MOSFET Amplifier IRFP240/IRFP9240

Hello,

took me four 22000uF 100V capacitors and two 500VA toroidal ... really great amplifier ....
:eek::eek:
Apexaudio, in your opinion which preamp is better to combine with this amplifier?
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Yes, I am currently using one with my chip power amp. I think it sounds very good. I'm currently out of town and will post the circuit I use when I return ( on the 24th). It is dc coupled but has a cap between the output and the power amp input. So some offset ( from the source) at the input doesn't affect it.
 
Yes, I am currently using one with my chip power amp. I think it sounds very good. I'm currently out of town and will post the circuit I use when I return ( on the 24th). It is dc coupled but has a cap between the output and the power amp input. So some offset ( from the source) at the input doesn't affect it.

I'm sorry, I remember electrical schematic ...

hello
 
I used a separate supply while testing. The board is supposed to tap the +/- 36 V from the power amp. I had a hum problem with a tube stage doing that and switched to a separate supply. Didn't check the ss buffer with the power amp supplies. I've attached the circuit with supply.
 

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DAC output goes to top of Volume control.
Slider goes to Buffer input.
Pot is a dual 50 K Alps pot . You can use 10 K or 22K also. It just loads the DAC stage. As low as 10 K should be OK for a DAC. I generally prefer as high as possible. Only price you pay is poorer s/n ratio due to the higher pot resistance. If this isn't audible I don't worry about it.
Connection cables are short and so HF loss due to capacitance is very low.I get a worst case loss of about 0.4dB at 20 Khz with a total of 2 meters of cable. My cable is less than 110pF per meter though I used 150 pF to simulate the response.

Note that the higher the pot value the lower the HF roll of frequency. If you can hear a 0.5 db roll off at 20 Khz then you better use a 22K or lower pot !
 
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DAC output goes to top of Volume control.
Slider goes to Buffer input.
Pot is a dual 50 K Alps pot . You can use 10 K or 22K also. It just loads the DAC stage. As low as 10 K should be OK for a DAC. I generally prefer as high as possible. Only price you pay is poorer s/n ratio due to the higher pot resistance. If this isn't audible I don't worry about it.
Connection cables are short and so HF loss due to capacitance is very low.I get a worst case loss of about 0.4dB at 20 Khz with a total of 2 meters of cable. My cable is less than 110pF per meter though I used 150 pF to simulate the response.

Note that the higher the pot value the lower the HF roll of frequency. If you can hear a 0.5 db roll off at 20 Khz then you better use a 22K or lower pot !

thanks for your advice ..... I try to build!