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Thanks again mbz. So finally gave it a good warm up and reset bias. I set it to around 18mV warm because if played loud right before checking bias it would zip up to about 20mV. DC offset is between -35-37mv on both channels.

Finally success! Let this be a warning don't trust the markings on the ka-3500 power amp board or any board for that matter. Follow the traces and double check :) Now onto recapping the pre amp section and since I have an over supply of transistors should I just finish restoring the right...

Found it! The foil print on the bottom of the board is wrong the hole labeled B for q17 should be E it's tied directly to the base of q21. About to make the switch as soon as the solder gun warms up.

I'm at a loss checked orientation on transistors qe1-4 2sa620wn > ksa992fbu qe5,6 2sc1885 > ksc2383yta qe7,8 2sa620wb > ksa992fbu qe9,10 2sa733 > ksa733cyta qe11-14 2sc945 > ksc945cyta qe15,16 2sa733 > ksa733cyta qe17,18 2sc1735 > ksc2690ays qe19,20 2sa850 > ksa1220ays qe25, 27 2sa673 >...

Hooking up speakers just for fun get loud clean music out of the right and left channel sounds fine until half volume

Qe7 voltages 5.3, 3.1, 4.7vdc

1.3mv volume all the way up. Playing a sign wave all voltages on the schematic look good until collector q5 it's 3v dc.

There is no voltage drop across 45,47. On the working right channel I get 16mv on both. 20mv once left on for a little bit.

Just measured re27,25,23 only one out of spec was 25 at 1.5k vs 1.8k Ve1 was 40ohm to 1k ohm appears to be fine BTW the1 is 11k when I disconnected the other day

Perfect I'll start here and report back

I'm about to systematically pull inspect and replace every component in the left channel. I've even inspected diode 13 14 7 and 9 all check out with my tester. Even the transistors I pulled and replaced were all good except q17 19 21 and 23. First I just replaced 21 and 23 and that got rid of...

Weird thing is I get a clean output on the speaker terminals at 18v. Only switches that effect base of q19 and q17 is the tape rec switches.

Hav Have not tried that yet but I cannot adjust bias at all and base of q19 and q17 are up near 20v at full volume. All electrolytic caps and all transistors. And power resistors.

So it's not caps or transistors. Has to be a diode or resistor somewhere. :(

Just replaced every transistor on the left channel plus q26 and q27 and base of q19 and q17 are still not +-1.2v in fact they are in the 20v range

I know for sure qe17b and qe19b are not 1.2/-1.2. also the emitter of qe1 is not .65 like mentioned in the se I've replaced all caps with nichicon. Replaced power resistors and a few of the bigger diodes. Qe5 and 7 tested good when I pulled them

Well replaced q17 and q19 adjusted right channel to 40mv bias but no matter where I turn the pot it sits at near 0mv. I do get a clean signal out both channels according to the scope.

Sad to hear :( I'd like to hear how that Dayton 1000 turns out. I've been wanting to get the monster Dayton 18 and pair it with that amp for a couch shaking theater experience.

Little education on how pre-amp, amplifier inputs and splitters work. I have done what Roger suggested on multiple receivers one of them being a Kenwood 7300. Pre-amp takes a low level signal via phono, tape or aux and "boosts" the voltage. It also allows you to attenuate "control how loud it...

Nvm checked voltages and 50v feed was not making it through rk7. Replaced with two 1/4 watt 100k in parallel since that's all I had lying around. This amp sounds very good. In fact I don't think the klipsch have ever sounded this good with so much depth and great bass. Imaging has never...

Yeah I ended up just removing and testing every transistor on the left channel only one that was defective was 17. Some had some gain in the 140s but didn't look to see what the specs we're. Signal was clean as long as volume was below half but voltages where off after q7.

Ok I know this is old but I just spent some coin on a very very clean 7300. Plugged it in and I get nothing. It has very little dc offset 6mv or so and playing a 1khz test tone provides a nice clean sine wave out on pin 6 all the way to pin 19 on the relay board. Same thing for the other...

Yeah I don't know why offset is so high I gain matched both transistors with a gain of 371. I was reading and it looks like matching Vbe would give better results. I ordered 30 of those transistors so I'll try to bring that down later. I decided to remove one transistor at a time to test and...

For mine qe17 was bad causing the top half to be distorted. Replacing 17,18,19and 20 on page 2 of this thread http://audiokarma.org/forums/index.php?threads/distorted-audio-on-kenwood-ka-3500-need-a-recap.646890/

Qe17 is bad. Do I need to replace qe19 as well didn't notice but legs are dark and corroded on both but 19 passes. What would be a good replacement and if replacing both should they be matched?