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

Mario - I am building this too but on this link I am confused about the PSU needed for the Allo. Did you power it the Allo, Pi and HiFi Berry using the same single 5 v PSU?

DDDAC 1794 BerryStreamer met Allo Isolator


Thanks
Simon

hi simon,

i was confused too after reading this article. i thought that i could run ROON with this. but it doesn´t work because for roon you need somethng more:-(

to your question: i take the PSU from the Wave IO (Doedes one) and turned it to 6 V for the Allo isolator. For the RPi3 i bought a new one with 5,3 V and 3A (just to be shure to have enough power :). the Hifi berry gets his power from the isolator.

hope this helps, mario
 
hi simon,

i was confused too after reading this article. i thought that i could run ROON with this. but it doesn´t work because for roon you need somethng more:-(

to your question: i take the PSU from the Wave IO (Doedes one) and turned it to 6 V for the Allo isolator. For the RPi3 i bought a new one with 5,3 V and 3A (just to be shure to have enough power :). the Hifi berry gets his power from the isolator.

hope this helps, mario

Hi Mario

Yes it helps :D

So just plug all 3 boards together and no need to modify anything and then connect the 2 PSUs as you stated correct? When I read that website it was not clear if any mods are required on the boards so why I ask this question

I plan to run Roon on this as an endpoint using the right software of course

Thanks for your help
Simon
 
Hi Mario

Yes it helps :D

So just plug all 3 boards together and no need to modify anything and then connect the 2 PSUs as you stated correct? When I read that website it was not clear if any mods are required on the boards so why I ask this question

I plan to run Roon on this as an endpoint using the right software of course

Thanks for your help
Simon

make the connection from PSU to the isolator before pluging the boards together.
on what hardware do you run the ROON-core?
mario
 
you measured the POS and NEG against COMMON or against each other? The latter case would be ok. measuring against COMMON I would expect 4 values of course like 2.7 2.8 Volt. check this first pls

Sorry been out of the loop for a while. Measurement from common to positive and negative come out at:

Right channel - com/pos = 2.825v, com/neg = 2.732v
Left channel - com/pos = 2.725v, com/neg = 2.743v

Music distorted and I've put the original capacitors between the output and rca connectors.
 
Sorry been out of the loop for a while. Measurement from common to positive and negative come out at:

Right channel - com/pos = 2.825v, com/neg = 2.732v
Left channel - com/pos = 2.725v, com/neg = 2.743v

Music distorted and I've put the original capacitors between the output and rca connectors.

In your previous post you wrote "I see 6mV on the right channel and 2mVon the left", but here you have 93mV difference on the right channel and 18mV on the left channel.

You also wrote that the issue appeared with a broken RCA connector. How does the capacitor play into this now?
 
Thanks for sharing this long term results at the forum! Indeed Paulus recently mentioned also that burn-in takes a longer time as usual or expected, but it is worth to keep the dac switched on, 24/7 in the beginning, for at least a few weeks. If you only listen 1 hour a day, it will take you months ;-)


What happens during "burn-in"?
Is it something you can measure......or only hear?
If sound change during "burn-in".....is it always a change for the "better"?


I stream music via Tidal and I have a "HiFi agreement" which means that I get CD quality (16 bit / 44 kHz) or higher (24/96 or 24/192). 24/192 requires that I have a DAC which can decode MQA.


Is your DAC recommended for my purpose (decoding MQA is not a must as the node decodes 24/192 to 24/96 by software)?
 
Does anyone have a DDDAC mainboard to give away?

I am looking for the newer (blue board) that has the "active" clock delay circuit. I am only interested in I2S input. SPDIF / Tent Clock is not relevant for me. Contact me by private message if you have one to sell. Please indictate price and condition of the board. Thanks!

No one?
 
Goodbye Old Friend !

My old friend is leaving me to another good home.

This was the case and power supply I built for my first DDDAC which started it`s life with version 1 main board and 4 Dac boards. It now has 4 Tent boards and the latest mainboard.

It sounds almost as good as my 16 stack made with the pre Tent boards after running for a day.

Can someone get 16 Tent boards running and let me know what they have done because stacking them up really does improve the sound quality :)
 

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Can someone get 16 Tent boards running and let me know what they have done because stacking them up really does improve the sound quality :)

I haven't done it, but I am thinking about it. I guess the limit is related to how the digital signals travel from the mainboard to the DAC boards, and it may be too long a trip from the mainboard to the 16 DAC. Would it help to mount 8 DAC boards above and 8 DAC boards below the mainboard? DAC sandwich anyone?
 
I haven't done it, but I am thinking about it. I guess the limit is related to how the digital signals travel from the mainboard to the DAC boards, and it may be too long a trip from the mainboard to the 16 DAC. Would it help to mount 8 DAC boards above and 8 DAC boards below the mainboard? DAC sandwich anyone?

I have a 16 stack Dac playing fine using the old type boards so the I2s length is not a problem.

I never got 16 Tent boards to work, it made the same distorted noise when trying to run 8 old type boards using the red main board.
The Tent Powered boards seem to present a bigger loading of the I2s than the old boards but I never found out why.
I even tried to change the decoupling resistors from 15R to 100 and 1K but still couldn't get it to play.
It may need paralleled buffers with their own power supply regulators just before it goes to the Dac boards but that is beyond my capabilities.
 
I have a 16 stack Dac playing fine using the old type boards so the I2s length is not a problem.

I am assuming this is with all 100Ω reistors in the I2S input of the DAC boards (no 1kΩ for the clock delay).

I never got 16 Tent boards to work, it made the same distorted noise when trying to run 8 old type boards using the red main board.

The stock red mainboard does not have the "active" clock delay. It achieved the clock delay using an RC network (using a 1kΩ I2S coupling resistor instead of the 100Ω). I guess active circuits of the newer blue boards works as a buffer for the I2S and therefore allows driving more DAC boards.

HOWEVER, looking at the schematics at the DDDAC website, the only difference in the I2S inputs of the different DAC board versions I can see is the coupling resistors (100Ω/1kΩ/100Ω in the original version for the red mainboard, then 100Ω/100Ω/100Ω in the later version for the blue mainboard, and then the current "Tent" DAC boards don't have the coupling resistor values specified).

But since your tests with different I2S coupling resisors did not change anything, I'd tend to think the difference is elsewhere. I would not be surprised if the newer "Tent" DAC boards would consume more power. They might hit the current limit of the power supply a bit earlier than the "non-Tent" DAC boards. Have you looked into this?