How To Tune a Piano:
A Summary of Chapters 6 and 7 from "Piano Servicing, Tuning, and Rebuilding" by Arthur Reblitz
Part IV of V
Did you hear about Francis Augustus, the Potter with a bad temperament?
Even when he made a kil'n, he fired all his employees.
The Potter F-A Temperament:
This temperament spans a M10th, and four pivotal thirds are used to create a foundation. The three notes above the high-F are tuned in sixths rather than octaves in order to "carry the feeling of the temperament." Also, because the tuner can use the M6-M3 test to check sixths, one hand is free to remain on the tuning lever. (With octaves, the M3-M10 test is preferred and requires both hands.)
Again, notes to tune will be orange, and tuning direction will be green. Checks will be bulleted.
Even when he made a kil'n, he fired all his employees.
The Potter F-A Temperament:
This temperament spans a M10th, and four pivotal thirds are used to create a foundation. The three notes above the high-F are tuned in sixths rather than octaves in order to "carry the feeling of the temperament." Also, because the tuner can use the M6-M3 test to check sixths, one hand is free to remain on the tuning lever. (With octaves, the M3-M10 test is preferred and requires both hands.)
Again, notes to tune will be orange, and tuning direction will be green. Checks will be bulleted.
- Lift the dampers and use the temperament strip to mute the outside strings from the C below middle C to the A above middle C.
- Tune A440 to F2 with a tuning fork as in exercise 5.
- Tune low-A to A440
- low-F/low-A 3rd ≤ low-F/A440 10th.
- Tune low-F flat to low-A at about 6.9 bps.
- Tune high-F to low-F.
- C#3/low-F 3rd ≤ C#3/high-F 10th. I'll call this the M3-M10 test.
- Tune C# (above middle C) sharp to low-A at about 8.7 bps. We now have four pivotal thirds.
- low-F/low-A 3rd at about 7 bps < low-A/C# 3rd at about 9 bps < C#/high-F 3rd at about 11 bps < high-F/A440 3rd at about 14 bps.
- Tune D sharp to low-F at about 8 bps.
- low-F/low-A 3rd at about 7 bps < low-F/D 6th at about 8 bps < low-A/C# 3rd at about 9 bps.
- low-A/D 4th and D/high-A 5th should sound good.
- Tune A# flat to D at about 9.2 bps.
- low-A/C# 3rd < A#/D 3rd.
- low-F/C# 4th and low-F/C 5th should sound good.
- Tune low-F# flat to low-A# at about 7.3 bps.
- low-F#/low-A# 3rd < low-F/low-A 3rd.
- Tune D# sharp to low-F# at about 8.4 bps.
- low-F/D 6th < low-F#/D# 6th.
- low-A#/D# 4th should sound good.
- Tune B flat to D# at about 9.8 bps.
- low-A/C# 3rd < low-A#/D 3rd < B/D# 3rd.
- Tune low-G flat to B at about 7.7 bps.
- low-F/low-A 3rd < low-F#/low-A# 3rd < low-G/B 3rd.
- low-F/D 6th = low-G/B 3rd. This is called the M6-M3 test.
- Tune E sharp to low-G at about 8.9 bps.
- low-F/D 6th < low-F#/D# 6th < low-G/E 6th.
- B/E 4th and E/high-A 4th should sound good.
- Tune middle C flat to E at about 10.4 bps.
- low-F/C 5th and C/high-F 4th should sound good.
- low-A/C# 3rd < low-A#/D 3rd < B/D# 3rd < C/E 3rd.
- Tune low-G# flat to middle C at about 8.2 bps.
- low-G#/C# 4th should sound good.
- Test adjacent M3rds, M6ths, P4ths, and P5ths.
- Check all M6-M3 tests.
- Tune high-F# sharp to low-A.
- Check 3rds, 4ths, 5ths, M6-M3, and M3-M10.
- Tune high-G sharp to low-A#.
- Check 3rds, 4ths, 5ths, M6-M3, and M3-M10.
- Tune high-G# sharp to B.
- Check 3rds, 4ths, 5ths, M6-M3, and M3-M10.
And that is the end of setting the temperament. We'll conclude Part IV by covering a few basic principles on how to finish the midrange, treble and bass sections.
In the midrange, tune the center strings to the temperament by octaves up to the treble break, where the agraffes stop. Then tune the center strings down into the low part of the treble bridge. Check to make sure that ascending adjacent M10ths smoothly increase in beat rates. After this, unmute one string at a time by releasing the temperament strip from left to right, and tune the unisons. Always listen to all three strings of each trichord together, and use wedge mutes as needed.
The high treble can be muted with a narrow temperament strip or wedge mutes. Again, tune the center string of each trichord first. The high treble is more difficult, because it takes less movement from the lever to change pitch, and the tone dies more quickly. Test each pitch with adjacent M10ths, double octaves, and M17ths. Double octaves will sound flat if the high treble is not stretched enough, but if they are tuned too sharp, they will beat. Also, because the notes surrounding the treble break are often less stable, they should be rechecked after six to eight higher notes have been tuned.
The low bass strings create partials that are close to the fundamentals of higher notes on the keyboard. (The fundamental creates the unison, the second partial coincides with one octave higher, the third is an octave and a fifth, the fourth is two octaves, the fifth is two octaves and a third, and the sixth is two octaves and a fifth.) The third and higher partials will create beats, and these intervals should be compromised so that none sounds very bad. As the pitches get lower, use P5ths, M10ths, and M17ths to test beat progressions. Once those get "muddy," use M17ths only, and in the lowest octave, use two octaves plus a third and two octaves plus a fifth. A nice way to check the accuracy of bass notes is to listen to the bass note with its major chord in second inversion played above it. For example, if C is the bass note, the chord played above it would be GCE.
Only one more part to go!
In the midrange, tune the center strings to the temperament by octaves up to the treble break, where the agraffes stop. Then tune the center strings down into the low part of the treble bridge. Check to make sure that ascending adjacent M10ths smoothly increase in beat rates. After this, unmute one string at a time by releasing the temperament strip from left to right, and tune the unisons. Always listen to all three strings of each trichord together, and use wedge mutes as needed.
The high treble can be muted with a narrow temperament strip or wedge mutes. Again, tune the center string of each trichord first. The high treble is more difficult, because it takes less movement from the lever to change pitch, and the tone dies more quickly. Test each pitch with adjacent M10ths, double octaves, and M17ths. Double octaves will sound flat if the high treble is not stretched enough, but if they are tuned too sharp, they will beat. Also, because the notes surrounding the treble break are often less stable, they should be rechecked after six to eight higher notes have been tuned.
The low bass strings create partials that are close to the fundamentals of higher notes on the keyboard. (The fundamental creates the unison, the second partial coincides with one octave higher, the third is an octave and a fifth, the fourth is two octaves, the fifth is two octaves and a third, and the sixth is two octaves and a fifth.) The third and higher partials will create beats, and these intervals should be compromised so that none sounds very bad. As the pitches get lower, use P5ths, M10ths, and M17ths to test beat progressions. Once those get "muddy," use M17ths only, and in the lowest octave, use two octaves plus a third and two octaves plus a fifth. A nice way to check the accuracy of bass notes is to listen to the bass note with its major chord in second inversion played above it. For example, if C is the bass note, the chord played above it would be GCE.
Only one more part to go!
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