Is the ACD Test Representative of Real Music and Movie Program Material?
To answer this question, we have called upon our friends at THX, (namely Senior Fellow John Dahl), who have, to this date, done the most extensive and practical multi-channel real world testing of which we know. THX: We have a 5.1 logging computer that we have used to play and profile a vast variety of movie, music and game material, identifying how much power is needed in each channel, at what frequencies, and for how long. This is the only way we know that makes it possible to develop a spec and test that guarantee that the product will play any commercial program material at reference level. The test itself uses programmed bursts of energy that mimic the maximum duration peaks that a product must play. We assume a minimum impedance of 3.2 ohms with low reactance. The test is automated and tests channels singly and in groups with high level burst signals at various frequencies, groups of frequencies, for varying lengths of time. A THX amp will play any commercial program material to
