dddac1543 mk2 ** modular design ** USB & SPDIF input **

[12 Cents]

Originally posted by dddac
By the way, I just finished my set up for an audio server, streaming into the USB input

can be looked at at my site. look for banner dddac1543mk2 than in frame left click USB Server ....

or go straight with this link (no frames...)

USB Audio Server


doede

BTW that album (Katie Melua - Piece By Piece), besides being beautiful music, seems very well recorded to me, but also overproduced, have you noticed the slight reverb on the esses (S-Laute in german), the sibilance IMO?

[Bas Horneman]

the sibilance IMO?

I think so too..good recording it seems..but overproduced..that sums it up pretty good I think.

[Zodiac]

Originally posted by Zodiac
After reading so many things about USB - it's amazing, the best thing since sliced bread, etc... I decided I should try it out for myself and compare against my base system to see whether it met it's reputation or whether, like most things in audio, it was a load of hot air. Music used was varied, ripped using Plextools and losslessly encoded. Music played off a Mac Mini

My base set up is Cyrus Diskmaster --> Benchmark DAC1 --> Active XO ---> Pass Labs Aleph3 / UCD 180 --> Linkwitz Orion

I built myself a USB-SPDIF converter using a PCM2706 (thanks to TI sample programme), powered off bus. Sound was long way behind Cyrus/Benchmark combination, bass 'one notey' to the point of being unlistenable and a very high audible noise floor. Positives, a bit more detail it seemed in med / high frequencies, but to be honest I couldn't listen to more than 15mins without switching the damn thing off.

Then I built a USB front end for my TDA1541 nonos dac (PCM2706 outputting straight I2S), which hitherto was using a CS8412 receiver with local clock, I2S reclocking based on Doede's original schematics and DEM clocking. When I was using this with the Cyrus I actually preferred it to the Benchmark. With the USB front end - first impressions are that bass 'one note' sound is completely removed, actually it is more chunky and rounded than that from the Cyrus/Benchmark. Also the high noise floor seems to be ameliorated, but it still seems higher than when fed by the Cyrus. There's more musicality and flow to the music, but less dynamics and less energy. Detail during busy patches seems slurred. Overall a less satisfying experience!

At this stage I can think of a few tweaks I can make to the USB front end - maybe Tent Labs 12Mhz oscillator (ordered, but not yet arrived) and re-implementation of DEM clocking driven off a buffered bitclock will restore things? Power supply is current sourced shunt regulator, so not that much improvement I can make there....

One things for certain though, having all your cds available at the touch of a button is the dogs danglies!

Well, some progress to report...implemented DEM clocking off the PCM2706 MCLK and swapped out the standard TDA1541 for an S2

Impressions relative to Discmaster / Benchmark:

+ve's: bass more solid and defined, notes have more shape to them. More musical. Low level details not previously apparent now audible.

-ve's: not as transparent, reduced 'air'. higher noisefloor

I actually think the first -ve is related to the old multibit dac vs new deltasigma dac and not related to USB / SPDIF comparison...

All in all I actually prefer the computer as front end now (though the difference is NOT night and day as some would have you believe and my TDA1541 implementation is quite full on in terms of power supplies) !! So big step forward. Next steps are implementation of the 12mhz Tent clock (just waiting for a few bits from farnell). Anyone have any ideas about isolating the computer ground from the dac ground??? BB150's ??

[summilux]

Boy, would I ever WANT this to work the best on a Mac. On my iTunes (6.02) under Preferences/Advanced I can disable the iTunes volume control and increase the streaming buffer, under Preferences/Playback I can also disable two "Sound Enhancers". Maybe this would help?

Jonathan

[velicko]

In the file dddac1543mk2ver50.pdf there are layers design for all three boards.
Does anybody have separated layers so I could build PCB-s myself.

If it is not problem, please do send me to velicko@gmail.com.

I could work it out in Photoshop, but it would save me much time if I could get separate pictures for all layers for all three boards.

Thanks much.

[pburke]

Originally posted by velicko
In the file dddac1543mk2ver50.pdf there are layers design for all three boards.
Does anybody have separated layers so I could build PCB-s myself.

If it is not problem, please do send me to velicko@gmail.com.

I could work it out in Photoshop, but it would save me much time if I could get separate pictures for all layers for all three boards.

Thanks much.

why don't you just buy a board? We're not talking about a $3000 Levinson product here.

[velicko]

Originally posted by pburke



why don't you just buy a board? We're not talking about a $3000 Levinson product here.

I do not live in EU, and I am tired of problems with customs.

For example:
Unfortunately, I ordered free samples from TI, and after few days samples arrived to customs.
I got package after few days, and after I paid more than 80 EUR just for custom expenses.

Maybe for "just PCB" it would be different, but I really do not want to go through all their complications...

Never mind, I'll clean the givven picture with photoshop.

Thanks anyway.

[fmak]

[QUOTE]Originally posted by velicko
[B]


I do not live in EU, and I am tired of problems with customs.

For example:
Unfortunately, I ordered free samples from TI, and after few days samples arrived to customs.
I got package after few days, and after I paid more than 80 EUR just for custom expenses.

-----------------------------------------------------------------------------------

This is mostly due to the incomprehensive way in which US comapnies manage their postings; applies even to the EU!

If they just put samples in an evenelope with a declaration of neglible value, this would just get thru' the post. Instead, they use these expensive international mailers who actually charge for informing the tax authorities. Some even handle tax like they are part of government!

I am very cautious about ordering from N America. About 10% of the companies are sensible and use USPS which is perfectly good.

[pburke]

Originally posted by velicko



I do not live in EU, and I am tired of problems with customs.

For example:
Unfortunately, I ordered free samples from TI, and after few days samples arrived to customs.
I got package after few days, and after I paid more than 80 EUR just for custom expenses.

Maybe for "just PCB" it would be different, but I really do not want to go through all their complications...

Never mind, I'll clean the givven picture with photoshop.

Thanks anyway.

not sure what you are afraid of - Doede even sells his stuff for cash in an envelope, and I doubt he'll ever use something like FedEx or UPS that'll force the shipment thrugh silly customs channels.

Why don't you ask him? his DAC chips arrive in the US in a little cardboard box with a few stamps on them. I'm sure a PCB will fit into an even smaller envelope.

Peter

[tuyen]

Hi all,

I have running a 120chip (10 modules) DDDAC1543 MKII at the moment with Doede's USB module too (PCM2707) connected via I2S. Has been working wonderfully and sounds really nice. I recently purchased a jkeny hiface USB I2S unit and trying to replace it with Doede's USB module. I am getting just mainly loud static noise at all sample rates. I can confirm both the jkeny and the dddac towers work but when connected together (although it could be bad incorrectly though.. ) it is not. I am not using the MCK signal from the jkeny. Only the BCK, LRCK and DATA signals..

Has anyone had the same issue or knows the reason why? There was some mention of needing a opticoupler/buffer which could help?

Thanks all,
Tuyen