Samuel Jayaraj said:eD, the schematic you have posted is not that of the Crescendo but modified version of the Hexfet Amp. Your simulator version has a cascoded VAS and runs off higher rails.
Hi Samuel,
the schematic that I had attached is on "Elektor Electronics-UK " april/2001 issue BUT it has a few modifications :
1) the input offset circuit : idea from Hexfet
2) output mosfets: I don´t have spice models of
2SK1530/2SJ201 used on original article , so I use
IRF´s.....they works well
3) I made one VBE multiplier from BD139 because I don´t have
spice model of 2SK537 - used as vgs multiplier.
4) I changed the gate resistors from 220ohm to 22ohm. I has
increased the margin phase ( simulator ).
5) the parallel resistor with output coil I changed from 1ohm to
2,2ohm.
All of the rest is from Elektor-april/2001 issue ( it includes value of power supply ) BUT the attached version not includes others circuits from original article ( power suply , protection circuitry and offset comp.)
So, it is almost the same from elektor. Between all mods, I believe ( regarding sound quality ) only the output power mosfet ( IRFs ) will effect ( or not ! ), because the audio signal path has not changed.
regards
eD
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