Results for 24bit/96KHz test Reply #50 – 2004-06-07 20:43:25 QuoteA signficant issue is that Oohashi was not able to achieve postitive results with LCS compared to baseline. However, he was able to achieve positive results whith FRS vs. HCS. THis is not logical. I can not conclude his results have any validity in this circumstance. If the high frequency content is directly exciting ANYTHING in a human, then why is it when isolated, no positive results were acheivable? What did cuase the positive results when HF was added to the high cut?This is illogical if we assume that the cause of a supposed audible difference between HCS and FCS, or to put it in simple words, low definition vs high definition, comes from an intermodulation between two neighborous ultrasonic frequencies. But this is not sure. Other experiments, like Griesinger's one ( http://world.std.com/~griesngr/intermod.ppt ) that can be easily reproduced (but can easily fry your tweeters), show that even between an audible and an inaudible frequency, no intermodulation is audible. So there may be another process at work. The most likely that I can thing of is a distorded impulse response. Distorded in a way that can't be modelized in terms of harmonic or intermodulation distortion. The ear would thus react differently to a lowpassed impulse than to a full range impulse. But it does not imply that it should react in any way to a high passed impulse.Your point is interesting, but this apparent inconsistency doesn't surprise me. Actually, all this stuff is inconsistent to begin with : we know that past a given frequency, pure tones can't be heard, and it seems proven that these frequency don't intermodulate with lower ones in our ears. Thus it would be illogical that high definition audio formats can sound any different than low definition ones (talking about sample rate only).So dismissing this result just because of this is quite the same as dismissing it just because it is successful.QuoteAddressing your comment:IF the standard 44.1khz sample rate represents human auditory range, then how can this be logical? If the original source has audible IMD componentes(I'm sure many do) as a result of inaudible and audible frequency reactions, then the audible components/modulations will still reside within the audible band. These will be recorded faithfully since the artifacts are created before recording. Maybe I did not understand you?-ChrisNo I was not talking about this at all. I considered the following argument :1-The spectrum analysis shows that musical instruments have weak high frequency content.2-Tests have showed that even strong high frequency content don't intermodulate with audible frequencyConclusion : higher sample rate can't improve audio quality.And I object that the spectrum analysis of musical instruments only show the average level of their high frequency content, while the instant level, especially in percussive instruments, during transients (=impulses) might be much higher.It should be shown using spectrograms (3D graphs with vertical = frequency, horizontal = time, color = intensity) instead of spectrum analysis (2D graph with vertical = intensity and horizontal = frequency), but there again, I wonder if changing the analyser setting (using a shorter window analysis) would not show even higher HF content.