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From: Paul Hovnanian P.E. on 26 Mar 2010 21:03 Run the guitar through autotune? -- Paul Hovnanian mailto:Paul(a)Hovnanian.com ------------------------------------------------------------------ Yesterday upon the stair, I met a man who wasn't there. He wasn't there again today. I think he's with the CIA. -- apologies to Hughes Mearns
From: Phil Allison on 26 Mar 2010 21:03 "Bob Eld" > > Another way, much more complicated but probably a purer second harmonic is > to use single sideband RF techniques. AM modulate a carrier with the > original signal. Strip the carrier and other side band leaving only one > side > band. Re-insert a new carrier exactly 1/2 the frequency of the first > carrier > then demodulate the resultant signal. Filter as appropriate to eliminate > spurious signals. The output should be the second harmonic of the > original. ** Absolute nonsense. What is described above is the basic process of creating and receiving a SSB radio signal - but with a big error. When receiving a SSB (speech) signal, one re-inserts a carrier on the SAME frequency as the missing one - this has to be done very precisely for the recovered speech to have a normal frequency range. Any difference in the two carrier frequencies cause a corresponding frequency offset in the speech. This means the recovered speech is FREQUENCY SHIFTED compared to the original - a process entirely different from creating a multiplied version of the speech frequencies. ...... Phil
From: Bitrex on 27 Mar 2010 01:36 Jan Panteltje wrote: > On a sunny day (Fri, 26 Mar 2010 09:11:57 -0700) it happened Tim Wescott > <tim(a)seemywebsite.now> wrote in > <gqCdnS7j-ItCQTHWnZ2dnUVZ_oGdnZ2d(a)web-ster.com>: > >> Whatever you do will, I think, give you tremendous distortion but may >> not make the thing sound a higher tone -- I suspect that at best you'll >> take out the fundamental, but leave the odd-order harmonics. >> >> Nay-saying aside, a squaring circuit would be the first thing to try -- > > I think 'double phase rectifier on small audio transformer' needs no battery at all... > The distortion will sound like real good old analog hehe. > > > |\| > ---- ----| |--------- > )||( |/| | > f )||(________ 2f ___| > )||( | > )||( |\| | > ---- ----| |--------- > |/| > LOL That right there is basically the heart of the "Octavia" octave fuzz pedal that Hendrix used.
From: Bob Eld on 27 Mar 2010 10:24 "Phil Allison" <phil_a(a)tpg.com.au> wrote in message news:8153r7FatuU1(a)mid.individual.net... > > "Bob Eld" > > > > > Another way, much more complicated but probably a purer second harmonic is > > to use single sideband RF techniques. AM modulate a carrier with the > > original signal. Strip the carrier and other side band leaving only one > > side > > band. Re-insert a new carrier exactly 1/2 the frequency of the first > > carrier > > then demodulate the resultant signal. Filter as appropriate to eliminate > > spurious signals. The output should be the second harmonic of the > > original. > > > ** Absolute nonsense. > > What is described above is the basic process of creating and receiving a SSB > radio signal - but with a big error. > > When receiving a SSB (speech) signal, one re-inserts a carrier on the SAME > frequency as the missing one - this has to be done very precisely for the > recovered speech to have a normal frequency range. Any difference in the > two carrier frequencies cause a corresponding frequency offset in the > speech. > > This means the recovered speech is FREQUENCY SHIFTED compared to the > original - a process entirely different from creating a multiplied version > of the speech frequencies. > > ..... Phil OK, scratch that idea. So reinserting a different carrier is basically just heterodyning the side band up (or down) to a different frequency, translating it but not multiplying it. Thanks for the correction.
From: Rich Webb on 27 Mar 2010 11:56
On Fri, 26 Mar 2010 17:23:13 -0700, Ralph Barone <invalid(a)not_real.ca> wrote: >Please note that the signal out of an electric guitar may contain up to >six separate notes being played at the same time. Since the OP didn't >say otherwise, I would say that advanced DSP is his only hope without >having all sorts of weird spurious self-heterodyne signals popping up >all over the place. It certainly would be useful for the OP to take the effort to comment on the various replies and to clarify just exactly what he's looking for. Hate it when somebody asks for help and then is never heard from again. -- Rich Webb Norfolk, VA |