This is a copy of a post I made on the PTG forum. It describes a specific method for tuning consistent treble stretch.
“Dear Ryan,
I am tuning specific octave stretch that sets treble notes to be as in tune as possible with larger intervals. This has the added benefit of “reaching” back to the temperament octave, thereby reducing cumulative error.
I use a P4 window which also allows me to recheck notes already tuned and I often find notes that have drifted. It is a highly accurate and precise method, and is not hard to do. It is also fast because corrections on the go produce more precision early on and that reduces the need for as many multiple passes.
I basically have two different stretches, I like to call them Treble Temperaments.
Let’s assume I have evaluated pure 4:2’s as the best octave size for this piano. (See HERE)
Treble Temperament based on Pure 22nds (Triple Octaves) Using F3F4 temperament octave, these can be tuned starting at F6
M3 = M10 < M17 = M6 = m6(below)
[Pure 4:2]
……..[Wide 2:1]
……………..[Pure 12th]
………………………[ Pure 22nd ]
Plus M17 = m6(below) is a pure 11th
Treble Temperament based on Pure 19ths (2 P8 + P5). This is the maximum stretch because all the intervals are wide except the 19th and the 4:2. Using F3F4 temperament octave, these can be tuned starting at C6.
M3 = M10 < M17 > M6. and M17 = m3(below)
[Pure 4:2]
……..[Wide 2:1]
…………….[Wide 12th]
……………………………..[ Pure 19th ]
These are all within M3 > M6, the P4 test. That is why I can them the P4 windows.
Tuning this way produces a consistent stretch as long as you can hear small differences in beat speeds.
(TRY THE TEST HERE).
I will tune octaves directly (not using beat rates) starting at C7 because the beat speeds are getting a little fast and weak up there. I will listen to the P12 and P22 below and make them clean, not the octave because the pure 12th and 22nd produce a wide octave that isn’t as clean. Tuning a clean octave up there produces larger intervals that “sound” narrow to me (the note actually sounds flat to me). But if you just tune clean octaves, the stretch at C6 to B6 has already been set, so any error in the top octave lays on top of the stretch already set, up to B6.
Each stretch has a specific colour in the treble.
(See pure 19ths HERE)
This is exactly how I tune every day and this method gives me the confidence to tune for any concert level situation, knowing that my tunings sound clean, especially when large chords are being played.
Let me know if you have any questions.”
