Brutus,
Changing the IRF510s will not fix the issues.? They can easily do good power and gain to past 6M
but the rest of the amp can't.? The last things I'd change is the IRF510s and the RD parts cost about
10X and if you lucky you might get something for the cost.
To get power out of the finals you need drive and its not there as the 3904s can't do it and
at 20m and up they have limited (and decaying with increasing frequency) gain.
This is all in the wiki.
Allison
