And now for something completely off-the-scale:
While I'm barely at the "hacker" stage in my DSP knowledge (I'm still working out how modulating a reflected mm-wavelength signal can yield accurate distance measurement over thousands of mm), I have been following the threads in this Subject-line with great interest.
I'm particularly fascinated with the complexity of obtaining a "useful" or "pleasing" tuning for a musical instrument. I hadn't realized that there were multiple "standard" ways of tuning a piano, for example. Thank you all for giving me an excuse to renew my Usenet Lurker's License.
I'd like to ask one question, though, regarding the tuning process for instruments involving mechanical vibration -- not just the ones someone referred to as "plucked" but also percussion instruments and probably others. If, as some have mentioned, the tuning of stringed instruments is made more difficult because people pluck the strings differently (is this the same as "attack". or is that a "keyboard only" term?) and the sound changes over time (decay), why not add a feedback loop into the process?
That is, why not have the "tuning instrument" induce the vibration as well as analyze the resulting sound. A PWM-speed-controlled motor with a _gentle_ off-center cam is probably not the only approach. but it doesn't seem very difficult to do (certainly no more difficult than analyzing the pure sine wave coming from a guitar string ).
Is there a reason that "tuning instruments" (at least, the ones I've seen and the ones discussed here) only analyze sounds and don't attempt to apply controlled signal stimulation? Or is it that such already exist and are simply too expensive for everyday use?
(Whoops! I think I just violated my ULL! Time to re-cloak... er, re-Lurk. )
Frank McKenney, McKenney Associates Richmond, Virginia / (804) 320-4887 Munged E-mail: frank uscore mckenney ayut minds pring dawt cahm (y'all)
-- "Very few things happen at the right time, and the rest do not happen at all. The conscientious historian will correct these defects." -- Herodotus
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