The AN7500FHQ is a single chip IC optimum for a 1.5 V headphone stereo system including pre-amp., power amp. and Dolby B type noise reduction circuit. Current consumption in a Dolby circuit off mode has been drastically reduced and an operating supply voltage has also been lowered to 0.98 V. Much fewer external components have been realized due to an integration of audio signal processing system into a single chip circuitry in a small outline package and space saving mounting of a set.