Thanks for info. Greatly appreciate you quick response. if the only difference btw 370 and 3700 is the input voltage - PWM controller should be the same.
So, will look up for 370 schematics, at least it will give me some clues what could cause the explosion and what kind consequences could be.
Wondering, if any reliable source of OB2358 known to this forum? Looks like Ebay only the option. But, knowing quality of "old new stock" from China, I am quite hesitant to go that route....

Re: harman kardon avr 3700

Hello, wondering if I could ask Yankys a huge favor - check part number on chip marked as IC91 on power supply pcb. Mine exploded and I could not find any schematics for this version of power supply.
Thanks in advance.