Themis wrote: > I say that there ARE differences. When two amplifiers have a 0,01% > diffrence of THD, it means that the sound is not the same.
No, it most clearly does not mean that. It means that the measured THD is different. Whether THD differences of 0.01% is audible is a completely separate discussion. And its not very useful to talk about two amps having 0.01% THD. The proper measurement is at a specific power level with a bandwidth. Two amps may be identical in THD measurement at 10 watts, but different at 500 watts. > So, what I say, is that when we do an ABX test, we actually measure the > probability that some (any) auditors can find this difference. If they > don't find any, the test means nothing. No, its really much simpler than that. When you do an ABX test, you record the results. You calculate the probability that this result could happen purely by random chance. The more unlikely it is that the real measurements could happen by chance, the more confident you are that there was a real difference that was detected by your subjects. This is basic statistics, you don't have to rely on gut feelings. If you find that you can't say "with confidence" that the measured values are not just chance, you may say that there is no difference, or you may decide that your test was badly structured, and you should invent a better test. -- Pat Farrell http://www.pfarrell.com/ _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
