CHANGSTAR: Audiophile Headphone Reviews and Early 90s Style BBS

Lobby => Amp and DAC Measurements => Topic started by: Hands on October 28, 2014, 08:47:44 PM

Title: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Hands on October 28, 2014, 08:47:44 PM
A Few Notes

Before I give you my somewhat “finalized” subjective thoughts on the Classé Audio DAC-1, I just want to reiterate for anyone that might not realize that I generally like a smooth, laid-back sound with my audio gear. I seem to fatigue quickly and easily for often unexplainable reasons (could be young age, general hearing sensitivity and tastes, tendency to listen to harsh music and too loudly, gear I have on hand, chronic headaches from sinus congestion and allergies, etc.). Hence why I gravitated to NOS DACs for a while. The Metrums in particular got me involved in the music without setting me on edge, which most sigma-delta or even just most oversampling DACs apparently seem to do.

Also take note that I’m sharing these thoughts after using the DAC-1 with the JKSPDIF Mk3. This converter comes with a 15dB attenuator, which, in theory, reduces signal reflections. I never noticed a huge difference with it either way on other DACs, but it is almost required on the DAC-1 due to how much of a difference it made with the sound. Thus, anything I say could change noticeably if I were to try different gear in my equipment chain. I also only really had the Audio-GD NOS1704 and Yulong DA8 on hand for direct DAC comparisons, and any other thoughts are based purely on potentially faulty memory. Hopefully these notes will help you frame my subjective impressions and point of view when speaking about the Classé Audio DAC-1.

Subjective Listening Impressions and Other Thoughts

There has to be something special about these older DACs and the chips or modules they used back then. It took very little time at all to recognize I was hearing something that just sounded different than what I was used to. My immediate thoughts beyond this were “BIG, 3D sound” and “very detailed across the spectrum.”

Holy crap, does this DAC have kick to it! And it’s clean and quick sounding, too. For example, if you’re a metal fan, this does wonders for double bass kick drumming. Both the NOS1704 and Yulong DA8 sound soft in comparison. More of a rounded “thud” in comparison. The DAC-1 is very dynamic and has lots of punch. It isn’t quite as quick with internal micro-dynamics and shifts as the NOS DACs I’ve heard, but it doesn’t leave me wanting here. As a whole, it is more dynamic. Pretty good sense of blackness as well.

Some folks have said the DAC-1 can be a bit on the cool side of things. That’s hard for me to agree or disagree with. On one hand, it doesn’t have the bass and mid bloom I hear on some other DACs, like the NOS1704 and DA8. Perhaps the DAC-1 could use a bit more warmth for my tastes. I’d probably prefer that. On the other hand, the DAC-1 has a very full-bodied yet clean tone. Nothing really sounds thin or lacking. I think it’s just that it’s quick, clean, and detailed. It’s like the full-bodied tone of a NOS DAC but without the additional warmth and slight mushiness, if that makes sense. It has a good sense of pitch across the board, even in the bass. I suppose you could call it lean but muscly or buff and well defined in the sense it doesn’t have a false sense of warmth but sounds big in size, power, and tone, is impactful, and is detailed/defined in most or all regards.

The DAC-1 also doesn’t seem to have the same sort of grain as something like the DA8. I don’t think it’s quite as smooth and syrupy sounding as the NOS1704, which is probably expected, but detail does seem to flow fairly effortlessly on the DAC-1. It doesn’t bring background details to the forefront in the same way the DA8 does, yet still manages to sound more detailed overall. The DAC-1 seems to be one of the more resolving DACs I’ve tried, and it breezes through complex passages without seeming troubled at all. And even subtle cues aren’t hidden or smoothed. Lots of life and breath to the music. Seems to pull out every little detail, but not necessarily in an exaggerated way.

If anything, for my tastes, the DAC-1 might almost be too detailed. Too precise. Lingering cymbal crashes, for example, have a sort of sparkle, crunch, and/or decay and reverberation to them that makes them sound lifelike and full-bodied, but presented in such a way I’m not really used to from other DACs. And the airy, 3D, almost holographic soundstage makes everything easy to pinpoint and cuts through all the crap (this goes back to the “BIG, 3D sound” comment from earlier).

Yet, I think it’s this ability to dig deep and present seemingly every detail that almost starts to give me information overload, which can to listening fatigue. It’s almost like things become too textured and detailed for my ears to keep up with. However, I still can’t explain exactly what it is that starts to wear on me over time. It’s not like when doing side-by-side comparisons that anything stands out as wrong on the DAC-1. Quite the opposite, it’s more like a breath of fresh air when I switch to it. And a lot of times, the treble presentation seems a bit more laid-back or less in your face than other DACs in back-to-back comparison. More natural. Occasionally not, but usually. Again, very hard to explain. It’s not the sort of fatigue I got from the X-Sabre or other DACs that were either too sharp sounding, too lean, too grainy, etc. Maybe the DAC-1 is just a touch forward with upper-mids and treble. Maybe it’s a bit too powerful or lively sounding for my tastes (i.e. not relaxed or laid-back across the entire spectrum). Maybe I’m hearing some digital hash in some areas, like the cymbals. Very hard for me to say. Perhaps it really is just information overload on my end, as that’s something I experience pretty commonly even outside of audio. I suspect this is just my ears, tastes, and sensitivities being odd, and not something others would notice so much. I’m also still investigating changes to my equipment chain that might suit my needs better. I might just need to pair it with a bunch of laid-back gear. ;) I think these more “negative” thoughts are more a commentary on my tastes and sensitivities, as I’ve said a few times already, so take it as you will. This is coming from the guy that seems to prefer something like the Metrum sound, after all.

Anyway, one other thing I’ve noticed about the DAC-1 is that it seems to be fairly transparent in most regards. It seems to highlight the strengths and weaknesses in my gear more so than any other DAC I’ve tried. It’s more or less the opposite of a NOS DAC in this regard, which seems to just make everything easier to listen to, IMO. This is both a blessing and a curse. Things that sounded good before sound really good now, and things that were on the edge before start to become more annoying to me. Things that sounded bad before sound worse now, but probably in a more accurate way. Differentiating between amps and other gear changes is easier than before. The DAC-1 also doesn’t seem to sugar coat harsh or poorly recorded material. I suppose you could call it very revealing, or perhaps not very forgiving, but not in that sort of sterile or overly analytical way you’d expect. This is why I’m still investigating other gear, even cables, for the DAC-1 to see if I can’t get it sounding more relaxed and more to my tastes.

In a way, I want to describe the DAC-1 as sort of a best of both worlds. It seems to have the sort of precision you get from the PWD or X-Sabre without sacrificing tone, emotion, and musicality. It also just sounds more “real” than the sigma-delta DACs I’ve heard before. While it remains to be seen if I’ll keep it in the end, as I may just settle with the potential need for something very smooth and relaxing (don’t be surprised if this goes up for sale in the next couple months), I do feel like this is one of the best DACs I’ve heard yet despite having silly sensitive weirdo baby ears and tastes. Maybe I am just not worthy of the awesomeness within the Classé Audio DAC-1. I’m very curious how it would sound with different digital filtering methods, as I’m stuck with the 8x OS implementation for now. Not enough skillz to try modding it for something else like I know some have tried on other DACs. Maybe the upcoming Yggdrasil will be what I’m looking for, as what they’ve said about the filter and time + frequency domain optimization sounds promising. We’ll see.

Upcoming

Measurements coming up next. Same procedure as my most recent DAC measurements, so I’ll spare you those repetitive details for once. Spoiler alert: It measures well for being two decades old and makes you wonder about how far DACs haven’t come since then. I also took some pics of the DAC-1’s internals to share.
Title: Classé Audio DAC-1 RightMark Measurements
Post by: Hands on October 28, 2014, 09:23:09 PM
Given the DAC-1 is limited to no greater than 16/48, that's all I could take for measurements. Surely the DAC-1 won't measure competitively these days with all of the DAC progress that has been made in two decades...right?

A few notes on measurements: Frequency response treble extension seems to have less droop or more extension vs. most other DACs I've tested, save for the PWD Mk1. Noise floor is roughly 3dB higher than, say, the X-Sabre, but still very clean. This could also be due to me living in a different, older house now. It's not a 100% identical measurment environment. Distortion looks great, though I've measured DACs with slightly lower 2nd order HD. Nothing to worry about. Not sure how much the slightly higher noise floor covers up other distortion characteristics, but it looks very clean. The distortion characteristics and distribution above the 24KHz point look interesting (sorta reminds me of some stuff I saw on the Metrums), but if it means anything, I'm not sure. Overall, a DAC with these measurements, minus the 16/48 limitation, could still sell for big bucks these days.

For anyone that cares about how RMAA scores and reports this stuff numerically:

Frequency response (from 40 Hz to 15 kHz), dB   +0.01, -0.06Excellent
Noise level, dB (A)   -94.9Very Good
Dynamic range, dB (A)   94.8Very Good
THD, %   0.0036Very Good
THD + Noise, dB (A)   -84.5Good
IMD + Noise, %   0.0085Very Good
Stereo crosstalk, dB   -94.6Excellent
IMD at 10 kHz, %   0.0014Very Good
General performance    Very Good

Frequency Response:
(http://i.imgur.com/jGUxlS7.png)

Noise:
(http://i.imgur.com/j9jxFCv.png)

Dynamic Range:
(http://i.imgur.com/rq8xfIH.png)

THD:
(http://i.imgur.com/xyILMLK.png)

IMD:
(http://i.imgur.com/cN56OvV.png)

Stereo Crosstalk:
(http://i.imgur.com/S2Fcs5e.png)

IMD (Swept):
(http://i.imgur.com/5j6IQ7g.png)
Title: Classé Audio DAC-1 Various ARTA Measurements
Post by: Hands on October 28, 2014, 09:36:43 PM
1KHz square wave measurement is about what you'd expect from 8x oversampling, some sort of linear-phase with sharp roll-off I'm guessing (it uses the PMD100, IIRC, and also verified my oscilloscope shows the same looking square wave):

(http://i.imgur.com/2ciQETK.png)

1KHz sine wave at -90.31dB. DAC-1 does show the quantization steps, though not as cleanly and perhaps without quite as much amplitude (perhaps because not outputting 2V?) as I've seen from other DACs. Still a pretty good result:

(http://i.imgur.com/dZ1d30E.png)

Jitter results look pretty good from the JKSPDIF Mk3 w/ 15dB attenuator. Spuriae are all quite low, about as good as you can expect from 16-bit, IIRC. No skirting around the signal, and very clean looking overall. And this DAC is two decades old.

(http://i.imgur.com/n0ZN2YN.png)

13KHz and 14KHz, at 0db (left) and -3dB (right):

(http://i.imgur.com/UfjWmjT.png)

19KHz at 0dB (left) and -3dB (right):

(http://i.imgur.com/2g1iR43.png)
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: spoony on October 28, 2014, 09:50:36 PM
Cool!, $$$?
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Hands on October 28, 2014, 09:58:56 PM
I'll copy/past something Marv said in the Theta Gen V thread that pertains to this DAC and the question above:

Quote (selected)
Anyways, Stereophile 1999 Recommended Digital Processors. This was before they sold out into Stereophool and added an A+ and A class with a Benchmark DAC1 (yeah the "Benchmark" for limp-dick sigma-delta DAC sound with no plankton but gross detail) in class A:
-Camelot Technology uther v2.0: $2999
-Classe DAC-1: $3995
-dCS Elgar: $12000
-dCS 972 digital to digital converter: $6995
-Mark Levinson No.30.5: $15950
-Meridian 518: $1950
-Muse Model 296: $3000
-Spectral SDR-2000 Professional: $8895 $$$
-Theta DS Pro Generation V-A: $3795
-Wadia 27ix: $8950 $$$

I picked mine up recently on eBay for ~$1.1K, though I'm not sure what they normally go for. I've seen some mention as low as ~$850, and I saw a previous listing for around $1.2K, so in the $1K ballpark range. I can easily see why it made Stereophile's list back then.
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Hands on October 29, 2014, 12:12:48 AM
Super clean inside:

(http://i.imgur.com/9RHP9tFl.jpg) (http://imgur.com/9RHP9tF)

To emphasize how big this thing is, I put my Leckerton UHA-6SMk2 inside it.

(http://i.imgur.com/AbeEsHul.jpg) (http://imgur.com/AbeEsHu)
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Marvey on October 29, 2014, 03:24:08 AM
great work!
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: firev1 on October 29, 2014, 03:40:23 AM
SPDIF input rejection is simply fabulous. For those wondering how does 16 bit look like at -90dbFS, compare this and the above measurement.

(http://i.imgur.com/1png06J.png)
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: kothganesh on October 29, 2014, 07:25:57 AM
I'm beginning to understand Marv's rant on HF today about modern versus vintage DACs.
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Hands on October 29, 2014, 08:28:57 AM
Yes, these vintage DACs are no joke. I'm thinking about it more and more and might try to pursue a NOS DAC based on something like the AD1862, 1865, TDA1541A, PCM6x/5x or similar...I'd be curious to see if someone could rig this UltraAnalog module up in NOS mode. Seems most of those chips I mentioned have fairly good specs, not to far off from the 1704 (which had much better measurable characteristics vs. whatever chips Metrum uses), but subjective reports from various individuals and sources make me think they'll sound better than the 1704. I could see that working out really well for my tastes. So, don't be surprised if the DAC-1 goes up for sale, as I think I'm just a NOS guy (sorry to disappoint some folks) but want to keep the goodness these vintage chips seem like they might bring to the table.
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Mr.Sneis on November 04, 2014, 06:08:33 PM
Hey Hans,

I am a complete dick for not having read this earlier I am sorry.

This month I jumped into a SFD-2mkii and I feel a lot of the same way about your comments here.  Namely for me I hear it is a little up-front (not Gungnir level) and maybe even borderline fatiguing.

I am coming from a Parasound d/ac 2000 and I feel like a loner saying this but it has many of the qualities you seem to prefer.  Laid back, check.  Good with crappy and good recordings check.  Non fatiguing check.  My only complaint really is the Parasound does not have the most expansive holographic sound stage ever but it does good enough that I feel the DAC does not draw attention to its flaws.

Again I wish I read this sooner as I just closed on the auction for my Para.  Would have been decent of me to have sent it your way for impressions/measurements but I think that ship has sailed now and it's all my fault!

The bottom line is this however, if you are a "design" purist I believe the Para has opamps in the output stage, it also does not have the beefiest power supply section I have ever seen.  You would think the SFD-2 weighing twice as much would be largely the same but better but trust me it is not -- case of implementation>>dac chip at play here.

(Pic by mastercontrolmedia via Flickr)
(https://farm9.staticflickr.com/8331/8133471109_46d1cbc42b_s.jpg) (https://flic.kr/p/doJaAv)
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Marvey on November 04, 2014, 07:53:58 PM
Quote from: Mr.Sneis on November 04, 2014, 06:08:33 PM
This month I jumped into a SFD-2mkii and I feel a lot of the same way about your comments here.  Namely for me I hear it is a little up-front (not Gungnir level) and maybe even borderline fatiguing.

Was the the one from Pcx or did you get it elsewhere? Some 6922s can sound like that. What tubes you got in it? Maybe try Amperex?
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Mr.Sneis on November 04, 2014, 08:20:12 PM
Heya Marv - it's from pcx.  I have some Amperex Orange Globe 6dj8's (Great Britain) leftover that I found bright in an old Melos Sha-1.  I may get around to swapping them out eventually but the tubes in the SFD-2 are Reflektor 6h23n-eb which seem to be well regarded.  Would be nice to hear your progress with the SFD-1 when you get it back.  I'll post more in the SFD-1 thread to stay relevant.
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Hands on November 05, 2014, 12:40:07 AM
Quote from: Mr.Sneis on November 04, 2014, 06:08:33 PM
I am a complete dick for not having read this earlier I am sorry.

This month I jumped into a SFD-2mkii and I feel a lot of the same way about your comments here.  Namely for me I hear it is a little up-front (not Gungnir level) and maybe even borderline fatiguing.

I am coming from a Parasound d/ac 2000 and I feel like a loner saying this but it has many of the qualities you seem to prefer.  Laid back, check.  Good with crappy and good recordings check.  Non fatiguing check.  My only complaint really is the Parasound does not have the most expansive holographic sound stage ever but it does good enough that I feel the DAC does not draw attention to its flaws.

Again I wish I read this sooner as I just closed on the auction for my Para.  Would have been decent of me to have sent it your way for impressions/measurements but I think that ship has sailed now and it's all my fault!

Bahaha, yeah, such a dick.  :))  All good on the Parasound DAC, but it would have been interesting to hear for sure. Oh well! The more I think about it, I'll probably just end up going NOS route in the end (meh, it works for my ears). I'm looking at some NOS DACs that use older chips, like the MHDT Lab DACs or something based on AD18xx/PCM6x or 5x, TDA154x, etc. I liked the NOS1704 for being more resolving than the Metrums, noticeably so, and I've heard great things about these chips subjetively relative to even the PCM1704. I can believe it. Datasheets on some look good for what they are. Lots of research to do.

Though I do wonder if a more laid-back amp (thinking Black Diamond or some tube amp) or even adding a tube buffer might help. Still interested in hearing Marv's SFD-1 as well.
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Marvey on November 05, 2014, 12:52:19 AM
I'm kind of interested in the Stockholm. Hans, maybe you can contact MDHT them on our behalf to get a loaner unit? PCM56 (precursor to 63) which means probably pretty darn good. NOS. Checks lot of boxes. You can probably tube roll to find the one that works for you best.
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Hands on November 05, 2014, 01:40:28 AM
Oh yeah, I've been eyeballing the Stockholm V2 for a while now. Not only can you swap tubes, I also read you can swap the PCM56 for AD1865 to change up the flavor, which sounds pretty cool to me. Price and subjective impressions seem right. If I can get someone lined up to take the Classe DAC-1 off my hands (want to compare to SFD-1 directly if possible, though), I think the Stockholm is next on my list. Though they do have the Atlantis DAC on the way, from what I gathered. AD1862-based. Either way, if not a loaner unit from MHDT, I'd be willing to tour anything I may get from them for myself.

Was also checking out the Audial Model S DAC (TDA1541-based) and Mojo Audio Mystique DAC (AD1865-based). The latter interests me for reasons I can't explain (maybe the simplicity?), but $2K+ for either of those is too risky for me to try or there's basically zero info and impressions on them. Not a whole lot of old-school chip-based NOS DACs floating around to choose from unless you want to go TDA1543.
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Hands on November 17, 2014, 12:12:02 AM
Some update thoughts on how a different USB->SPDIF or otherwise converter might change the DAC-1's sound: http://www.changstar.com/index.php?topic=1929.msg52176#msg52176

DAC still keeps its main characteristics, of course, but perhaps may be enough to sway one's opinion on the DAC. I haven't decided yet.
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Enigmatic on November 22, 2014, 04:32:36 PM
Hey guys, just FYI - MHDT was kind enough to send me a loaner for the Stockholm V2.
I will not be back in my country until early December though, the loaner is expected to arrive by next week. Have not gotten a tracking number from them just yet.

Will give some impressions, and update my rig listing here on Changstar (I guess that helps us all to better understand from which perspective one listens from).
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Marvey on November 22, 2014, 05:18:36 PM
Very nice. Can you ask them if maybe you can pass it on to a few others who are fans of R2R and tubes?
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Enigmatic on November 22, 2014, 06:00:05 PM
Quote from: marvey on November 22, 2014, 05:18:36 PM
Very nice. Can you ask them if maybe you can pass it on to a few others who are fans of R2R and tubes?


No probs, I can ask them, marvey.

One caveat though - I think the Stockholm V2 does not switch between 110v and 230v automatically (I'm from Asia actually, so the unit I'd be receiving will be a 230v version).

Anyone from a region with the same voltage?


Actually I've approached them with the intention to buy, but they kindly offered me a loaner so I could decide if it works with my setup. Nice chaps really. If it sounds good and all that, I will grab a piece - I had very good experience with Taiwan made products (MHDT is based in Taiwan), i.e. my speakers are single driver Tang Bang based made-in-Taiwan, and I love how they sound.
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Hands on November 22, 2014, 06:28:23 PM
I believe you can adjust the voltage internally with jumpers. If you send it to some folks in the US, I'd absolutely love to try it out!
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: Enigmatic on November 22, 2014, 06:42:18 PM
Quote from: hans030390 on November 22, 2014, 06:28:23 PM
I believe you can adjust the voltage internally with jumpers. If you send it to some folks in the US, I'd absolutely love to try it out!

Oh.. Crap. Sorry. I genuinely did not realise that.
You're right, Hans, on their site: http://dhost.info/mhdtlab/vsetting.htm

I'll have a run at it first - If it's good I will just buy it then set up a loaner's thread here on Changstar.
Otherwise, I will drop them an email for their permissions and blessings (lol - From where I am this is part of our lives) to send it off to another person.


If I do wind up buying the Stockholm V2, I should be expected for another business trip early next year, so I shouldn't miss the Stockholm V2 too much during that period.  :)p7


On a side note, I will just drop them an email and hook them up with marvey, so none of you need to wait for me. :)
Title: Re: Classé Audio DAC-1 Measurements and Subjective Impressions (Mid-90s UltraAnalog)
Post by: firev1 on November 22, 2014, 07:12:34 PM
Holla Enigmatic, in Asia as well, SG to be exact.