Advanced Class AB amplifier

-Class of operation - Currently class B. Variable through the 90ohm resistor. Could be set to B,AB and maybe even A with an extra pair or two of output transistors. - Output Power - 66W/4ohm - Drawn Power - 200W - Efficiency - 33% - Frequency response - 7Hz - 20Khz. Low end controlled by the 4.7mF cap and high end by 1nF cap. - THD - 0.03%@1Khz@66W. Noise from zero point switching is higher than harmonic distortion and contributes to 90% of the THD reading. To bring the THD even lower try switching deeper into class AB mode or switching to class A mode altogether. - Supply Ripple rejection - -80dB ⚠ Stick to the ground placement presented here to avoid ground loops. ⚠ Power supply tips - Filtering cap minimum 4.7mF recommended 15mF. Transformer should be rated 280VA with a secondary winding corresponding to 50V~55V.

published 11 years ago