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First One - mosFET amplifier module

I do not think he was in it for business. Nothing to earn with those prices.
Absolutely. May-I add that LC is, omho, a very fine designer. And lot of testimonies tend to prove those modules are sounding better than most HI End amps on the market.
And remember that this project had began like a DIY, and, at this time LC was sharing all schematics of his work in progress, for free. ANd the prices he offered were those of a group buy.

Apart this commercial problem, let-us see if there is some flaw in the modules that could explain those several failures.
Of course, as so many modules are working fine, As they were tested and tuned before to be sold, we can suspect first a defect in the way they were used by some of us.

My first suspicion is the cooling.
Alone, one single module require a big cooler ( 0.5°C/W).
If you mount several modules on the same cooler, you need to divide their thermal resistance by the numbers of modules mounted on it.
It don't seem to be the case as I had seen on some photos of multiple modules in the same enclosure.

One other problem is the lack of schematic. Are the modules protected with Diodes (reversed) on the output ? Is the driver (or the VAS, if no driver) equipped with protection diodes to avoid excessive voltages on the gates of the power devices ? If yes, are-them (the drivers or VAS) limited in current in case of overload ?

Lazy Cat, please, at least for your image, come back here and face the situation. Everybody can understand if, for any reason, you cannot provide the replacement modules you promised. But both on a technical and commercial point of view, again, face the situation, making-it clear and honest. You cannot, on an human point of view, let your customers waiting for nothing, it is worse than everything. (Friendly).
 
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Balanced receiver.

Hi I recommend the balanced receiver from Virtual Zero. It isolate incomming problems from destroying the too fast First one moduls. I bought mine because off problems with Holton Nxl 1200 moduls. They did not like capacitors at input and also not signal transformers at output on pre. This receiver fix thoose problems.
 
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