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Hello, Last week I picked up a nice Kenwood KA-3500 40watt intergrated amplifier in pretty good shape. Upon using it a bit more, I noticed a bit of distortion at high volume, more so in the left channel. I checked the DC offset at the speaker terminals, and the L channel said 100 mV, while the R was 25 mV. I understand this isn't so good for the L channel at least, but unfortunately this amp doesn't have any DC offset adjustments. Am I right in saying that to fix this I'd have to replace the output transistors? -- On a related issue, in the service manual I found the section on BIAS adjustment, and I read online how it can affect the DC offset. So I hooked up my voltmeter to the test points, and I got 4 mV on the L, and 8 mV on the R. In the manual it says should be 40 mV.....(!). Is there something wrong here? I tried carefully adjusting them, but they only go to 30mV with the pots fully on, this doesn't seem right to me. -- I compromised at 20 mV BIAS for both channels, and now the DC offset is 50 mV for L, and 5 mV for R, which is better, less than half what they were. I'm wondering, will I damage anything doing this, should I put them back to where they were? -- The service manual is on site here. Let me know if you want me to upload an english copy of the Owner's Manual, it has a better schematic in it all on one page, easier to read. I've also included some pictures. They're not my actual unit, but mine is exactly the same, but less dusty. -- Thanks for reading this. Many thanks in advance, and have a peaceful Palm Sunday! :taps2: Bellarmine

Üdv mindenkinek! A mellékelt rajzon akad egy kis hiba,egy sör,annak aki felfedi. Jó volna kijavítani,valahogy. Szép estét!

Sziasztok! A fenti erősítő meghalt. Ami látszik, és pillanatnyilag egyértelmű, hogy egy 680nF 63V-os kondi elégett, alatta a fólia is. Valamint két db félvezető is, amit egy fekete tollal mutatok a képeken. Sajnos egyiken sincs "felségjelzés", csak gyanítom, hogy valamiféle FET lehet.Ha valaki tudna segíteni ezek kiderítésében, esetleg rajzzal, megköszönném. Üdvözlettel Attila