― Power supply ∙ As with most power amplifiers, the ±60 V power supply need not be regulated. Owing to the relatively high power output, the supply needs a fairly large mains transformer and corresponding smoothing capacitors—see circuit diagram below. ∙ Note that the supply shown is for a mono amplifier; a stereo outfit needs two supplies. ∙ The power supply is straightforward, but can handle a large current. Voltage 'ac'serves as drive for the power-on delay circuit. The [...].