Recapping advise for an old amp

[Phorize]

I used to doubt that but was utterly cured by the prospect of a recap on my old accuphase e202. Parsimony is now my middle name.

 

[Phorize]

Hi guys, Once again, im praying to the audio Gods for their guidance!

I have a pair of Denon 4400a monoblock amplifiers (20ish years old). They have both had new Mundorf power capacitors (The largest capacitors). I wanted to replace the smaller audio capacitors myself as I wanted to learn how to do something and get a real sence of achieving something whilst improoving the sound quality.
I have already purchased decent solder/soldering tools and im about to pull the trigger on some new caps.
My question is, can I replace all the caps with capacitors from one company line e.g: replace all the audio capacitors with Elma Silmic 2 capacitors or is that a big no no?
(I have noticed from the amp scematic that 2 capacitors are bi-polar which are not manufactured in the Silmic 2 line, but Elna do manufacture audio grade bipolar caps which I can use).
I have seen in other forums that other people use different capacitors on different places of the PCB for example in the analog signal path/DC bypass-Im not really sure what those terms mean and I wouldnt know how to identify these areas on my amplifier without guidance.

This is a list of all the electrolitic capacitors that I need to buy for each amp:

Electrolytic:

2544258785 (Aluminium +-20%) 470uf/35v electrolytic

2544260935 (Aluminium +-20%) .47uf/50v electrolytic

2544256949(Aluminium +-20%) 100uf/25v electrolytic

2544256936 (Aluminium +-20%) 47uf/25v electrolytic

2544254925 (Aluminium +-20%) 33uf/16v electrolytic x2

2544250929 (Aluminium +-20%) 100uf/6.3v electrolytic

2544260948 (Aluminium +-20%) 1uf/50v electrolytic

2544263990 (Aluminium) 22uf/100v Electrolytic

2544263084 (Aluminium) 10uf/100v eleytrolytic x4

2544260980 (Aluminium) 10uf/50v electrolytic x10

Bipolor electrolytic:

2543056959 (Aluminium Bi polar +-20%) 10uf/50v SME electrolytic bipolar

2543046901 (Aluminium Bi polar +-20%) 1uf/100v electrolytic bipolar x2
https://www.hificollective.co.uk/catalog/-c-61_68_442.html


Denon 4400a service manual link: https://www.hifiengine.com/manual_library/denon/poa-4400.shtml

Many Thanks,
Charles.

in key with other replies:

1) these amplifiers are both interesting and not run of the mill-I totally get why you want to show them some tlc and use them. Consider asking a proper technician to test them and fix diagnosed problems-many technicians are happy to share a bit of knowledge in doing this. One thing to realise it that it’s easy to cock up the tracks on an old pcb with less that a very high standard of soldering-this isn’t like soldering pipes in the bathroom.

2) if you want to get some experience tinkering, consider doing something like a simple diy headphone or preamp. These are often designed with novices in mind, have support available, use parts that are cheap, known to operate at spec, and are easily replaced when you bugger things up-which you will if you are anything like me or 99% of well meaning tinkerers. You are also unlikely to burn the house down with these sorts of things.
3) if you are determined to test and restore on old amp, there are plenty of well documented ones with entire cottage industries around them for spares etc, such as the old quads (303, 405s etc).

 

[Cbdb2]

Please no: For a hobby type project of this scale, the cost of genuine Elna Silmic, Nichicon Muse or other audiophile-annointed product purchased from the reputable sources like Digikey, Mouser or Newark/Farnell is minor compared to the labor needed to install them.

Do you know what makes "audio" caps different than regular caps? Marketing and extra cost. Do they make "accelerator" caps for CERN or "space" caps for NASA telescopes? Ever look inside any expensive pro recording mixers/gear? Not a "audio" component anywhere. Only in cosumer audio do you get these so called specialized components. Smoke and mirrors.

 

[Cbdb2]

Easy relay check. After turning it on Just short the relay contacts with a wire that you think is the problem. No soldering iron necessary.

 

[JeffS7444]

Do you know what makes "audio" caps different than regular caps? Marketing and extra cost. Do they make "accelerator" caps for CERN or "space" caps for NASA telescopes? Ever look inside any expensive pro recording mixers/gear? Not a "audio" component anywhere. Only in cosumer audio do you get these so called specialized components. Smoke and mirrors.

Oh, I'm well aware that before they "simplified" the datasheets, there were no measured parameters of anyone's audiophile electrolytic capacitors to suggest how they might actually be different , only that they were made with unusual materials including ceramic, graphite, bamboo, silk, etc. And the outer wrappings often look nicer than usual.