This is quite unique amonst Amiga Peripherals. It doesn't actually do a great deal, but what it does do makes quite a difference. The idea is based on the sound theory that the human ear has an uneven response across its frequency range - about 20Hz to 20 Khz in a child falling to 10Khz in later life. Sound enhancer capitalises on the fact that the Amiga and most amplifiers cannot equalise the relative loudness of these frequencies and boots them for you. The overall result is crisper sound quality.