Aikido question

[kacernator]

Still tweaking my 4xECC88 Aikido preamp. I am still not sure about the PSU capacitance. I have my preamp connectied in this topology: Soundcard-Aikido-Stereo Reciever (Soild State).

Right now I have 47uF - 5H - 440uF for each channel. Withou Aikido preamp in signal chain the overall sound has more slap, more solid. I try to raise the 47uF to 110uF and it helps. So I am thinking....do I still havent enough PSU capacitance if raising it brings more slap more solid tone?

Is it possible from Aikido (or generaly tube preamp) to have same slap and solidness as solid state? Or tubes will always have little looser feel than SS?

Is it ok to tweak Aikido this way - I mean I just add it to the signal chain, so I tweak that it should sound close with preamp as it there would be no aikido.

[Stixx]

Is it ok to tweak Aikido this way - I mean I just add it to the signal chain, so I tweak that it should sound close with preamp as it there would be no aikido.

It would be disappointing when you can't tell anymore whether your Aikido is in the signal chain or not...

Generally speaking it is ok to tweak an amplifier to make it fuller sounding (or whatever), but I think the rest of your signal chain seriously limits your chance to evaluate the sound of your aikido...(especially feeding it from a soundcard).

Any well built tube preamp can have the same impact and solidness as a solidstate amp...and then some!
Tubes in most cases sure will sound different...but that's why we are building tube amplifiers!

Of course also the tubes used can make a difference, as does the parts quality and so on...

[kacernator]

Yes I know.

I should propably tweak the values of filter caps to suite my tastes, as I cant find any "formula" how to determine the optimum PSU capacitance which you should use.

So if comercial manufacture builds a poweramp - car radio, active computer speakers they choose their PSU capacitance by ear? I hardly think so.....really there is no way how to measure or simulate how bug filter caps should be to be sure you have enough?

[euro21]

Try PSUD.

http://www.duncanamps.com/psud2/index.html

The "formula": C - L - 5*C

[kacernator]

I have this software and it does not tell you that you have enough capacitance to make the circuit sound right.

[Stixx]

kacernator,

no software will tell you how much capacitance you need to make it sound right...you can just simulate the most effective way to kill ripple and have no ringing etc. I think your ripple values are low enough not to effect the sound quality too much, but what you are after is a formula for the best recipe for good sound.

To my knowledge there is no such recipe other than probably a lot of people have their own favourite way to build a psu and make it sound right (their way).

It is not just psu capacitance that has an effect on the sound...it is the entire topology, the tubes and parts used (oops, I said that before ), so commercial companies not only play with the capacitance. They just have the experience what sounds good and what not...and experience comes from trying and years of building stuff.

I don't want to sound overly smart since MY experience is not that big after all, but having built a few tube headphone amplifiers I spent a good deal of time "tweaking" them...and again, it was not just capacitance...

[euro21]

"the circuit sound right"
Hmmm... It's very subjective thing.

Is ECC88's sounds right? Yes, my NOS Tesla (gold pin, yellow printing) E88CC's are good tubes.
What about resistor sound quality? ... Yageo vs. Riken, Kiwame, Holco...
Most important thing is coupling capacitors. ... WIMA vs. Mundorf, Jensen, teflon caps. ..

Regulated vs. unregulated PSU....
AC or DC heaters...
Tube rectifier, SS rect., hybrid rect. ...
HV supply capacitors: usual Yageo vs. Panasonic, Elna, Rubycon, Balck Gate...

etc. ... etc.