Output transformer loss compensating circuit - has load dependent output voltage attenuated to low value via damper and attenuation resistors

摘要

The transformed losses in an LF power amplifier are caused by core and coil resistance losses of the primary and secondary side of an output transformer (4) with a high output voltage. The load dependent output voltage at the output terminals (5,6) is attenuated to a low value via an earth-free, solid, symmetrical attenuation member (7) and damping resistors. The output voltage is supplied at correct phase to an inverting negative feedback input (2) via an auxiliary transformer (8) for galvanic separation from the amplifier circuit, consisting of an amplifier input (1), inverting negative feedback input, power amplifier (3), coupling capacitor (10), and a variable, assymmetrical attenuation member (9). USE/ADVANTAGE - For supply of several loudspeakers, with loss compensation in the output transformer.