The amazing sounding, very easy, almost free RME mod! - Page 9

Do the caps need to be polar or non?

Nice photoshop. You have too much time.

Feh, that took like 10 minutes. I'm already not sleeping tonight as it is. Getting gang raped by two clients at once. Wheeeeeeeeeeee!!!!!

Yes. I'm hopped up on caffiene!!!!

The only major difference between balanced and unbalanced is that the unbalanced sacrifices more maximum volume output. About 3-4 clicks on my Grace.

-Ed

Yes, the virtual solder joints are cleaner.

I keeeed. I keeeeeed.

I ordered some silver wire to redo the wiring on mine. Going to make sure they're all the same length this time. For purity's sake. It will make the biggest difference in the world!




For me to POOP ON!

-Ed

mmm, i'm going to bed. now goodnight! and good luck.

may the solder be with you.

don't forget about the guide to doing this. i mean... if you take to long, you'll be owned by emu 1212m

Thanks for that guys, i was going to connect that red with stock wire initially.... not a hard mod at all is it? just the removal of that one op amp and bridging with two capacitors? will more expensive caps help sound quality much? or is it just to remove the DC offset?

Make sure to remove the four little capacitors in the front of the card first. Just use pliersor your thumb, bend then back and forth,until they fall off. Then solder new caps in the back of the card like the pics show.

Use Blackgates if you can. They take awhile to burn in, but they are well worth it.

-Ed

I don't think i'll be able to find blackgate capacitors down here in New Zealand. Would any 50V, 22uF Non-polar Electrolytic Capacitor be suitable? how much better (theoretically) would a blackgate be?

If you can't find Black Gates, look for Elna Silmics or Cerafines. If you can't find those, fall back to Panasonic FG series, which you can likely find.

These capacitors do have an effect on the sound, so it's worth buying good ones. It won't sound as good if you use generic caps (speaking from experience here).

Personally I'd just order Black Gates from one of the suppliers that ships to New Zealand and wait until they arrive to do the mod.

Alternatively, you could use non-electrolytic coupling capacitors, such as polypropylene film/foil types used in speaker crossovers. Beyond about 3.3uF, these will get expensive (3.3uF is probably fine though). If you start dropping down towards the lesser capacitor types (metallized film, etc.), the mod becomes less worthwhile.

Black Gates

I can attest to the quality of the sound improvement the Black Gates will provide for this mod of the digipad!
You will not be disappointed!!!

Slipkid

slippin outa (to) hear
slippin da head into the music
may not come back
ears an beers

"Not a bad idea, and worth trying, but it's not a major change in the overall topology. You've still got tons of feedback to kill the microdetails. But someone should try it."

Wodgy please explain why you think Feedback Kills micro-details. I keep hearing all this fuss about how good no feedback designs are yet every one I have listened to sounded just like they measure Bad. YMMV

the Possible reasoned for Iron dreamers improved RMAA data is yes one less active device in the signal path is going to result in lower noise and distortion, however with a good supply and proper analog design including a low noise Op Amp -120 dB should be realizable.

Glassman is correct long cables and a low current high impedance output can be an issue but perhaps also the capacitance might just act as a LPF and hopefully a first order one

I know the math, and I know it's not supposed to make a difference, but it seems to. Check out Erno Borbely's website for some of his published designs; he always strives to minimize feedback as long as it doesn't negatively affect the measurements too much. (i.e. He seems to believe there is a tradeoff between measured performance and the audible effects of excessive feedback.)

You're also undoubtedly right that a big part of the improvement is because the op-amps have dirty power. Keep in mind this is inside a computer, and the existing power filtering on the card is fairly poor; also, no attempt has been made to separate the analog and digitial grounds. With those handicaps, removing the op-amps is clearly the right engineering choice, rather than attempting major redesign of the board in an attempt just to keep the op-amps in there, but make them sound good.

The other thing is, even in the best circuits, with great power supply design and proper implementations, op-amps are just not transparent sounding. If we went by their datasheets, we'd have to conclude that good op-amps are basically interchangeable, and should make virtually no difference in sound. Your own PPA (which is presumably a proper, careful implementation), demonstrates that this is untrue. Swapping op-amps in the PPA changes the sound. Thus, we must conclude that even when properly implemented, op-amps are not transparent sounding. This is another argument for getting rid of them, unless there is a concrete engineering reason to keep them there.

(I think it's sort of strange that some people argue that capacitors shouldn't be in the signal path, but then have no problems with op-amps in the signal path. Both should be minimized.)

Iron's measurements clearly have not deteriorated (some improved, some were worse) and what's more, the thing actually sounds better. Seems like a good engineering choice to me.