I'm looking to make 4 diy amps for a 3 way active xover, for bass I have Erno Borbely 75W RMS Class A power amps, for the mids & highs amps I want also Class A but without negative feedback gain X20, if possible pcb available GB or diyAudio Store.
I agree with cobjulia.
Fortunately you need 8 pcs. for 4 amps, which brings costs down to USD 12,-/pair.
With 8 pcs. you have also the chance for some matching.
Matched power devices I would order from h_a, member of this forum.