A NOS 192/24 DAC with the PCM1794 (and WaveIO USB input)

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here is a very nice DDDAC "Schaeffer Design" from Switzerland.



DDDAC1794 - 4 Deck
5V DDDAC Power supply
12V DDDAC Power supply
Sowter Outputs Transformers

On the Transformers I got this Feedback :)
Update 11.3.2013: Doede sent me two Sowter 1298 transformers, which he designed as an alternative to the standard coupling capacitor in the analog out line. Apart from avoiding the coupling capacitor in the signal, the transformers also allow using the inverted output of the DAC chips, thus cancelling out even-order distortion. I immediately noticed the sound improvement with the transformers. The music sounded as if the musicians just got a pay increase! The transformers were expensive, but the money was well spent in my case.

:cool:
 

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I order my case at AE Europe, a very good transformer maker in the Netherlands. It is this one

De transformatoren specialist, transformatoren voor iedere toepassing

Only not with picture, but just look at my build DAC's (2 already). Now both have there mundorf silver/gold/oil cap so soon I can make a real good review between on deck, and 4 decks.

Still a small question. If the length of the cable doesn't matter, is it "bad" for the sound to use your spdif input? Because then there are some relais in the digital signal path. My thoughts were....less is more, but if there isn't any differance.....
 
Jan,

I'm using Doede's SPDIF board with my DDDAC and it sounds excellent. I have restricted it to 44.1k and use the onboard clock for re-clocking my SONOS ZP80 Streamer. At the moment, I prefer the SPDIF to using the WAVE I/O with a dedicated PC streamer. That may change once the PC streamer has a linear PSU though.
 
On the Transformers I got this Feedback :)
Update 11.3.2013: Doede sent me two Sowter 1298 transformers, which he designed as an alternative to the standard coupling capacitor in the analog out line. Apart from avoiding the coupling capacitor in the signal, the transformers also allow using the inverted output of the DAC chips, thus cancelling out even-order distortion. I immediately noticed the sound improvement with the transformers. The music sounded as if the musicians just got a pay increase! The transformers were expensive, but the money was well spent in my case.

:cool:

The Sowter transformers are on my wish list. :)
 
For test purposes I have been going beyond 1 meter without any issues....

The short cable is just cost saving... no just kidding :) if you need a longer cable, I am happy to make one for you!

Doede

Hi,

The shorter the cable the better, this is same as with all cables. You can notice sound quality decreasing when using longer usb cables, same applies to i2s cables. I am using a cd tranport with philips cd pro loader and put out i2s to a modified tent dac in a seperate box; you can notice sound quality decreasing with longer cables. However using longer i2s cables might at first not be audible, when your system developes it can become the bottle-neck.

If you want to test this try an usb extension cable, the difference must be noticeable.

Regarding my dddac setup: I plan to integrate it with an alix pc board in one case, this keeps the usb cable also very short, I can even solder the cable directly on the alix and waveio so no connectors are used.

Do not forget: a lost bit on the way to the dac can never be recovered. There is a lot of debate about Bit Perfect output of the usb stream but lets not forget the influence of the cables!


Kind regards,
 
I2S cable length

I'd like to move the Wave IO Board to the back of the enclosure, along side of the main DAC baord, rather than directly in front as the short interconnect cable implies such that all signal inputs and outputs are on the rear face. Is there a limit to the I2S cable length from the USB board to the main DAC board before problems occur ?

Regards

For USB a good quality one will be a safe choice. Longer than one meter is only adviseable on Doede's recommendation.
I2S? Please as short as possible. A safe max. ,anywhere on the Net advised,
is 10cm! With shielded 50 Ohm U.fl cables you will have a litlle bigger margin. All wires or cables of exactly the same lenght.
 
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I2S Length

For USB a good quality one will be a safe choice. Longer than one meter is only adviseable on Doede's recommendation.
I2S? Please as short as possible. A safe max. ,anywhere on the Net advised,
is 10cm! With shielded 50 Ohm U.fl cables you will have a litlle bigger margin. All wires or cables of exactly the same lenght.

Thanks Ed, I don't think i'll need longer than 10cm in any case.
 
@Ian,

I first only used also Doede's SPDIF input, without clock, and a Sonos ZP90. It sounded good. Then, I sold the ZP90, got myself an extra Macbook Air for music only. It really sounded better, but the greatest jump forward was Doede's psu for the Waveio. The DAC played already with a Tentlab psu, so that was ok.

My opninion is/was that leaving the spdif unit out of the i2s line it would sound better...but I didn't test it yet...:)
 
Hi Jan,

Yes, I had thought about the i2s going through the SPDIF board and whether it could be affecting the sound, if you test it be sure to let us know. I've also thought about adding some sort of input selector but being a novice at this DIY I have no idea of what I would need.

The ZP80 I have is not standard, the switching PSU has been removed and it is now fed by two seperate power lines using Paul Hynes linear regulator boards. The SPDIF output socket has also been replaced with a true 75ohm connector.
 
There are more methods than one to connect through the DDDAC USB driver. But I think that JRiver asks if you want to use the WASAPI way. Which happens to be the best sounding mode. So I'm assuming you did hear the full potential of pc.

JRiver is using WASPI-Event Style. One thing I have changed is the USB cable to a much shorter one, 1 meter, which has made a difference.
 
Hi Bas,

The streamer isn't actually mine, it's a friends who came to listen to the DDDAC last weekend. The media player is JRiver and it is set-up to output through DDDAC USB driver.

...and I am that friend. We tried my streamer through the SPDIF input first and the sound was not as good as IanS1 Sonos. Since I have left he has tried it through the USB and WaveIO and much better he says. The streamer runs off a SMPS and now IanS1 has built a linear supply and very good now and want to hear myself now!
 
I did a lot experiments on the streaming front end. many different motherboards, windows version, mac etc. many differrent software player, cmp, cplay, jplay, jriver etcetc. At the end nothing is more natural sounding, transparent and dramatic than an Alix 1 Board and sotm isb-card with Mdpup, which is an idiot proofed Linux version and where you can use mpad, a very nice iOS based GUI for you ipad. This kills any windows machine or Sonos...I tried a Modified ZP90 as well. It was modified to use external clock though, not i2s out. if anyone has a modification for i2s out, i could try that.
 
I did a lot experiments on the streaming front end. many different motherboards, windows version, mac etc. many differrent software player, cmp, cplay, jplay, jriver etcetc. At the end nothing is more natural sounding, transparent and dramatic than an Alix 1 Board and sotm isb-card with Mdpup, which is an idiot proofed Linux version and where you can use mpad, a very nice iOS based GUI for you ipad. This kills any windows machine or Sonos...I tried a Modified ZP90 as well. It was modified to use external clock though, not i2s out. if anyone has a modification for i2s out, i could try that.

I guess you are right...........

Regards,

An alix/mpdpup user ;-)
 
Come on guys, this thread is going way off topic. Let's get back to DDDAC.

Anyone tried the Sowter output transformers or other transformers with the DDDAC?

My Alix/mpdpup is connected to the dddac with two boards.
I use the dddac power supplies 12v and 5v with minor modifications (black gate non polar antiparallel on output, film cap not soldered and elna silmic for the big caps.)
The alix is fed with a tent power supply.

Two extra boards with sowters are on their way to me (hopefully soon).

I also plan to mount tent shunt regulators on the dac boards, I wonder what that will do with the sound?

The sound is already pretty good and is a close match to my cd player/ dac combo but I hope this will improve with the planned modifications to exceed the cd player/dac performance ( I have a feeling that it will :))