah-o-meter, but I wouldn't discourage anyone if they got a great deal on an old Theta, Spectral, Transdac, etc.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on August 30, 2015, 04:52:31 AM
Modern r2r dacs that are competitive with the best vintage dacs are a relatively recent phenomenon, and this thread predates most of them.
You can't really make a bold claim like that with only Schiit products as examples, dude.
I do realize that this forum/site is equivalent of a Schiit fanboyz network, but ya'll do 'em no favors by unexamined day-in/day-out manufacturer grandstanding!
What Schiit is doing -- using modern "multis" like AD5781, which was not designed for audio -- has still to be accepted by the audio community at large.
Bottom line: too early to tell.
And we may never be able to tell ... why? Because the latest D-S chip design (optimized for audio), like ESS or AKM models, are also progressing.
The more attention this area of audio science receives the better -- that gets the decision-making CEOs of semiconductor firms to add more funding to audio R&D.
In a way, the resurgence of vinyl puts the same pressure on DAC manufs ...
Title: Re: Vintage R2R/multibit DAC Thread
Post by: bixby on August 30, 2015, 05:03:04 AM
I do think that the Schiit designs have been accepted, no waiting for a tribunal to concur.  I have heard 3 of them in a number of sessions and was impressed.  And a number of well regarded members (by me of course) have bought or placed orders.  That being said, I know a good friend who just bought a Gungnir DS and it will be replacing his $12k dac bridge combo.  Of course he has no idea of the MB Gungnir nor does he care.  He likes the Hydra Z and the Regular Gungnir so much.

And THAT is what it is all about, yes?

As for the CEOs of chip companies, they are no different than any CEO, they are just looking to sell millions of chips to whomever for whatever application as long as it brings profits.   They have no allegiance to what we want.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: frenchbat on August 30, 2015, 08:23:23 AM
Paras1te do you have a point to make or are you just raving on like a mad man ?

Seems like you need to get the hang of this place before going on like this. CDPs are discussed, usb vs coax vs aes vs I2S are discussed, TT are being discussed, and you seem to have missed that completely.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on August 30, 2015, 09:11:09 AM
Paras1te do you have a point to make or are you just raving on like a mad man ?

Seems like you need to get the hang of this place before going on like this. CDPs are discussed, usb vs coax vs aes vs I2S are discussed, TT are being discussed, and you seem to have missed that completely.
Oh ... uh ... I'm ... uh... sorry ... if I ...uh ... like, so totally, like offended someone, toots ;)

About those other PUTATIVE discussions ... well, it's easy to toss a few UN-LINKED references like that.
But guess what, toots ... youz don'tz defend the troopz shooting blanks.

Oh, and ... (http://www.changstar.com/index.php?action=dlattach;attach=1982;type=avatar) ... uh one more thing ...
https://www.youtube.com/watch?v=IDDEpnjgTyw

(luv your avatar, frenchy... xxx, Miley)
Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on August 30, 2015, 09:26:49 AM
As for the CEOs of chip companies, they are no different than any CEO, they are just looking to sell millions of chips to whomever for whatever application as long as it brings profits.   They have no allegiance to what we want.
Yup ... it's all about $$ and corporate greed. Look at the big 3, or 2008 meltdown.
Got it!
Nah ... CEOs don't own Mark-Levinsons or Jadis. They could care less about low-grade chips in THEIR gear ...
...and now we return to more Democracy Now! where Amy Goodman will talk to UAW leaders about improving worker wages.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Priidik on August 30, 2015, 09:31:15 AM
multis" like AD5781, which was not designed for audio -- has still to be accepted by the audio community at large.

Dacs with S-D chips have been accepted at large and how good are these?
Some are acceptable, but most are sub-bar performing.
On top of everything let's say S-D has potential, but look what it takes to squeeze it out. 8+chips in parallel per channel in some good sounding units, manufacturing costs perhaps going over some good r-2r retail price for maybe roughly the same performance.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: madaboutaudio on August 30, 2015, 10:21:08 AM
D-S done right can sound really decently good. Many have high praises for Schiit Gungnir V1, Nad M51 and Matrix X-sabre.

However there's a reason why Schiit introduced the R2R upgrade for the Gungnir. Because R2R done right will exceed what D-S can offer but will cost you at least 1.5 to 2x more in price. Take for example Audio-gd's NBF-7 and Master 7. Both have exact same chassis, powersupply and etc. Only difference is the DSP+8xPCM1704UK vs ES9018S.

S-D Modulation is a lossy/approximation of the original values.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: frenchbat on August 30, 2015, 10:39:49 AM
(click to show/hide)

So no point, and you want me to work for you. That's what I thought, you don't understand this place. Lemme guess, you got banned from hype-fi and you thought you'd find kindred souls here, right ?

We try to keep a high SNR here, right now you're just noise.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: ultrabike on August 30, 2015, 05:26:47 PM
S-D Modulation is a lossy/approximation of the original values.

So is R-2R.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: madaboutaudio on August 31, 2015, 01:00:41 AM
So is R-2R.


No system is perfect(R2R has it's own set of problems too), but S-D is much more destructive(delta modulation), more music information is lost. Although some will argue that it is not discernible degradation, but there are many well reputed audiophiles and dac designers that will tell you that well implemented R2R Dacs sounds better than well implemented S-D Dacs.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: ultrabike on August 31, 2015, 01:36:48 AM
I don't think S-D is much more destructive than R-2R. S-D is a little more unintuitive perhaps.

R-2R appoximation will depend on error in resistor values, current sources and perhaps switching glitches (among perhaps other things). There will also be noise limitations. Errors and non-idealities can result in a non-monotonic output to code word curve, which is not good.

From what I've read, there are grades of performance with-in a single R-2R devices (consider the PCM1704U < PCM1704U-J < PCM1704U-K). This maybe due to process and dunno if device differentiation is due to cherry picking or what. There are papers here and there to deal with R-2R issues. Here is one which I have not completely read but after quickly going through it seems reasonable:

http://liu.diva-portal.org/smash/get/diva2:559515/FULLTEXT01.pdf

It is possible that some folks feel a well implemented R-2R sounds better than a well implemented D-S. But I fail to see how proper quantization noise modulation destroys much more data than resistor ladder non-idealities. Dynamic range on both well implemented technologies seem pretty close to me, even after going crazy with compensation on an R-2R implementation.

Saying that something is worse that something else cuz somebody else said so may fly on a casual conversation. It does not fly on a more professional and serious conversation (and believe me, that's an understatement). I wouldn't mind that much if I have not seen this parroted over and over again in several places even in the face of measurments not supporting this crazy data destruction brought forth by well implemented DS designs.

Why hell, aren't most reputed Audio Analyzers based on D-S DACs and ADCs?

I don't have a problem if someone likes this or that DAC more and it happens to have R-2R. But the claim of D-S lossyness and approximationness vs R-2R does need a bit of data to support it IMO.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: madaboutaudio on August 31, 2015, 02:38:17 AM
The linearity problems with R2R is due to resistor matching and thermal/electrical issues and not related to mathematical/algorithm approximation like Sigma Delta.

Here outlines the problem with Delta Modulation(Sigma Delta Modulation is a derivative/improvement of delta modulation, with additional feedback/comparator & oversampling to improve full scale/slope output):
(http://www.strymon.net/wp-content/uploads/deltaModSig_outlines.png)

I read somewhere R2R DAC/ADC only works well to a certain frequency(up to 3 Mhz or so) , anything above in MHz to GHz, then S-D/D-S DAC/ADC makes more sense.

Quote (selected)
This technique has found increasing use in modern electronic components such as converters, frequency synthesizers, switched-mode power supplies and motor controllers, primarily because of its cost efficiency and reduced circuit complexity.[1]

https://en.wikipedia.org/wiki/Delta-sigma_modulation

The issue with Sigma Delta(especially high order sigma delta) is it's using a complex form of feedback mechanism to maintain it's stability. Most Music Signals will stay within stable conditions, but some forms of music instrument(those with rapidly changing loudness/tones) can expose the weakness of Sigma Delta like French Horns and Obode.

You can achieve high dynamic range/SNR with high order Sigma delta that looks good on measurements(i.e. ES9018S). But does it sound good/right(tonally/timing) to audiophiles is another thing all together.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: ultrabike on August 31, 2015, 03:56:49 AM
The linearity problems with R2R is due to resistor matching and thermal/electrical issues and not related to mathematical/algorithm approximation like Sigma Delta.

They are not related, but they are both non-linear. That said, if I remember correctly, I can come up with a delta sigma noise transfer function that may mitigate the passband noise to a point where >  21-bits are possible save for perhaps other non-idealities in the conversion outside of "the math" path.

Here outlines the problem with Delta Modulation(Sigma Delta Modulation is a derivative/improvement of delta modulation, with additional feedback/comparator & oversampling to improve full scale/slope output):
(http://www.strymon.net/wp-content/uploads/deltaModSig_outlines.png)

The slope of the input signal is bounded by the bandwidth of the signal and the number of input bits, so the sky is not the limit. A proper implementation would take that into consideration. Furthermore, many TOTL delta sigmas are not 1-bit but multi-bit (in the feedback as well), which together with a sufficiently large set of accumulators, should result in no issues as described there.

I read somewhere R2R DAC/ADC only works well to a certain frequency(up to 3 Mhz or so) , anything above in MHz to GHz, then S-D/D-S DAC/ADC makes more sense.

This is incorrect. R-2R are used for applications that require faster conversion, but lower resolution such as Oscilloscopes. D-S works better with applications that require lower speed conversion but higher resolution.

As far as cost, I would argue that indeed it would be cheaper to make D-S designs if for the equivalent R-2R you have to cherry pick and if you need a ton of discretes to make it work very well.

https://en.wikipedia.org/wiki/Delta-sigma_modulation

The issue with Sigma Delta(especially high order sigma delta) is it's using a complex form of feedback mechanism to maintain it's stability. Most Music Signals will stay within stable conditions, but some forms of music instrument(those with rapidly changing loudness/tones) can expose the weakness of Sigma Delta like French Horns and Obode.

You can achieve high dynamic range/SNR with high order Sigma delta that looks good on measurements(i.e. ES9018S). But does it sound good/right(tonally/timing) to audiophiles is another thing all together.

You have evidence that a well regarded D-S IC will not stay within stable conditions with 24-bit audio signals?

Also, I'm more interested in a PCM4222 than an ES9018S. I like multi-bit DAC chips better. Seems to me it combines the best of both worlds.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on August 31, 2015, 04:19:27 AM
There's no real way of coming to a solid conclusion -- one way or another -- because companies / products / concepts like the following ...

http://audio-database.com/COUNTERPOINT/etc/da-10-e.html

(http://audio-database.com/COUNTERPOINT/etc/da-10(4).JPG)
...are few, far between or long forgotten (did someone mention the DA-10 in this thread, or Purrin's 'D-S sucks' thread at H-F?)
... much less the fact that not many DIYers (or manufs) have pursued D/A projects with swappable modules (some D-S, some R2R, some Bitstream**). (The 2-1994 Stereophile review for the DA-10 did have reviewer R. Harley strongly choosing AD1862 over CS54328: "The AD 1862 portrayed the transient attack of fingers on strings—virtually missing from the C54328—infusing the music with greater life and enthusiasm. The CS4328 tended to mute the attack, thus blurring the distinctions between notes. Moreover, the AD1862’s “bouncier” bass quality made music much more rhythmically involving than the C54328. Bass guitar had more weight, power, and “purr,” which, when combined with the deeper extension and wider dynamics, produced a greater awareness of the music’s rhythmic characteristics.")

** The 1-bit Sony DAC inside Optimus CD-3400 was noteworthy. And many decent-sounding Philips and Marantz CDPs (early 90s) used Philips TDA1547 (Bitstream DAC).
Title: Re: Vintage R2R/multibit DAC Thread
Post by: BassDigger on August 31, 2015, 04:25:08 AM
I got tired of this discussion on the other forum! I'll see if it's a bit less evasive (and effusive) here.

It basically seems to come down to trying to determine what this elusive difference is, between the two techs, that makes many discerning listeners prefer one technology, over another. Remember, these discerning listeners have picked out the technology of the conversion process, as the main factor. (Although I've never seen anyone discount the importance of implementation.) Why do they do this?

My incredibly simplistic understanding is that the DS process uses lots of approximations, and processes them very quickly, making it more susceptible to any inaccuracies (perhaps caused by the limitations and imprecisions in the hardware).
Whereas R2R uses a much simpler and real time process that is less susceptible to any imprecisions caused by the hardware.

And for the record, I'll go for sound over measurement, every time.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: ultrabike on August 31, 2015, 04:32:00 AM
Discussing which DAC sounds bestest is subjective in many ways. I have no problem at all if someone tells me that to him AD666 sounds punchier than PCM69.

It's a different story when we are talking about latest iterations of TOTL D-S IC where folks start to claim that it clips, can't keep up with the signal, it "approximates" stuff unlike R-2R and things like that.

I got tired of this discussion on the other forum! I'll see if it's a bit less evasive (and effusive) here.

It basically seems to come down to trying to determine what this elusive difference is, between the two techs, that makes many discerning listeners prefer one technology, over another. Remember, these discerning listeners have picked out the technology of the conversion process, as the main factor. (Although I've never seen anyone discount the importance of implementation.)

That's fine

Why do they do this?

My incredibly simplistic understanding is that the DS process uses lots of approximations, and processes them very quickly, making it more susceptible to any inaccuracies (perhaps caused by the limitations and imprecisions in the hardware).
Whereas R2R uses a much simpler and real time process that is less susceptible to any imprecisions caused by the hardware.

This IMO, is not fine. DS AFAIK no more approximates stuff than the R-2R does. It just easier to understand R-2R than DS because R-2R is equivalent to a bunch of binary additions. D-S is not.

Furthermore, DS process things at an oversampled rate because it requires bandwidth to move stuff out of the audio band. Which in turn makes it good for relatively slow conversions, but not great for applications that require Gbps conversions.

And for the record, I'll go for sound over measurement, every time.

That's fine.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: BassDigger on August 31, 2015, 04:39:58 AM
This IMO, is not fine. DS AFAIK no more approximates stuff than the R-2R does. It just easier to understand R-2R than DS because R-2R is equivalent to a bunch of binary additions. D-S is not.

Furthermore, DS process things at an oversampled rate because it requires bandwidth to move stuff out of the audio band. Which in turn makes it good for relatively slow conversions, but not great for applications that require Gbps conversions.


Is jitter potentially a bigger problem for DS?


Where does audio rate, as a far as speed is concerned?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: ultrabike on August 31, 2015, 04:55:46 AM

Is jitter potentially a bigger problem for DS?


Where does audio rate, as a far as speed is concerned?

Jitter? Not in particular. That I think is more of a clock issue which would be common ground for both designs. In fact, some high resolution Jitter Attenuators rely on simple delta sigma approaches.

Audio rate? I think both should be able to handle 192k fine.

It's a mater of finding out if there is a difference in performance and showing up with valid and real data. I may try to procure one of those QA400 thingys Merv has to look myself into it. But no money for that this year for me. Sorry about that :(

But even then. I think the QA400 thingy is DS based too. So I dunno.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: BassDigger on August 31, 2015, 05:07:25 AM
It's a mater of finding out if there is a difference in performance and showing up with valid and real data.

And there we have the crux of the issue; What data? What are you going to measure?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Anaxilus on August 31, 2015, 05:09:45 AM
Yes. What measurement indicates pretty much every sigma delta DAC to be grainier and rougher in treble than R2R DACs? Let's look there or find it first rather than beating around the bush.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: ultrabike on August 31, 2015, 05:18:52 AM
If it is the delta sigma accumulator running out of juice as previously described, I guess one could pulse a bunch high amplitude band limited but relatively high slope pulses and see what comes out.

You got some ideas Mike?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: madaboutaudio on August 31, 2015, 06:21:51 AM
On the topic of sigma delta stability, loop filter and noise shaping and etc, it's a very complex subject:

http://yadda.icm.edu.pl/yadda/element/bwmeta1.element.baztech-article-BUS8-0020-0008/c/httpaa_czasopisma_pan_plimagesdataaawydaniano1201108noisetransferfunctiondesignandoptimization.pdf

How are you going to determine which noise shaping works best? It's kind of a black art, like how ESS tuned their Sabre dacs.

http://www.teddigital.com/ES9008B_tech.htm
Title: Re: Vintage R2R/multibit DAC Thread
Post by: ultrabike on August 31, 2015, 07:22:58 AM
Most things are not simple and easy. It takes time to develop something. It takes time to figure details in almost anything.

Noise transfer function is not too bad IMO depending on background.

Last time I checked ESS, it seemed to me that one of the things they do is detect silence and shut down stuff. An alternative approach would be to use a 1.5-bit (1, 0, -1) output/feedback, which is multi-bit at a basic level. I'm not a big fan of what I've read about the ESS. In fact, I think even the ODAC moved away from ESS for this and that issue.

If you have proofs about the PCM4222 or AKM1234 being pieces of shit, that go unstable and explode then by all means provide them. I honestly don't have proof because the tools I have such as my POS 2i2 will proly not sort things out.

This is not a contest. I don't have a personal/commercial interest whether one device is better than the other. If one device is better than the other, then that's that.

Title: Re: Vintage R2R/multibit DAC Thread
Post by: madaboutaudio on August 31, 2015, 07:53:01 AM
Disclaimer: I own both the Audio-gd master 7 and Schiit Yggdrasil, both are R2R DACs.

I haven't heard any PCM4222 or AKM1234 before. So I can't make any comments on them.

The hybrid sigma-delta/R2R Ti PCM179x is only mid-fi grade at best. Can be dull/laid back sounding. It's predecessor, Burr Brown/Ti PCM1704UK is so much better in all aspect.

Certainly there are are good sigma delta dacs out there. AD1955(Bricasti M1) or AKM4399(Gungnir) or Matrix X-sabre(ES9018S) or Geekout V2(ES9018AQ2M/K2M) or the NAD M51(propriety sigma delta).

However these dacs are certainly not nearing Yggdrasil or MSB Analog kind of performance.

Go listen to one of the good R2R dacs for yourself. Measurements and Specifications are only part of the story, the key performance benchmark of an audiophile grade dac is level of sensory enjoyment you get out of it(subjective).

Title: Re: Vintage R2R/multibit DAC Thread
Post by: ultrabike on August 31, 2015, 08:16:55 AM
I'm not making any claims as to which one sounds better. And I understand that Measurements and Specs mean little if the end product is not liked.

I think I heard the Yggdgrasil a few times, but not necessarily critically. I liked what I heard. Not only that. Measurements back this up indeed.

Just saying that if we are going to say that D-S is a piss poor approximation and that's why the technology sucks in general, then it would be desirable to back that up with something other than Mike and a bunch of folks told me so. Preferably with a decent D-S implementation. I mean, I think the QA400 uses CS4272 and from what I remember I don't think it blew up when Merv did a loopback on it.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on August 31, 2015, 09:34:37 AM
Certainly there are are good sigma delta dacs out there. AD1955(Bricasti M1) or AKM4399(Gungnir) or Matrix X-sabre(ES9018S) or Geekout V2(ES9018AQ2M/K2M) or the NAD M51(propriety sigma delta).

However these dacs are certainly not nearing Yggdrasil or MSB Analog kind of performance.
But Yggdrasil is a PREMIUM dac with lotsa stuff (improvements) OTHER THAN THE DAC CHIP.
That was the whole point of the Counterpoint DA-10 ref. I made earlier in the thread.
You've gotta level the playing field. (The ancient Counterpoint D/A does that to a very large, scientific extent, using its proprietary module)
That said, a trained listener can distinguish acoustic differences among electronic architectures and schemas: e.g., non-oversampling vs. oversampling. But I think the value-judgement calls between D-S vs multi are much trickier. I've gotta a closet full of vintage multibit (including some high end stuff) ... yeah it sounds good/different ... but not important enough to drag outta retirement. My daily work-and-play D-S system -- Asus Xonar ST-based -- is aged and clunky, but no way I'll trade in the convenience of multi-TB HDs and playlists with months full-o-FLACs.
Quote (selected)
Go listen to one of the good R2R dacs for yourself. Measurements and Specifications are only part of the story, the key performance benchmark of an audiophile grade dac is level of sensory enjoyment you get out of it(subjective).
"Measurements and Specifications [as known to human science mid-2015] are only part of the story". Science and metrics will improve, and parameters will be added to the growing list of tracked specs. In the end, it may not matter ... if you sample enough in the A/D process, you don't need fancy D/A. That's essentially the principle behind DSD; Google "The Best DAC is no DAC".
Title: Re: Vintage R2R/multibit DAC Thread
Post by: ultrabike on August 31, 2015, 02:31:14 PM
The recent discussion is not about what is more convenient since we are looking at performance parameters.

It is not either about how DSD removed the need of a fancy D/A. IMO it didn't. The Sony/Philips DSD format seems problematic and perhaps more concerned with making money than improving performance.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Priidik on August 31, 2015, 03:01:14 PM
Anyone has an opinion on AD1862 based units?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: jai1611 on August 31, 2015, 04:02:06 PM
Anyone has an opinion on AD1862 based units?


Heard a heavily modded Audio Alchemy with a tube IV/output stage. Sounded quite mellow - decent resolution, quite relaxed sounding, maybe missing some PRAT. The guy who built it had tried the Tentlabs PCM63 based DAC with the same tube stage and preferred the AD. His feedback was that the PCM63 was more dynamic and big sounding but didn't have the same warmth, which he likes. He let the Tentlabs go and kept the Audio Alchemy
Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on August 31, 2015, 05:39:50 PM
Anyone has an opinion on AD1862 based units?
They were one of the module DACs for the aforementioned Counterpoint DA-10 (see the audio-database link in that post).
The 1862 are possibly the most sought-after DAC on DIY forums like DIYHiFi*, many claim even superior to TDA1541A (double crown)**. The were rare and $$ (on ebay) for years. Recently, the Chinese seem to have acquired a huge stash of vintage R2R dac ICs, and at pretty reasonable prices.
diyinhk.com has AD1862 kits for $99USD "The sound from this DAC is unique, sweet, clear and full of detail that the newest cutting edge delta sigma DAC can never produce." [alas, Non-oversampling!!]
(http://www.diyinhk.com/shop/329-large_default/ad1862-r2r-isolated-nonoversampling-nos-audio-dac-with-fifo-reclock.jpg)
I already noted the Philips TDA1545A and similar TDA1387 earlier in this thread. Dirt chip for raw chips.
Not sure how/where the Chinese acquired these vintage parts. But from some of the conversations on the DIY forums, the inventory (authentic or not; high-grade or not ) is quite sizable.

* Often, a PMD100 + 2x AD1862 set is modded into Philips/Marantz CDPs like the CD-80 (replacing their stock SAA7220+TDA1541A).
** The most $$ D/A Stereophile ever reviewed was the Zanden DAC [Nov. 2006; $15,470 ],  a non-oversampling D/A that uses vintage Philips TDA1541A "double crown,".
Title: Re: Vintage R2R/multibit DAC Thread
Post by: bixby on August 31, 2015, 06:17:58 PM
I wish I still had my EAD 7000 MK III (r2r) still around to compare.  From memory pretty darn grainy in the treble to me compared to some of the D-S replacements, but they had their problems as well.  Stuff just keeps getting better at really good prices all the way around.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: BassDigger on September 01, 2015, 07:52:26 AM
It's nice to see that this thread is coming back on topic. (Not that I played any part in the OT  :)p8  )

One point that I'd like to reiterate is that when we're talking about vintage dacs. Unless we find one that's already been modded, that's what it's gonna need: modification.

A vintage dac is a safer bet than a vintage player; there's no transport mech to die on you. But, at the very least there will be some components (mostly capacitors) that will be beyond their useful working life. Anyone who's handy with de-soldering and re-soldering could replace, and maybe upgrade these. You'll then have a dac that's at least as good as new and give you some serious performance per pound.

But the other issue is the implementation. I think that most of us here believe that a R2R chip is the root to the best sound. We buy a vintage dac to get this sound in a cost effective manner. But the issue is that most of these dacs were made in a time when digital was less well understood; some popular and famous dacs had some serious design flaws, predominantly because of then unknown phenomenon. NOS/OS is the most well known (and disputed) of these. But there are other examples that are (today) undisputedly recognised as fundamental design flaws, that are usually manufacturer specific. In many cases these flaws are easily rectified, taking the dac on to another level.

Of course, if you're buying ready modified, you're gonna have to make sure that you're not buying somebody else's failed experiment. So you should buy from someone who knows what they're doing. Or get your vintage dac first, and find someone reputable to mod it for you, unless you can do it yourself.

So, sourcing a good vintage R2R dac (for a good price) is just the first part. But with the right mods it can become a real bargain.
It makes me shudder to think of how many great dacs have ended up in the trash, just because someone thought th
at it was too old!
facepalm
Title: Re: Vintage R2R/multibit DAC Thread
Post by: MuZo2 on September 06, 2015, 07:27:09 PM
Tomorrow I will receive r2r . Four Burr-Brown PCM 63P-K 20 bit,push-pull for each channel.Lets see how it goes.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: frenchbat on September 06, 2015, 07:37:50 PM
Tomorrow I will receive r2r . Four Burr-Brown PCM 63P-K 20 bit,push-pull for each channel.Lets see how it goes.
brand/model ?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: MuZo2 on September 07, 2015, 07:06:36 AM
Parasound hd 1600
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Sorrodje on September 07, 2015, 07:31:03 AM
Parasound hd 1600

The one that was for Sale in North Europ (I don't remember where precisely) ? 


THis one ? http://www.finn.no/finn/torget/annonse?finnkode=61874898&searchclickthrough=true
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Priidik on September 07, 2015, 07:53:48 AM
Heard a heavily modded Audio Alchemy with a tube IV/output stage.

Thanks for your thoughts.

diyinhk.com has AD1862 kits for $99USD

This is what I had in mind. I want a throw-around dac for gaming :)
Title: Re: Vintage R2R/multibit DAC Thread
Post by: MuZo2 on September 07, 2015, 08:07:30 AM
The one that was for Sale in North Europ (I don't remember where precisely) ? 


THis one ? http://www.finn.no/finn/torget/annonse?finnkode=61874898&searchclickthrough=true

No was a local one in Germany. I contacted the other but shipping cost was lot. I guess its still available.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: paras1te on September 13, 2015, 08:59:31 AM

This is what I had in mind. I want a throw-around dac for gaming :)

Are you serious or kidding?
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Thad E Ginathom on September 13, 2015, 09:12:08 AM
I want a throw-around dac for gaming

HiFiMeDiY (http://hifimediy.com/DACs/ready-made-dacs)? Buy a couple of their cheaper ones. it won't hurt your wallet too much if you stamp on one while you are throwing it around.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Priidik on September 13, 2015, 05:58:53 PM
Are you serious or kidding?
I'm serious. Gaming also benefits from good chain. Though Yggy etc level is obvious waste on gaming.

HiFiMeDiY (http://hifimediy.com/DACs/ready-made-dacs)? Buy a couple of their cheaper ones. it won't hurt your wallet too much if you stamp on one while you are throwing it around.
I'd rather build something, or give up and buy a Go V2.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Thad E Ginathom on September 13, 2015, 06:08:57 PM
I'd rather build something, or give up and buy a Go V2.

Yes, a different class: but upsetting if you jump on it.

BTW... have you heard HFMD's little dongle's?  My first encounter was a modded one at a music-listeners' meet: It stood up well to stuff ten times the price.  I have one (unmodded*), and I occasionally bother to connect it between my tablet and 'phones when travelling, but mostly not.

*except for replacing a broken-wire USB tail
Title: Re: Vintage R2R/multibit DAC Thread
Post by: kothganesh on September 14, 2015, 10:30:49 AM
....................
I'd rather build something, or give up and buy a Go V2.

The GO V2 should be very seriously considered. Get yourself a TRRS connector and you are in business.
Title: Re: Vintage R2R/multibit DAC Thread
Post by: Priidik on September 14, 2015, 01:26:57 PM
I like to DIY stuff for various reasons, like a extra hobby or smth.
Anyways DIY is not necessary these days to not get ripped off, it seems.
If all Changstar smarts are true (haven't tried one myself), then it's improbable I could build something better than GO V2 for its money's worth.
@ Thad: The local pirate favor biases more towards GO V2, so I must follow the crowd  p:3