Comments on: Doing your own DAC mods: a Primer

By: Bob Cleary

Bob Cleary — Mon, 30 Jul 2012 21:42:58 +0000

That Pyramid supply comes with a schematic and should not take a lot of work to change the output, you could probably just change the zener from 12 volts to 9.1 volts and adjust the pot a little..
Just be aware that if you were to modify it down to 9v you could not draw the full rated current because the supply would overheat. These applications usually take very little current so you would be ok as long as you did not try and take more than a half amp or so.

By: 405line

405line — Sun, 29 Jul 2012 22:07:48 +0000

I use the hifi diy1793 dac but many of my comments/observations are on this dac however i think they are similar in there basic topology, i bought it because i couldn’t find a good reason why it shouldn’t sound decent, it’s made from good capacitors resistors etc and uses Burr-Brown parts too.

I modded it with 40,000uf off the PSU which is an old unregulated robust variable voltage bench supply 25v@8 amps, a 10H a 53 ohm hammond “gorrilla” choke then 2 voltage regulators modded with 33,000uf (variable values) on the input and outputs of the 2 voltage regulators and about 120,000uf of (distributed values) bypasss/resevoir capacitance soldered on a flying lead to the pcb where the original 220uf input cap is located on the PCB and also bypassed this point with 100nf and 470nf and some 4000uf of electrolytics made from 1000uf caps and some bypassed with sets of lower value (various types) caps and also multiple different value ceramics on the actual power pins of the 2x mono opamps adapter via a short jumper all diiferent capacitances raided from dead old hifi athough i bought some new ones for the double voltage regulation system i am using. The DAC can run for about 10-15 seconds when disconnected from the DC jack…!!!

I used to use a float charged lead acid cell using a harbour freight automobile float charger but needed more supply voltage so it had to go.

Remember if you use one types of DAC they have a polarity protection diode which eats up about 0.8 volts of any voltage you feed them..i am running my dac at 15.9 volts as the virtual ground splits this in half to feed the 5v DAC psu line so as you can see you are not getting a good dropout voltage for the 5v regulators to “feed” on if you use 12v…2v -.8=11.2/2=5.6v not good, not when i looked up the specs of the voltage regulators used, it needs 1.2 volts difference…the diode problem which if you are brave can be worked around by simply bypassing it as I did with mine.

Modded the op amps with opa627/bm/bp running 10ma class into a 1M ohm input impedance valve buffer all connected with van den hul d102 which cost more than the DAC.

I wrote this after seeing the posters comments about PSU upgrades on what are simple DACs that no one in their right mind should take seriously but there’s always that crank…sounds is really great good as a basic DAC and can be improved substantially with some mods..I can certainly hear many more subtle background details in songs, bass is more tuneful and extended, more depth/space to recordings etc..surprising what a little bit of reading (actually quite a lot of reading) a big choke and some capacitors can achieve.

By: Soldermizer

Soldermizer — Tue, 20 Mar 2012 03:35:38 +0000

About a year on, and I’ve had good results with my (simple) mods. The output caps have been either Russian PIO or more recently, the Mundorf silver-oils mentioned earlier. Also some months ago I bought a 12 Volt car battery whose “current” duty (bad pun I know) is solely powering the Muse DAC. It sounds excellent. Honestly, though, I can’t say better or worse one way or the other, having no way to A/B things. However, i still have the default power supply so maybe could switch that in/out with the battery: that would be a good test.

By: John Reekie

John Reekie — Sat, 28 Jan 2012 13:02:58 +0000

Daniel, Miguel: thanks for your questions, but I think we need to keep questions closely related to the content of the article. 🙂

By: Miguel Casellas

Miguel Casellas — Wed, 25 Jan 2012 23:14:56 +0000

Hi,

Heres the thing:

I´m looking for the best choice of a set of speakers that i would hope you can help me with:

1.- Golden ear Triton two
2.- Salk Signature Sound Songtowers
3.- Grant Fidelity RBS-1 Reference Morel Bookshelf Speakers

Also I´m looking for the best choice between these two:

1.- Cambridge DACMAGIC
2.- Grant Fidelity TubeDAC-11 D/A Converter

Thanks and best regards

Miguel Casellas

By: Daniel

Daniel — Mon, 23 Jan 2012 21:27:17 +0000

Thank for your reply, just more question: Will it work with my PC? My soundcard (SB Live!) doesnt have SPDIF out, however I found one on my motherboad (optical out as well).

By: ainsley

ainsley — Mon, 23 Jan 2012 00:05:02 +0000

The Fiio and Xonar have many other features besides those of a DAC, therefore it’s probable that additional processing is involved and sound quality will be compromised. The Muse DACs only perform one function and are therefore more likely to provide better performance.

By: Daniel

Daniel — Sat, 21 Jan 2012 18:39:18 +0000

Hi,
would Muse TDA1543 or PCM1793 DAC outperform Fiio E10/ASUS xonar U1?
Thx

By: ainsley

ainsley — Sun, 29 May 2011 09:16:03 +0000

The Pyramid has been used with 12v devices with no problem, BUT since writing the article I have learned that the amount heat generated by the higher voltage is not desireable with this DAC particularly with the stock enclosure. A 9v power supply is a safer choice.

By: John Reekie

John Reekie — Sun, 29 May 2011 05:25:16 +0000

Oh… My bad, I’m the one who added the link. I guess that’s “12V” as in car systems, which are typically assumed to be either 13.8 or 14.4V. You’d need to check the specs for the DAC that you’re using to see if that voltage is in tolerance.