X100 backengineered here

specifically - post #45

at least in my FF (even if I have set famous 50 posts per page) direct links to post are always shabby

Very nice job, I am flattered.

The X1000 actually has 80 output devices per channel,
not 16, and the input devices (IRF610)are also
cascoded to keep the dissipation down on them.
Hello to everyone.

I am trying to build myself a copy of X250.8. I hope, that it is not a problem. I am using the old published schematics from the other projects, which Nelson Pass made free on the internet, together with the specifications of the X amplifiers and pictures of the amplifiers from the net. For the moment, I believe that I managed to reproduce, to some extent, the circuit. However, I cannot understand the following: in the attached picture it looks like the 8.2k 3W resistors are the feedback resistors, but I cannot understand why they are 3W? Also, should they not be with accuracy greater that 5%?

If any one have some ideas I will be happy if he shares them.

Best Regards,


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