Hi Karl & Mark,
Haven't seen you guys around for a while but some news if you are listening.
I've been trying to keep learning from the different people here and slowly started to understand that there are better choices of caps than simply shotgunning Nichicon FG's into an amp. So I slowly stocked up on some Panasonic and Wima foil caps, and a variety of Panasonic FC & UnitedChemiCon KYB elcos. And 2 more A-520s. One that is being used for WIFE's PC setup with a pair of Infinity Alpha 5s and the 2nd for a friend at work that will be used with a pair of Canton GL 260 speakers.
I just finished the 520 that will go to my friend and here are the results:
R204, C177, D109 & Jumper124 removed & area cleaned to remove old Sony glue.
Jumper124 replaced with new jumper.
R204 (3.3k carbon film)(left channel idle current/power amp) replaced with Vishay-Dale ¼w 1% metal film resistor (PN: CMF553K000FKBF). R203 right channel 3.3k resistor replaced to match left channel.
C177 & D109 cleaned & re-installed.
C175 & C176 (12000µF/56v/85°c)(Power Supply) removed/cleaned old Sony glue from the area. Caps measured (11490µF & 11430µF). Replaced with UnitedChemiCon KMH 15000µF/63v/105°c snap in caps (PN: EKMH630VSN153MA63T). Jumpers under the caps were protected from short circuit with 0.2mm high dialectric silicon foil. New mounting holes for the caps (because of 10mm lead spacing vs 12mm on the original caps) drilled with 1/16” bit (0.62”/1.6mm).
C173 & C174 (330µF/25v/85°c Rubycon)(Power Supply) replaced with United ChemiCon KYB 330µF/25v/105°c (PN: EKYB250ELL331MHB5D).
C171 (22µF/16v/85°c Matsushita)(Protection) replaced with Nichicon FG 22µF/25v/85°c (PN: UFG1V220MEM1TD).
C172 (100µF/16v/85°c Elna)(Protection) replaced with Panasonic FC 100µF/25v/105°c (FC1530022-360).
Protection relay replaced with Finder 24v relay (PN: 40.52).
C170 (100µF/16v/85°c Elna)(LED drive) replaced with Panasonic FC 100µF/25v/105°c (FC1530022-360).
C123 & C124 (1000µF/16v/85°c Elna)(EQ Amp) replaced with Nichicon FGFine Gold 1000µF/16v/85°c (PN: UFG1C102MHM1TO)(can also use Nichicon Muse KZ PN: UKZ1E102MHM).
C113, C114, C115 & C116 (100µF/16v/85°c Elna)(EQ AMP) replaced with Nichicon FG Fine Gold 100µF/25v/85°c (UFG1E101MPM).
C143 & C144 (1000µF/6.3v/85°c Rubycon)(Power Amp) replaced with Nichicon FG Fine Gold 1000µF/6.3v/85°c (PN: UFG0J102MPM1TD).
C157 & C158 (100µF/16v/85°c Elna)(Power Amp) replaced with Nichicon FG Fine Gold 100µF/25v/85°c (UFG1E101MPM).
C169 (1µF/50v/85°c )(Power Amp) replaced with Wima MKS 1µF/50v poly film cap (MKS-2-5-1).
1k Idle current trimpots replaced with Bournes sealed 1k trimpots (PN: 3386G-1-102LF).
C125 &C126 (0.22µF/50v Elna [missidentified on schematic as ceramic caps])(Loudness) replaced with Wima MKS 0.22µF/50v poly film caps (MKS-2-5 220N).
So you can see that I took your advice and bought 2 of those UCC 15000µF/63v/105°c filter caps from IT-tronics. They were somewhat tricky to install, there isn't much room to drill new mounting holes and stay inside the traces and still clear everything around them. And with the smaller lead spacing I wasn't sure if the leads would clear the jumpers underneath the caps so I cut some disks of silpad and added them under the caps as security against a possible short. I would have liked to also use a Pany FC for C171 but got dumb and forgot to order that one. But I at least used a higher voltage rated FG there.
The results are most satisfying. I just listened to the first CD through it and it sounds fantastic. I'd say better than the first one that I did, enough so that I'll probably retro-fit it with these same caps. I'm also in love with these amazing little Canton GL 260 speakers. They are really really great sounding little things with great imaging.
Cheers,
James