Steve Freides <[email protected]> wrote: Jeff, fascinating stuff, not what I would have expected, but also not a result consistent with the science of sound as I know it. How can the overtones drop in pitch and not in amplitude when you record yourself from the next room? It makes sense to me that our psycho-acoustic _perception_ could be that the pitch is lower because of the change in amplitude of the overtones - what is the explanation for the change in _frequency_ of those overtones?
The explanation is that the tools being used are not being used appropriately. I don't have much time to respond right now -- need to walk the dogs and get to a rehearsal -- but I hope to respond more fully to this issue and also Cabbage's lengthy explanation, with which I generally agree that overtones (of a steady-state instrument) will generally be accurate overtones, except that Cabbage missed (teaser!) a few side issues. Briefly, Jeff did not document the length of the fft he used, not the kind of window. It really makes a difference. With the default fft frame length of 512 samples, the 353 fundamental is represented by about only four cycles. Fft windowing could easily account for the skewed frequency identified for the fundamental. It would have less effect for the higher partials. So, the fundamental may be analyzed incorrectly by audacity, not the upper partials. _______________________________________________ post: [email protected] unsubscribe or set options at https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/archive%40jab.org
