This is 60W MosFet Audio Amplifier circuit.High Quality, powerful unit, 90W into 4 Ohm load.Also suited as guitar or bass amplifier.The IRFP240 and IRFP9240 MosFet devices are used as the output pair.Features:

Output power:
60 Watt RMS @ 8 Ohm (1KHz sinewave) – 90W RMS @ 4 Ohm
Sensitivity:
1V RMS input for 58W output
Frequency response:
30Hz to 20KHz -1dB
Total harmonic distortion @ 1KHz:
1W 0.003% 10W 0.006% 20W 0.01% 40W 0.013% 60W 0.018%
Total harmonic distortion @10KHz:
1W 0.005% 10W 0.02% 20W 0.03% 40W 0.06% 60W 0.09%

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This is a High Quality 25 Watt MosFet Audio Amplifier.The circuit is a simple design.It no need for a preamplifier.It can be directly connected to CD players, tuners and tape recorders. Features:

Output power:
well in excess of 25 Watt RMS @ 8 Ohm (1KHz sine wave)
Sensitivity:
200mV input for 25W output
Frequency response:
30Hz to 20KHz -1dB
Total harmonic distortion @ 1KHz:
0.1W 0.014% 1W 0.006% 10W 0.006% 20W 0.007% 25W 0.01%
Total harmonic distortion @10KHz:
0.1W 0.024% 1W 0.016% 10W 0.02% 20W 0.045% 25W 0.07%

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This circuit is a High Quality but very simple Audio Amplifier unit.No need for a preamplifier.It can be directly connected to CD players, tuners and tape recorders. Requires +- 22Vdc supply. Features:

Output power:
18 Watt RMS into 8 Ohm (1KHz sine wave)
Sensitivity:
150mV input for 18W output
Frequency response:
30Hz to 20KHz -1dB
Total harmonic distortion @ 1KHz:
0.1W 0.02% 1W 0.01% 5W 0.01% 10W 0.03%
Total harmonic distortion @10KHz:
0.1W 0.04% 1W 0.05% 5W 0.06% 10W 0.15%

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