sort of Ultimate dac

[Koenjer]

Hi there,

Last months I tried to make my own "ultimate dac"
See the attached pictures.

Specs:

PSU: 220v Primary filter
separate +/- 18v psu for analog audio
separate +5v psu for digital parts

Source:
- Musiland monitor - with modified I2S output.
- 24mhz dedicated VCXO clock, powered with shunt regulator also feeding the musiland

Dac:
BB PCM1794 - powered by Tentlabs Shunt regulator
I/V: Burson audio +/-18v
Output: Burson audio +/-18v

Preamp:
BB PGA2320 - powered by Tentlabs Shunt +/-15v
Elna Silmic II in signal path.

It's still in its first playing hours so I would make my opinion the next weeks.

If someone has some comments or suggestions, please let me know.

http://img221.imageshack.us/img221/2103/imag0014x.jpg
http://img130.imageshack.us/img130/6148/imag0015m.jpg

 

[jitter]

Looking at the pictures, it looks neat. The only thing I wonder about is grouding because you have quite a number of PCBs and PSUs. It's easy to go wrong there. A very interesting article about this subject is this: http://www.diyaudio.com/forums/diya...udio-component-grounding-interconnection.html.

 

[qusp]

also just wondering, you seem to have room to mount the toroid normally, but instead you have turned it on its side against the wall and its pointed straight at the rest of the PCBs, isnt this the worst orientation you could have done, was this really necessary? the magnetic field projects out the top axis of the toroid worse than any other direction. nice build though

 

[Koenjer]

Looking at the pictures, it looks neat. The only thing I wonder about is grouding because you have quite a number of PCBs and PSUs. It's easy to go wrong there. A very interesting article about this subject is this: http://www.diyaudio.com/forums/diya...udio-component-grounding-interconnection.html.

Thanks for the info. Right now the dac is dead silent. I have been thinking about a screen between the transformers and the circuitboards.

 

[Koenjer]

few weeks later

Well it had it's first burning-in hours.

- It's ok, but I have the impression I'm missing some crispy High's.
- Detail is very much OK.
- Trying different drivers from musiland. (if some one recommends a driver, please let me know)


Work planned:
- Next few weeks I will re-mount the toroid and make an steel separation wall between the transformers and the circuit boards.

- I'm also planning to rewire the system after reading the "audio component grounding" and fitting an I2S isolation.


If someone has some ideas why i'm missing some crispy highs, please let me know.