Topic: Octave stretching. Check if you can hear it

I intentionally processed it with some effects to not make it too easy for experienced ones.
The octave stretch parameter is at minimum and at maximum for drastic effect

P.S. Octave stretching is when higher notes are more '#' and lower ones are more 'b' to make piano sound better.

https://soundcloud.com/roman-zenkov/pianoteq


In a week aI will tell wich one one stretched

Last edited by Romariozen (07-12-2021 16:21)

Re: Octave stretching. Check if you can hear it

You will tell or an AI will tell?  ... fun post btw.  ... but one week wait will be hard

Re: Octave stretching. Check if you can hear it

PS.: lol - 3 votes and all different=)

Re: Octave stretching. Check if you can hear it

The stretched one hurts my ears. In what sense does it make the piano sound better?

Last edited by axantas (08-12-2021 22:29)

Re: Octave stretching. Check if you can hear it

Stretch it like a Spinet! lol

Pianoteq 8 Standard-Chord AI - Android App (displays chords)-Kawai VPC1
Real Samick (Stencil) Parlor Grand (5'6")-Focusrite 6i6 2nd

Re: Octave stretching. Check if you can hear it

sadhö wrote:

You will tell or an AI will tell?  ... fun post btw.  ... but one week wait will be hard


The second is stretched, you can clearly hear in the first examplr and the second one difference at the highest note. Equal tempered notes are lower than just tones (natural). That higher note in the second example is objectively higher and subjectively more clear and vivid.

Re: Octave stretching. Check if you can hear it

axantas wrote:

The stretched one hurts my ears. In what sense does it make the piano sound better?

Equal tempered scale has 7th, 4th and some other intervals much lower, that leads to some high notes in the context of some wide octave piano piece interfere with the low notes. You can nevel notice and complain about that in the context of music, but as you pay attention to that by precise listening, you will hear that stretched one doesn't have those weird interferences with the bass notes.

Last edited by Romariozen (12-12-2021 13:16)

Re: Octave stretching. Check if you can hear it

Romariozen wrote:
axantas wrote:

The stretched one hurts my ears. In what sense does it make the piano sound better?

Equal tempered scale has 7th, 4th and some other intervals much lower, that leads to some high notes in the context of some wide octave piano piece interfere with the low notes. You can nevel notice and complain about that in the context of music, but as you pay attention to that by precise listening, you will hear that stretched one doesn't have those weird interferences with the bass notes.

MMmmm, equal temperament and stretching have nothing to do with each other. Equal temperament is about the relationship of the notes "inside" an octave. The stretching can happen inside or outside the octave (mostly outside) and could be applied to any temperament, e.g. just.

Where do I find a list of all posts I upvoted? :(

Re: Octave stretching. Check if you can hear it

dv wrote:
Romariozen wrote:
axantas wrote:

The stretched one hurts my ears. In what sense does it make the piano sound better?

Equal tempered scale has 7th, 4th and some other intervals much lower, that leads to some high notes in the context of some wide octave piano piece interfere with the low notes. You can nevel notice and complain about that in the context of music, but as you pay attention to that by precise listening, you will hear that stretched one doesn't have those weird interferences with the bass notes.

MMmmm, equal temperament and stretching have nothing to do with each other. Equal temperament is about the relationship of the notes "inside" an octave. The stretching can happen inside or outside the octave (mostly outside) and could be applied to any temperament, e.g. just.


Equal tempered scale implies that every note octave above is double the frequency. It doesn't end within the octave and continues to the highest note because you don't have an end for the harmonic series and hence relatively to just intonation repeating equal temperament means you are further and further from the just intervals moving higher. When you have your piano stretched, higher notes will be higher than their equal tempered siblings and closer to the natural intervals. What are you talking about?

Last edited by Romariozen (12-12-2021 19:00)

Re: Octave stretching. Check if you can hear it

Well... for an experienced piano tuner's view on stretching, see the post by jfelice88keys in this thread: https://forum.modartt.com/viewtopic.php?id=6038

Re: Octave stretching. Check if you can hear it

Romariozen wrote:
axantas wrote:

The stretched one hurts my ears. In what sense does it make the piano sound better?

Equal tempered scale has 7th, 4th and some other intervals much lower, that leads to some high notes in the context of some wide octave piano piece interfere with the low notes. You can nevel notice and complain about that in the context of music, but as you pay attention to that by precise listening, you will hear that stretched one doesn't have those weird interferences with the bass notes.

Don't get me wrong - I am absolutely thrilled by the opportunities of Pianoteq, often experimenting with different tunings and particularly the interferencing, which happens. In your example, I listened to "single" notes, and compared them with what I am expecting from that particular note. Interesting experiments. :-)
Listened to your examples again and again after my voting - starting to doubt my vote...

Last edited by axantas (12-12-2021 21:22)

Re: Octave stretching. Check if you can hear it

I got it after checking with pianoteq itself with the 2 parameters used but voted 3 out of spite for the horrible processing and choosing a piece mostly played in the middle of the piano where no stretching occurs. LMAO!

Last edited by Chopin87 (12-12-2021 21:39)
"And live to be the show and gaze o' the time."  (William Shakespeare)

Re: Octave stretching. Check if you can hear it

The "equal temperament with perfect fifth" "Cordier" is a tuning method which, by respecting the fifths, extends the octaves. Naturally compensating the inharmonicity of the strings.
It would be interesting to get this temperament from pianoteq.

Re: Octave stretching. Check if you can hear it

See https://forum.modartt.com/viewtopic.php?pid=302#p302 for Cordier's tuning scala file (note you will have to add the piano specific inharmonicity on the top of it to get fifths being really without beatings).

Re: Octave stretching. Check if you can hear it

Romariozen wrote:
dv wrote:
Romariozen wrote:

Equal tempered scale has 7th, 4th and some other intervals much lower, that leads to some high notes in the context of some wide octave piano piece interfere with the low notes. You can nevel notice and complain about that in the context of music, but as you pay attention to that by precise listening, you will hear that stretched one doesn't have those weird interferences with the bass notes.

MMmmm, equal temperament and stretching have nothing to do with each other. Equal temperament is about the relationship of the notes "inside" an octave. The stretching can happen inside or outside the octave (mostly outside) and could be applied to any temperament, e.g. just.


Equal tempered scale implies that every note octave above is double the frequency. It doesn't end within the octave and continues to the highest note because you don't have an end for the harmonic series and hence relatively to just intonation repeating equal temperament means you are further and further from the just intervals moving higher. When you have your piano stretched, higher notes will be higher than their equal tempered siblings and closer to the natural intervals. What are you talking about?

It is not true that "Equal tempered scale implies that every note octave above is double the frequency". Equal temperament, as its full name implies, it's just for the 12 tones inside the octave: 12-Tone Equal Temperament or 12-TET. You could (and should) tune an instrument with pure sinusoidal waves in the way that you say, with double frequency at higher octaves. You may do the same with a perfectly harmonic instrument, i.e. one in which each partial of each note is a perfect integer multiple of the fundamental. The piano (and some other real instruments) have inharmonicity, i.e. the higher partials of each note are not a perfect integer multiple of the fundamental. As such, octave stretching is a way to "correct" the problem that the higher partial of a lower note will produce a beat with the fundamental (or a lower partial) of another note. This applies to any tuning, even just. As such it is only marginally related with 12-TET (to correct my slightly, but only slightly, incorrect "have nothing to do with each other). Instead the octave stretching has is strictly related with the inharmonicity (which is part of the "timbre" of an instrument). That's "what I am talking about".

Where do I find a list of all posts I upvoted? :(

Re: Octave stretching. Check if you can hear it

dv wrote:
Romariozen wrote:
dv wrote:

MMmmm, equal temperament and stretching have nothing to do with each other. Equal temperament is about the relationship of the notes "inside" an octave. The stretching can happen inside or outside the octave (mostly outside) and could be applied to any temperament, e.g. just.


Equal tempered scale implies that every note octave above is double the frequency. It doesn't end within the octave and continues to the highest note because you don't have an end for the harmonic series and hence relatively to just intonation repeating equal temperament means you are further and further from the just intervals moving higher. When you have your piano stretched, higher notes will be higher than their equal tempered siblings and closer to the natural intervals. What are you talking about?



1)octave stretching is a way to "correct" the problem that the higher partial of a lower note will produce a beat with the fundamental (or a lower partial) of another note
2) It is not true that "Equal tempered scale implies that every note octave above is double the frequency". ..



What you are trying to prove  is that stretching is changing the harmonic series of one string. That's not true. Refer to wiki and to pianoteq. "In stretched tuning, two notes an octave apart, whose fundamental frequencies theoretically have an exact 2:1 ratio, are tuned slightly farther apart (a stretched octave)."
In Equal tempered scale minor second is twelfth root of two, when you raise it to the 12th power, you have a perfect doubled frequency an octave above. When you stretch your strings, the upper notes will be higher, which in turn means that relatively to the equal-tempered scale a chord played throughout the keyboard will have its notes closer to the natural overtones.

Last edited by Romariozen (16-12-2021 19:08)

Re: Octave stretching. Check if you can hear it

Romariozen wrote:

What you are trying to prove  is that stretching is changing the harmonic series of one string. That's not true. Refer to wiki and to pianoteq. "In stretched tuning, two notes an octave apart, whose fundamental frequencies theoretically have an exact 2:1 ratio, are tuned slightly farther apart (a stretched octave)."
In Equal tempered scale minor second is twelfth root of two, when you raise it to the 12th power, you have a perfect doubled frequency an octave above. When you stretch your strings, the upper notes will be higher, which in turn means that relatively to the equal-tempered scale a chord played throughout the keyboard will have its notes closer to the natural overtones.
You were fooled someday.

I am not trying to "prove" anything. I am saying how things are for acoustic pianos, because that is what I know well for experience and study. I know absolutely nothing about PTQ besides being a casual user.

In any case, I must have explained myself wrong, because you understood the exact reverse of what it is. Stretching is not changing the harmonic series of one string. It's the exact opposite: the harmonic series of one string is NOT ideal, so the upper partials are NOT integer multiples of the fundamental. Close, but not exactly integers. That is what makes octave stretching a necessity (and an automatic thing) in an acoustic piano tuning.

Where do I find a list of all posts I upvoted? :(

Re: Octave stretching. Check if you can hear it

dv wrote:
Romariozen wrote:

What you are trying to prove  is that stretching is changing the harmonic series of one string. That's not true. Refer to wiki and to pianoteq. "In stretched tuning, two notes an octave apart, whose fundamental frequencies theoretically have an exact 2:1 ratio, are tuned slightly farther apart (a stretched octave)."
In Equal tempered scale minor second is twelfth root of two, when you raise it to the 12th power, you have a perfect doubled frequency an octave above. When you stretch your strings, the upper notes will be higher, which in turn means that relatively to the equal-tempered scale a chord played throughout the keyboard will have its notes closer to the natural overtones.
You were fooled someday.

I am not trying to "prove" anything. I am saying how things are for acoustic pianos, because that is what I know well for experience and study. I know absolutely nothing about PTQ besides being a casual user.

In any case, I must have explained myself wrong, because you understood the exact reverse of what it is. Stretching is not changing the harmonic series of one string. It's the exact opposite: the harmonic series of one string is NOT ideal, so the upper partials are NOT integer multiples of the fundamental. Close, but not exactly integers. That is what makes octave stretching a necessity (and an automatic thing) in an acoustic piano tuning.

Ok, so you basically say that real wires of pianos introduce inharmonicity and make high harmonics a bit higher and stretching was meant to mitigate the interference of higher notes with the bass notes harmonics. It doesn't though mean that stretching doesn't help mitigating equal temperament issues either since equal tempered higher notes are also lower than the bass notes real overtones. I see that octave stretching as a nice solution for making equal temperament more natural and now use it more often. Saying that stretching has nothing to do with equal temperament was misleading. You basically meant (as I cna see now) the reason of appearance of this technique yet it has a lot of practical value to make equal temperament more vivid which I use that for everytime now and that's what I meant in the beginning.

Last edited by Romariozen (16-12-2021 20:07)

Re: Octave stretching. Check if you can hear it

Romariozen wrote:

Ok, so you basically say that real wires of pianos introduce inharmonicity and make high harmonics a bit higher and stretching was meant to mitigate the interference of higher notes with the bass notes harmonics.

Correct, that is what I am saying.

Romariozen wrote:

It doesn't though mean that stretching doesn't help mitigating equal temperament issues either since equal tempered higher notes are also lower than the bass notes real overtones. I see that octave stretching as a nice solution for making equal temperament more natural and now use it more often.

Well, I did not see the connection, and I still need some more time to think about this, hence the misunderstanding

Romariozen wrote:

You basically meant (as I cna see now) the reason of appearance of this technique yet it has a lot of practical value to make equal temperament more vivid which I use that for everytime now and that's what I meant in the beginning.

If you can elaborate more on what you mean by "vivid", that would help me (and perhaps others) following your idea.

Where do I find a list of all posts I upvoted? :(

Re: Octave stretching. Check if you can hear it

dv wrote:

If you can elaborate more on what you mean by "vivid", that would help me (and perhaps others) following your idea.

That's very subjective, don't force anyone to think as I do.