Turtlerock Forum

Hey Guys,

Got around to recapping the power supplies of a few synths, no surprises there - they sound sweeter now, and then decided to re-cap the preamp in my 1972 fender rhodes suitcase...

Thing is, when it was done, i noticed a bit more bass, but the sound was more 'distorted' and harsh as in driven in the mids and highs... at first i though maybe the preamp is working better so the pickups which are fairly close to the tines are now overloading it... BUT i played it today and it sounds sweet and wonderful and not distorted at all..

Question being - do caps need to be worn in and can they sound harsh until they have had some voltage running though them??

h.a.r.r.y.a.r.v.a.n.i.t.i.s

some older stock caps may have to form or re form and that happens the first time you turn them on , but in my experience this is for big value power supply type caps.

so presumably some new caps do this a well ?

but i somewhat doubt it would be an issue with the smaller sizes we are talking about

that said .. sure why not ?

well i can think i thirteen dozen other things it may have been as well .. but your empirical evidence says caps
so sure why not

or it could have been your ears and brain ...

or a perhaps a cap on your ears and brain to keep the sun off ..

Point being that for a standard thing caps have been sold preformed as the normal thing for ever so they should never need wearing in

while it is possible yours were not ..and they starved everything as they formed under voltage load and caused distortion in the mean time

i have only ever seen it once with really big ( nos and old shelf ones ) on a power amp I recapped
( 20 years ago )

sometimes i turn really old things on with a variac for the first time just to see whats what and the caps reform or remake or what ever the term is

and performance does indeed get better as you get up to voltage and things have been warmed up .. so there is theory in your madness harry

but i do it more to see what is going to smoke then to burn things in

lots of stuff smokes on old things

so as an answer .. as a rule new caps do not need to be worn in
( of course to every electronic rule there is an audiofool exception )

Hey Rob, Rick..

Okay, seems that this rhodes sounds slightly different every time i play it - sometimes sweet, sometimes a bit harsh.. Today it is a bit harsh. So - perhaps the capacitor replacement kinda made the preamp more efficient - im getting much more level (it was always quieter than a friends identical piano) and a bit of extra bass - now the pickups are overloading it (as they are quite close to the tines)...

would bad power supply caps or those in the amps explain why it never sounds the same.. It has the same kind of harshness that one of my old synths had until i re capped the power supply..

on it goes...

h.a.r.r.y.a.r.v.a.n.i.t.i.s

Harry, what caps did you put in it?

Hey Ross,

I just put some Nichicons in that i had lying around.. it also required 6 bipolar caps.. didn't have any bipolar's lying around though... i used the cheapass jaycar ones..

btw.. got to use one of your compressors at a friends studio a while ago.. couldn't help myself and asked if i could have a look inside.. i'm guessing it was a variant on a la2a but solid state, transformerless, and different opto, and really high quality parts (caps, resistors) - it is a really nice unit!!

h.a.r.r.y.a.r.v.a.n.i.t.i.s

Harry, thanks for your kind words.
But getting back to your original question and the reason for asking what caps you used.
The short answer is yes electrolytics do take time to wear in but the length of time it takes and the way the sound changes as they burn in is dependent on the the actual cap.
Some caps develop their fixed sound after a very short burn in and others can take a month or more.

There are of course many people who think that the concept of different capacitors having "different" sounds is a load of old cobblers.
I happen to disagree with them.

Hey Ross,

thanks for confirming that i'm not going crazy and imagining things - this was definite - first 20 mins sounded harsh, next time i turned it on... normal...

Every time i've recapped a power supply (not audio path) it was instantly better..

Want to re cap my space echo next (sound amazing, but loses a fair bit of bass) but it's pretty messy in there - tight wiring looms, hard to get the boards up.. and if it aint broke.....

btw, was thinking of getting one of these:
http://www.peakelec.co.uk/acatalog/jz_esr70.html

does anybody have experience with these??

cheers

h.a.r.r.y.a.r.v.a.n.i.t.i.s