Testing amplifiers – Hi-Fi World provides the inside story

Amplifiers reached ‘perfection’ long ago, in the late 1970s when Hitachiintroduced their power MOSFET output transistors and put them into amplifiers like the HMA-7500. It measured perfectly - but the sound? Flat and boring. Amplifier sound quality and its links to measured performance tests have been controversial ever since.

Few tests correlate strongly with sound quality. Frequency response is one that does, that’s why tone controls are effective. Distortion, however, is a far more complex animal. Some smaller distortions are audible and they ‘stain’ the sound, whilst some larger distortions, notably second harmonic, are inaudible except in large quantities – and then the lightening of timbre it produces is not unpleasant.

To continue reading please click HERE.

Leave a Reply