Jason,
I was <pwa data-pwa-id="pwa-5C63D069E9D5C6EB77CCDD6B8A143D12" data-pwa-rule-id="READABILITY_2522" data-pwa-category="style" data-pwa-hint="Readability may be enhanced by using: experimenting" data-pwa-suggestions="experimenting" data-pwa-dictionary-word="playing around" class="pwa-mark">playing around</pwa> with my Excel sheet today trying to figure out why the 12ths in the treble seemed to be <pwa data-pwa-id="pwa-1B66B167253B3275284A24146B398B08" data-pwa-rule-id="JJ_RB" data-pwa-category="grammar" data-pwa-hint="Should you be using the adjective here instead of the adverb?" data-pwa-suggestions="far" data-pwa-dictionary-word="further" class="pwa-mark">further</pwa> out of tune than I thought they should be. I think I may have discovered a problem with the way (we?) are constructing the graphs. It <pwa data-pwa-id="pwa-1BA9C7136AD2F841CD2C8BBE96B21814" data-pwa-rule-id="READABILITY_260" data-pwa-category="style" data-pwa-hint="Readability may be enhanced by using: is" data-pwa-suggestions="is" data-pwa-dictionary-word="has to do with" class="pwa-mark">has to do with</pwa> the dots being plotted with "cents" as the vertical scale instead of frequency. Because "cents" is a measure of the difference between two frequencies, the reference frequency matters. The way I had initially plotted it I was using as my point of reference the fundamental frequency of each note in equal temperament multiplied by the harmonic number. So if I were calculating the y offset of the 3rd harmonic of A2, my reference point would be (110 Hz)*3 = 330. This is a problem because when I calculate the offset of E4 the reference point is (329.6276 Hz)*1. So because I'm using different reference points to calculate cents, the points on the graph are <pwa data-pwa-id="pwa-3D4E07FD2CE4D7DCFC27E7D5F7F03B51" data-pwa-rule-id="READABILITY_1820" data-pwa-category="style" data-pwa-hint="Readability may be enhanced by removing this" data-pwa-suggestions="(omit)" data-pwa-dictionary-word="actually " class="pwa-mark">actually </pwa>being plotted on a different scale, and it's meaningless to draw a line between the 3rd harmonic of A2 and the 1st harmonic of E4.
To <pwa data-pwa-id="pwa-27C105F0F1495C24ABD8DD37A963C981" data-pwa-rule-id="READABILITY_1820" data-pwa-category="style" data-pwa-hint="Readability may be enhanced by removing this" data-pwa-suggestions="(omit)" data-pwa-dictionary-word="actually " class="pwa-mark">actually </pwa>do a meaningful comparison of harmonics plotted in cents we would have to use consistent reference points. In the attached graph I've done this, plotting each harmonic using the fundamental ET frequency of the nearest note as the reference. (So I used 329.6276 as the reference frequency for the third harmonic of A2
and the first harmonic of E4,
and the sixth harmonic of A1,
and the seventh harmonic of F#1, etc.) Plotting it this way makes obvious the (slightly) flat 5th harmonic and (extremely) flat 7th harmonic. But the 3:1 12ths now show up as in tune in the treble.
Notably this problem only affects harmonics that aren't multiples of two, so on the original graph the series for the 1st, 2nd, 4th, and 8th harmonics <pwa data-pwa-id="pwa-29A6088E9C5BA10F8C92E1C03D11B9F1" data-pwa-rule-id="PASSIVE_VOICE" data-pwa-category="style" data-pwa-hint="Passive verbs make your writing less direct. Try to use an active verb instead." data-pwa-suggestions="" data-pwa-dictionary-word="are plotted" class="pwa-mark">are plotted</pwa> correctly. Anyway, I'm not sure how you got your data (if you were collecting frequencies, or Verituner was spitting out cents for you) so I can't be sure, but I think this may be a problem with your graph<pwa data-pwa-id="pwa-29FF91083294A8B1D490DA1C53AC51DD" data-pwa-rule-id="READABILITY_609" data-pwa-category="style" data-pwa-hint="Readability may be enhanced by removing this" data-pwa-suggestions="(omit)" data-pwa-dictionary-word=" as well" class="pwa-mark"> as well</pwa>.
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Anthony Willey, RPT
http://willeypianotuning.comhttp://pianometer.com------------------------------
Original Message:
Sent: 07-30-2019 18:33
From: <pwa data-pwa-id="pwa-FC1A9910243DC782FA6DD3F44DF78FE2" data-pwa-rule-id="SIMPLE_SPELLING" data-pwa-category="spelling" data-pwa-hint="Incorrect named entity spelling: Jason Kanter" data-pwa-suggestions="Jason Kander" data-pwa-dictionary-word="Jason Kanter" class="pwa-mark">Jason Kanter</pwa>
Subject: Multiple Resonance
Precisely.
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<pwa data-pwa-id="pwa-A069183878D346763F3BFF20549A08EE" data-pwa-rule-id="SIMPLE_SPELLING" data-pwa-category="spelling" data-pwa-hint="Incorrect named entity spelling: Jason Kanter" data-pwa-suggestions="Jason Kander" data-pwa-dictionary-word="Jason Kanter" class="pwa-mark">Jason Kanter</pwa>
Lynnwood WA
425-830-1561
Original Message:
Sent: 07-30-2019 13:58
From: Anthony Willey
Subject: Multiple Resonance
It took me some time to understand the graphic, but I think I get it now. If I understand correctly, for a consonant tuning you want the "interval" lines traced across the graph to be <pwa data-pwa-id="pwa-E1CF3DACD9DA774B3C70CD9320A1E061" data-pwa-rule-id="READABILITY_87" data-pwa-category="style" data-pwa-hint="Readability may be enhanced by using: flat and horizontal" data-pwa-suggestions="flat and horizontal" data-pwa-dictionary-word="as flat and horizontal as possible" class="pwa-mark">as flat and horizontal as possible</pwa>, right?
I tried making a graph of my own, using just a generic tuning curve. I added some labels showing the various intervals that I think might help people understand what's going on.
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Anthony Willey, RPT
http://willeypianotuning.com
http://pianometer.com
Original Message:
Sent: 07-30-2019 09:38
From: Patrick Draine
Subject: Multiple Resonance
Jason, what were the parameters for the P12 tuning style which you based this on? "Swafford Pure 12th?"
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Patrick Draine
Billerica MA
978-663-9690
Original Message:
Sent: 07-29-2019 00:00
From: Jason Kanter
Subject: Multiple Resonance
I've been assembling data points from Verituner. Attached is one chart of the complete set of partials of a Steinway L as recorded by Verituner using a set of tuning parameters I put in to emulate a P12 tuning. The chart displays the relationships between partials 1, 2, 3, 4, 6, 8 on notes where these partials are all theoretically identical or very close, for example D4(8), G4(6), D5(4), G5(3), D6(2), D7(1).
Railsback curves don't consider the full set of partials.
Questions, comments?
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Jason Kanter
Lynnwood WA
425-830-1561
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