Your response is both arrogant and ignorant.\n\nThe Hirata method is based upon noting that musical waveforms often contain transient events which are brief, and asymmetric in shape. Recognising this, Hirata devised test waveforms which are asymmetric and quasi-transient, but which have a mean (average level) of zero – i.e. no d.c. component. Waveforms of this general type are very interesting since they can probe effects whereby the linearity of an amplifier (or other audio component) is sensitive to medium-term statistical or short-term asymmetries in the waveforms. Unfortunately, as with the Belcher method, Hirata’s proposal in the above article is based upon waveforms that have some related drawbacks. For example, the Hirata waveforms were essentially a group of rectangular pulses. The resulting spectra then depend upon the sharpness of the pulse edges, etc. \n\nThe purpose of what follows is to outline some of the amplifier effects which might need to be probed to identify non-linearities which affect musical reproduction. Then go on to consider an alternative method that might provide measured results more relevant to musical performance. \n\nMeasuring well and sound well are different things. Hirata tested many amps; some tested measured poorly like the Marantz 8B but sound fantastic while some amps that measured very well sounded bad on his testing method. There are many products that measure well and sound awful.\n\nI won't get into the end user restrictions i.e rooms ect. Nobody lives and listens in an anechoic chamber.