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Displaying Photos for the Repair of a Myst G Ohm

In for repair - a little Pre-Amp, 2 Mono Blocks and Power Supply Module known as the Myst G-Ohm.
Not many of these made -- the Mono Blocks are serial numbers 0039 and 0040!
One channel blown up (No: 0040) - sure enough - in one of the Mono Blocks - Hitachi early FETs with 'emitter' resistors burnt out and driver transistors suitably blown up too.
Searching thru the Internet - no joy - the output devices are long gone from manufacture - no equivelents either.
On testing the rest of the modules - they work OK and no Cap replacements needed.
A quick call to the owner - he says - can you install some of your 405 Clone boards I've heard so much about!
A bit of a squeeze - Loudspeaker protection board, 15V voltage dropper circuit controlling the whoping 50V - 0 - 50V psu rails down to the 15VDC I need and a sacrificial set of mono blocks are converted into Quad 405 Mono Blocks with over 100 Watts RMS per channel.
Happy days.

Customer Reactions:
The Myst 405 is really good, has much better bass than the original and top end is detailed but not over bright and aggressive as the original could be with the wrong cd's and I think the longer I use it the better it gets.... well pleased with it.
The Myst 405 is sounding really good now, have had it running almost continuously since I got them back. Very pleased with them, got loads of grunt too, the original power amps would occasionally run out of steam so bonus all round!

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