Audio Power Amplifier 60 Watt
- The resistor values are not too critical, but if 1/2W metal film resistors are used throughout, this will help to reduce noise.
- The 0.5 Ohm resistors need to be 5W wirewound types.
The input capacitor should be a polyester type. If an electrolytic is to be used, the positive end goes to the amplifier (there is about +230mV on the bases of the long tailed pair transistors).
When wiring, ensure that the feedback connection is taken from the speaker output terminal, immediately before the inductor. Any track which is carrying half-wave audio from one or the other power transistor resistors will cause distortion of the feedback signal, degrading sound quality.