Hi Andy. I don't think that it would be possible to mount them on the heatsink. They're mounted in a similar way to a Quad 405.
I have stuck the 2n3773's in just to see if they work but I have a problem with one channel. I don't have a scope so I can't check for oscillations etc though. Any ideas as to whether they're suitable? They seem to have very similar specs looking at the datasheets, but then I am a bit of a noob.
the MJ15003 are nice and cheap try them out.
the BUV20 are better but expensive.
why not give meridian service a call and ask there advice on the sub of these?
i repaired one of these amps a while ago which had one set of output devices already replaced (by meridian) for the life of me i cant remember the type number they used, it may have been BDY95 not sure. i was only replacing the speaker sockets.
Not yet, I will have to try again I think. Whilst waiting for a reply I ordered four MJ21194G transistors. I got them for $15 shipping which works out at around £7.50. Not bad I thought.
In the mean time, I fitted 2n3773's but I still have no joy at getting the thing to work. How accurately can you tell a transistor is faulty by testing? I have a fairly standard multimeter and used the diode test function.
I removed all the transistors and tested them, they all seemed ok, so I put them back with the new output trannies and still read -1.2v & -2.3v offset. I'm thinking of sending it to Meridian but don't want to, as I wouldn't learn anything out of it.