I bought this vintage amp 2 years ago for 60€
It worked but the source selector buttons needed maintenance/restore.
When I selected a source, one of the 2 channels was more silent than the other, some times while I was listening to music, one channel would start to disappear and I also noticed that if I turned up the volume both left and right channels would return, but in low volume there would be some noise and would loose a channel like a bad contact issue.
I figured that after 35 years of life the contacts of the buttons and the potentiometers would get dusty/oxidized and need maintenance.
So, I finally found the time during second lock down due to Covid to remove both the upper cover and the bottom cover of this thing and take a look. I also removed the front cover revealing some lights and switches.
Looks to me to be a high quality unit and everything is designed to be easily accessed and serviced.
I really like that the capacitors are safely distanced from the hot parts, compare this to modern devices where the capacitor is nearly touching the heatsink of the voltage regulator / transistor.
The phono preamp is located on an add on board and looks impressive. The green caps are Nichicon Muse audiophile capacitors of that age. I checked all the caps, some of them out of circuit and replaced 4 caps with Rubycon YXF.
I am also thinking of replacing the 2 12000uF primary caps with 2x 15000uF ones to help the amp have even better dynamic response to load.
I also cleaned the contacts of the buttons and the pots, I would like your opinion if I did a mistake. I first used CRC QD-Contact Cleaner to clean the dust/dirt/deoxidize contacts and then apllied CRC 2-26 to preserve good contact.
CRC 2-26 leaves residue where it is sprayed. Do you think this might have been wrong?
Btw I attach 10 pics before recapping the amp
It worked but the source selector buttons needed maintenance/restore.
When I selected a source, one of the 2 channels was more silent than the other, some times while I was listening to music, one channel would start to disappear and I also noticed that if I turned up the volume both left and right channels would return, but in low volume there would be some noise and would loose a channel like a bad contact issue.
I figured that after 35 years of life the contacts of the buttons and the potentiometers would get dusty/oxidized and need maintenance.
So, I finally found the time during second lock down due to Covid to remove both the upper cover and the bottom cover of this thing and take a look. I also removed the front cover revealing some lights and switches.
Looks to me to be a high quality unit and everything is designed to be easily accessed and serviced.
I really like that the capacitors are safely distanced from the hot parts, compare this to modern devices where the capacitor is nearly touching the heatsink of the voltage regulator / transistor.
The phono preamp is located on an add on board and looks impressive. The green caps are Nichicon Muse audiophile capacitors of that age. I checked all the caps, some of them out of circuit and replaced 4 caps with Rubycon YXF.
I am also thinking of replacing the 2 12000uF primary caps with 2x 15000uF ones to help the amp have even better dynamic response to load.
I also cleaned the contacts of the buttons and the pots, I would like your opinion if I did a mistake. I first used CRC QD-Contact Cleaner to clean the dust/dirt/deoxidize contacts and then apllied CRC 2-26 to preserve good contact.
CRC 2-26 leaves residue where it is sprayed. Do you think this might have been wrong?
Btw I attach 10 pics before recapping the amp
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