Smoked Marantz 2215B

EastPoint

Recycler
Subscriber
Hi folks. I have a Marantz 2215B that I am told let out the magic smoke. I can see one burned resistor per channel on the amp board. I am guessing that the outputs are all blown. My plan here is to fully recap/re-transistor the amp board, then rebuild the power supply board assuming it works after redoing the amp board. Any thoughts? I found the 2215B capacitor and transistor threads.
 
Same resistors that were smoked in a 2215B I repaired a while back. Outputs and new resistors fixed it, I think I did the small transistors on the amp board too.
 
Make sure the current limiting bulbs are good too, also don't test it without clamping the outputs to the heat sink or things will go south very quickly.
 
Will do. I replaced everything on the board except I forgot to order two of the outputs, so I should have this done (ideally) by the end of the week.
 
Alright, I got the last two outputs in there. Both light bulbs tested good. I brought it up slowly with a variac and dim-bulb, and it plays fine. The power supply's big resistors are both running a bit hot, and test significantly out of spec. I'm going to order those--is there anything else specific I should do?
 
The big power supply resistors will always run hot, probably explains them being out of spec. Good call on replacing them. I can't recall any other notable weak spots on a 2215B.
 
Yep, I noticed the same thing. The big power supply resistors get pretty hot and smell like hot ceramic and dust when running normally. Probly a good idea to change them out but it's not abnormal.

Watch out for the idle current trim pots, if you haven't replaced them then spray some cleaner in them and work 'em (with the power off of course). Blow them dry with some clean air and adjust the idle current with the receiver hooked up to the DBT at first. If everything stabilizes and the trimmers aren't jumpy then do a final adjustment without the DBT.
 
All done, seems happy now. Those stupid resistors test absolutely perfect out of circuit, but they did test pretty flaky while they were heating up. I had no FM stereo initially, but thanks to this thread that's fixed now. I think we're good!
 
Alright, this is still a little weird. I set both channels to 10mv bias, as per the manual. When I have signal going through it, that 10mv goes way up, the louder the music goes. I'm assuming that's normal. However, both channels sound slightly distorted the louder I go. This should be able to play cleanly fairly loud, right? It just sounds faintly distorted when it gets louder.

I redid the entire power supply and amp boards--there are zero original transistors, electrolytics, and tantalums in the amp section.

Power supply voltages seem fine except I have 36 volts coming out at J812/811/810 instead of 33.7v. Otherwise they're pretty close.
 
OK, I got it. This was weird. I replaced H703 and H704 with KSC2690AYS as per all the suggested threads, but that turned out to be the issue. When I swapped those back to the original 2SC1384S transistors, the distortion went away. Not sure what the story is here. Seems happy now.
 
Back
Top Bottom