Topic: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit. (Read 37270 times)

victor25 · « **Reply #70 on:** March 23, 2013, 07:46:10 PM »

Wow, that looks amazing! Why not 'make it perfect'. I know perfect is impossible, but why not try to get as close as you can?

Marvey · « **Reply #71 on:** March 23, 2013, 07:49:06 PM »

Because one adds more and more PEQ filters without any discernible improvement in sound just to get a good looking line. I think I already have 5-6 PEQ filters on the mains, and even that is slightly overboard. Honestly, I could get away with just 2 or 3 PEQ filters and be happy. I'll post the EQ.

Marvey · « **Reply #72 on:** March 23, 2013, 08:01:56 PM »

EQ settings on the mains and supertweeters. These were the settings on the mains when LFF and Anax last heard the system. It's actually slightly brighter than I would prefer it; it is however more accurate. I would have preferred it maybe .075db lower in the lower treble. (Fractions of a db, especially if the EQ band is wide, make a huge difference - hopefully this gives people insight of where I am coming from when I shit on headphones with nasty ringing or simply horrible FR characteristics.

Marvey · « **Reply #73 on:** March 23, 2013, 08:25:38 PM »

Why?

So anyways, why did I want to do this? I heard a back-loaded wide-band horn speaker, the Voxactiv, at THE SHOW, and very much liked certain aspects of it: the immediacy, the purity of tone, the dynamics.

It sort of got me thinking because I had built many multi-way speaker systems, with PXO and AXOs (half of my parents' garage is dedicated to old speaker cabinets.) The AXO systems I built were super precise, detailed, clean, and powerful sounding, but because the AXOs were of crappy quality (cheap Digital XOs, cheap op-amps, etc.), they always sounded rather flat and clinical. As for the PXO systems (and I did not want to spend a fortune on $$$ inductors, caps, etc.), well, I felt that the PXO components always sort of sucked the life and dynamics out of the music. I had also built high-efficiency horn systems based on JBL compression drivers. Those were clean, loud, dynamic, but there was always the horn coloration, and it always seemed if the horns were more meant to beam energy through a crowd, like an alien-death-ray, despite any attempts at EQ.

Anyways, I think the headphone experience rather ruined me because it made me truly understand and appreciate how transducers without PXOs of any sort were really special in their clarity and immediacy - despite the fact that Grados have probably caused me some hearing damage. I started to get accustomed to very simple signal paths - with great DACs with great amps (no pre-amp in the way either.) I think the moment that really made me realize the shortcomings of PXOs was when I started to use the UERM. Great accurate FR, but I always felt the UERM to have a slight PXO veil and suckage-of-life, especially when not powered by an amp, compared to other IEMs with simpler 2-way or no crossover. Then I heard the active PP6, and realized that AXOs have short-comings in another way. The PP6 really reminded me of my prior AXO systems: super precise, detailed, clean, and powerful sounding, but... soulless.

So going back to the Voxactiv's, their big problem was a rising frequency response which pretty much made LFF ask: WTF guys? How can you stand that shit?

Marvey · « **Reply #74 on:** March 23, 2013, 08:44:17 PM »

How can you stand that shit?

So that's what got me really thinking. It many ways, the old-fart rich audiophiles are very primitive in thinking. They like doing things the hard way. Like finding some exotic tube, preferably from some fortress in Poland or central Europe, which only manufactures said tubes in the spring and fall (summer being too hot - no A/C; and winter being too cold - all energy must be used for sustenance), which has special properties in ameliorating the rising treble response.

To me, it's 2013. Computers can perform complex PEQ without even breaking a sweat. Packages like JRiver MC come with some great DSP tools, and if we don't like them, we can simply obtain other VST plug-ins. Now, there's the old-fart rich audiophile argument that EQ fucks things up, and I agree to some extent, but only when the EQ is extreme. However such an argument is bullshit anyways. A recording is usually EQ'd from the mic. The board could have global EQ. The mixing process involves EQ. The mastering process involves EQ. Your recording has already been EQ'd at least three or four times over. Any EQ with a delicate touch is not going to be a case of the cure being worse than the disease as so many old-fart rich audiophiles would like to believe. I'm sure there's a reason why HiFi equipment doesn't come with tone controls anymore: that $5K amp is too bright, the $10K amp will fix your problems.

Knowing how easy it is to apply PEQ at the source rendering level changes a lot. It put my fears to rest of any screwy frequency response behavior of wide-range back loaded horns without the use of a crossover circuit.

Marvey · « **Reply #75 on:** March 23, 2013, 09:07:01 PM »

It works

So anyways, the darn experiment worked, much better than I would have hoped. It turned out the comb effect from the interaction between the mouth of the horn and the speaker driver wasn't that bad and was predictable enough from various angles to be EQ'able. (We can still see vestiges of it in the FR graphs.)

The bass group delay from the horn in relation to the mids and treble was not discernible with the 6' BK-16 kit. The 8' Voxactiv's we heard at THE SHOW had a very discernible bass delay with much of Tom Wait's lower register appearing to come out from the horn fractions of a second before the driver. Anax and I pondered if perhaps the Vox's much longer horn path caused this effect. I will say that the 8' Vox was more dynamic and faster sounding. This seems consistent with others who have built the 8' Fostex kit. What makes speaker building fun is that there are a lot of compromises to be made. Decisions are never easy. Improve one thing, lose on another.

So anyways, here is a description of the system setup:

POS Dell Core 2 Laptop feeds PSA PWD2DAC via USB. JRiver MC18 is used to resample x2/x4. EasyQ is used to EQ Mains/Tweeters
PSA PWD2 DAC feeds the Schiit Mjolnir via generic XLR balanced cables
Schiit Mjolnir 3-pin XLR "headout" jacks feed the mains (fostex fe166 drivers) - absolutely no crossover or other shit in between
From the terminals of the mains, single strands of Ethernet cable feed the Fostex T90 supertweeters with one cheapo 0.22uF Bennic cap in series.
Schiit Mjolnir 3-pin XLR "preout" jacks feed in the analog inputs of the Behringer DCX2496.
Behringer DCX2496 feeds the cheapo Hsu STF-2 subwoofer's plate amp. Subwoofer PEQ/XO/delay is performed by the DCX2496.

Costs:

$400 POS Dell laptop
$2000 ($800 alternate DAC)
$750 Schiit Mjolnir Headphone Amp
$500 (Madisound BK-16 Fostex fe166 kit - you gotta put it together)
$200 Behringer DCX2496 DSP EQ/crossover
$380 Fostex T90 supertweeters (optional)
$370 Hsu STF-2 sub (optional)
Cables, adapters, soldering iron, clamps, wood glue, tung oil finish, etc. are extra.

This setup sounded better overallthan any other moderate SPL setup at the 2012 SHOW. I shit you guys not. I'll let LFF, Anax, or Ultrabike (later) to attest to that. It is hard to beat custom measurements and EQ though. It's all about setup and integration, not high priced components. Add the following to be able to do measurements:

$150? ARTA
$5 5 Behringer ECM800 microphone
$99 Microphone preamp
$59 Soundcard

victor25 · « **Reply #76 on:** March 23, 2013, 09:08:30 PM »

Very interesting read Purrin! Just 2 questions if you don't mind:

-How do you measure your speakers? What equipment, position, software etc. do you use?
-What would you recommend the non-DIY'ers?

Marvey · « **Reply #77 on:** March 23, 2013, 09:24:13 PM »

Quote from: victor25 on March 23, 2013, 09:08:30 PM

Very interesting read Purrin! Just 2 questions if you don't mind:

-How do you measure your speakers? What equipment, position, software etc. do you use?

-What would you recommend the non-DIY'ers?

I use an ancient version of commercial measuring system CLIO running on a Pentium 4 PC. I have started to augment the CLIO with ARTA - indicated above.
I would recommend that non-DIY'ers first learn how to use a soldering iron. No pain no gain.

BlackenedPlague · « **Reply #78 on:** March 23, 2013, 10:49:06 PM »

what soundcard are you using?

Marvey · « **Reply #79 on:** March 24, 2013, 12:36:50 AM »

Some cheapo generic soundcard from the 90s that came with the CLIO kit.

Author Topic: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit. (Read 37270 times)

victor25

Re: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit.

Marvey

Re: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit.

Marvey

Re: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit.

Marvey

Re: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit.

Marvey

Re: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit.

Marvey

Re: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit.

victor25

Re: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit.

Marvey

Re: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit.

BlackenedPlague

Re: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit.

Marvey

Re: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit.

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Author Topic: Back to Speakers! And so it begins... again! Madisound BK-16 Fostex fe166 kit. (Read 37270 times)