Preamplifier, worth modifying? Pics attached

[east electronics]

i agree .... as a standar upgrade we replace a lot of 4558 or 4560 with 5532 series and that was a drastic improovemnt in the output of a lot of cheap CD players

good to see you bonsai take care

regards sakis

 

[Jay]

Dont really want to spend a lot of cash squeezing juice out of a rock but what do you think guys, is it worth changing a few caps, upping the power supply caps, etc?

You are already on track. No need to throw a lot of money on this preamp. If you have budget, build another better preamp.

Upgrade is better done with the caps in the signal path. The mylar cap (green one) should be replaced with MKP (e.g. the one for the bass control). The ceramic disc (brown) should be replaced with paper cap (e.g. the one for treble control). If there is big electrolytic cap in the signal path, parallel with 100n MKP.

 

[gil1]

Some of the argument here seems to be over price/performance, the difference in price from the 5532 and the opa2134 here in the states is just over a dollar each.
This preamp I got basically just to play with and see how far I can go with it doing a few mods to it, I dont expect it to sound like some of the other preamps I have but it be fun to try.

Jay, thanks for the tips and yes I dont like those green caps either.

 

[gil1]

..... hm...lets see .... adding supreme op amps in a machine that has no tone control bypass switch doesnt acually make real sense

i presume that the benefit of a good op amp will be consumed by the limitations of the tone control

then again upgrading a machine that has such a terible inputy selection and presumambly terible crosstalk figures either from left to right or if more than one active source is conected to it is absolutelly pointless to my understanding ...

either you simply replace the chips and keep it as absolutelly is and may add a few better caps in the power supply where the diference will be bearly audible

or remove the guts from it since its quiet roomy install inside a decent line stage skip the tone control and use a shunt topology relay stack for input selector...this will end up to good hiend machine ...

edit : forgot also the pot hat needs to be replaced

this is how i see it
Regards sakis

The pot hat?

 

[Jay]

The pot hat?

I think "pot that". Not only the potentiometer, but the transformer also hehe