KLH 6200

First check is with a DVM. Check DC voltage of speaker terminal versus speaker return. That voltage >.03 v on either channel, unacceptable. Voltage >1 v, your output transistor probably blew. If burnt resistor is near the output transistors, extremely likely they are blown.
Possible causes are too much dirt on the heat sink, or failed output transistor insulator, or short in speaker wiring or shorted turn in driver inside the speaker.
Blown output transistors are extremely common in traveling band amps. Less common in home receivers.
Possible source of schematics are eserviceinfo.com and electrotanya.com
The listing that comes up first on search engines is usually a pay site. You often can do better by scanning further down.
It is possible to fix most amps with a soldering iron, pliers & cutters, safety glasses, screwdrivers, DVM, alligator clip leads. Some problems require a $30 analog DVM with 2 vac & 20 vac scale. Oscilloscope not required.
 
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