I'd be careful buying those parts from ebay. There are a lot of fake parts and even those distributors with relatively good reputations seem to be selling questionable parts. I'd suggest buying them from mcm. I've never had any problems with any parts I purchased from them.
Hi Perry, it was one of three transistors connected in parallel. Strangely enough, when I removed this transistor the channel continued to work but with little (almost unnoticeable) distortion. I remember that when I removed outputs form other amps, there was a lot more distortion... This Diamond amp is amassing.
If an amp has 10 parallel transistors (20 total for the channel) and you remove 9 of the 10, it shouldn't change the way it sounds unless you drive it hard. Of course, it would not survive long at high power if it needed 10 and there was only one left to do all of the work.
The Diamond audio amps are supposed to be good quality amps but I haven't seen enough of them to know if they are.
It looks like they're using the same build house as ARC and Zapco.
I bought some IRFZ44 off ebay, they looked like IR but how do you know? They worked fine but its not like I fully benched the amp and they were replacing another can't-find Sanken part that was $15 each+ship from good old Sony only. I have seen 44s in cheap China amps but they looked different.
I had a little amp with 2 TO-220 per channel, one smoked and I clipped it out. It sounded really bad, like I was powering it off a 9v battery. Most of the TO-220 amps sure are cheaper for parts, at $6ea plus shipping (depending on how much stuff you order at once) some of these smaller amps are not worth fixing. I need 2sa1694 for 5.79 at MCM and I guess I'll just wait for the next order....but I don't order that often and now it will be sitting around here .
Look here. Scroll down to "Back to repair information...." then down six paragraph headings and Perry explains the naming prefixes for those in a Note there. With those types you add it to find them, the transistor # always leaves them off.