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

by the way... anyone who has the opportunity to test/listen on the new Q3 FiFoPi using Tentlabs XO clocks (should work now because of no need for OE), compared with the Accusilicon, please post your experience?

thx!

Hi Doede,

A Q3 fifopi is on it’s way to me, now resides in customs in the Hague. :(
Maybe (most probably) the first one in the Netherlands :D

I do not use Tent XO but the Andrea Mori SC-cut XO.

By the way, in the pictures the latest version of my streamer part with battery supply and supercaps.

Regards,
 

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Good News,

Dick from Audio creative (Link to their Site) tested the new Q3 FiFoPi with the DIP-8 size Tentlabs XO clocks and used a DIP socket in between which is a great and clever trick to overcome the fact Ian moved the middle pin away in the new version. Below the DIP Socket he soldered two wires from the clock to the outer pins.

This combination works sound wise great with the DDDAC1794 setup – so good to know for everyone liking the Tentlabs XO clocks or even having them lying around from other projects :cool:
 

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@Supersurfer: A fellow moOde user!

The software that handles the audio with the moOde distro is MPD.
Assuming you have a stock 6.7.1 distro without mods.

Because the outputrate differs from the decoded rate, the output device has informed MPD that samplerate isn't supported. Thats why MPD downsamples.

First place to check is what the command alsacap tells about the device capabilities.

This will go very fast very OT, maybe an idea to move the question to Moode Forum ? moOde has a very active community.
Has anyone been able to install and use Alsacap on rpi+Volumio?
Are there any instructions how to make / install / run Alsacap around please?
Thanks a lot
 
I have a question. On my DDAC 1794 the balanced outputs are connected via four capacitors (Jantzen Z-Siver cap 4.7uF). Is it a mistake? Can I connect them without a capacitor or a transformer (directly from a PCB) and only the singe ended outputs remain connected via two 4.7uF capacitors?
 
I have one more question. My friend has a two boards version, and a Cinemag 600/600 transformer at the output. The transformers are terminated on the secondary with 1k8 resistors. It doesn't sound nearly as good as my DAC with four boards and capacitors at the output. I temporarily replaced the transformers with capacitors and now it plays great, as does my DAC. What is the problem here?
 
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Correct

You are not comparing like for like as the more boards you have the better the sound.

Why not put his transformers into your dac and try it?

It’s known that the best sound is direct then transformers then caps but you will need to try and see what’s best for your ears and system

System matching is important too
 
sorry, this is very off topic - so please look for a specific thread (or start one)
thanks :eek:
my bad Doede.. but I would encourage others to check their status with Alsacap (not sure how I made it really.. I used some commands from terminal make / gcc / ./ to run..) as it appears my setup (rpi+kali+dddac via i2s) is not limited to 192000 files with latest Volumio. Now will need to tinker how to extend compatibility..
 
What is the purpose of these resistors? I would think the load seen by the DDDAC would be too low due to these resistors.


These transformers have a peak + 3dB at 200kHz with a 10k load. For a flat frequency response, the load is 1k8. I will try with no load, then 10k, 4k7 ..., because I also think that 1k8 is too much load for DAC with two boards. I have no experience with line transformers, so I'm looking for advice. And if I can make it sound better than my device, I'll take the transformers too.

PS

I'm not sure what the peak is with no load on the secondary, so I'll probably start with 20k because the input impedance of the preamplifier is usually 20k-50k
 

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