Hmm... I googled this one and all I found was this link:
http://www.grahamnasby.com/misc/musicjoke_orchestral-math-test.shtml I'll try Bing next time! Francis On 2 Jun 2011, at 19:51, Jeffrey S Barker wrote: > OK, I'm ready to argue against my own post. Steve Haflich is right to > question the FFT I used in Audacity. I did extend the length (8192), but > this simply pads the windowed signal. There are also various windowing > methods (I used Hanning), all of which can cause some error in the > spectrum. Looking more carefully at my numbers (not repeated here), 5 cents > difference in the lowest frequency (353 Hz) gives a difference of only 1 Hz, > certainly within the error of my measurements. Therefore I think we can > conclude that I simply played the same note 5-10 cents flat the second > time. Steve Freides is also right that the higher harmonics are all lower > for the farther note, but I don't see any systematic change other than that > the overall volume was less farther away. > > This morning I tried two other tests. First I used the synthesized pitch > from my tuner with the same experiment, measured 2 meters away and again > about 8 meters away. There were several overtones recorded in each case and > both sets give exactly the same frequencies. Next I played a middle C on an > electronic keyboard using the midi "French Horn" setting (I'm biased). I > recorded the sound in the same room, then carried the recorder to the far > end of the house, again about 8-9 meters away) and recorded the same note. > Again the frequencies are exactly the same (within measurement error). The > amplitudes are smaller for the farther recording. I'm not sure how to > interpret the relative amplitudes. Is the variation from 20-30 dB softer > for the farther recordings enough for us to sense the pitch as flatter? > > Here are the numbers: > Middle C on electronic keyboard horn setting: > > Near Far > > C4 262 Hz 7.2dB 262 Hz -10.2dB > > C5 524 Hz 0.1dB 524 Hz -36.5dB > > G5 785 Hz -24.3dB 785 Hz -43.2dB > > C6 1047 Hz -24.1dB 1047 Hz -49.0dB > > E6 1310 Hz -20.6dB 1309 Hz -46.3dB > > G6 1571 Hz -33.0 dB 1570 Hz -64.6dB > > A#6 1833 Hz -37.9dB 1833 Hz -65.2dB > > C7 2094 Hz -40.6dB 2094 Hz -68.2dB (in noise) > > > -- > Jeffrey S. Barker > Assoc. Prof. of Geophysics, Binghamton University > Faculty Master, Dickinson Community > (607) 777-2522 (Geology) (607) 777-2826 (Dickinson) > http://bingweb.binghamton.edu/~jbarker/ > _______________________________________________ > post: [email protected] > unsubscribe or set options at > https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/solohorn%40mac.com _______________________________________________ post: [email protected] unsubscribe or set options at https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/archive%40jab.org
