jazzisfaction

Can please somebody explain me the red parts in the following patcher.

I asked my teacher already 10 times and I know what delta~ and +=~ do in theory, but I don't understand why he is using the objects to change the speed in realtime.

why do I first need the difference between the actual and previous sample to change the speed with play~?

Can please somebody explain me the red parts in the following patcher.
I asked my teacher already 10 times and I know what delta~ and +=~ do in theory, but I don't understand why he is using the objects to change the speed in realtime.
why do I first need the difference between the actual and previous sample to change the speed with play~?

play-change-speed

I think I understand now....but if anyone wants to add comments, you are welcome :-)

there are numerous ways to get play~ to vary playback speed. This method is unusual (and a little heavy-handed), but I'm guessing your tutor is planning to extend the method later, in ways that I obviously can't predict (perhaps to make pitch/speed either independent or correlated?). BUT, she/he is using the delta/difference signal as a trigger source, so that pitch/speed changes don't interrupt the phasor and cause glitches; +=~ and %1~ bring that value back into the 0. - 1. range (?). Which is then re-scaled by the total ms value from info~.

Attach a couple of scope~ and number~ objects to clarify things; and when you get a definitive answer, I'd be interested to see it!

Hi
there are numerous ways to get play~ to vary playback speed. This method is unusual (and a little heavy-handed), but I'm guessing your tutor is planning to extend the method later, in ways that I obviously can't predict (perhaps to make pitch/speed either independent or correlated?). BUT, she/he is using the delta/difference signal as a trigger source,  so that pitch/speed changes don't interrupt the phasor and cause glitches; +=~ and %1~ bring that value back into the 0. - 1. range (?). Which is then re-scaled by the total ms value from info~.

But you already knew this anyway?
Attach a couple of scope~ and number~ objects to clarify things; and when you get a definitive answer, I'd be interested to see it!

delta~ gives the difference between the current value and the previous value and because it's a phasor, we get steady delta~ values of e.x. 0.1 except when the phasor goes from 1 to 0, we get a -1.

Now we choose the playback speed (with the *~ and line~ object). If we choose '1.' there, the +=~ object will rebuild axactly the same phasor~ ramp, e.x.

If we would choose for the multiplication a factor 0.5, the delta~ values are devided in 2, so we get 0.05 instead of 0.1 and the +=~ object needs twice as much time, to reach the value '1.' again, so the 'buffer has to be stretched' with a factor twice hence the playback speed is half as fast as the original speed.

The more I think about it, the more I think it's a very cool solution :-)

It's like you say:
phasor~ reads thru the buffer.
delta~ gives the difference between the current value and the previous value and because it's a phasor, we get steady delta~ values of e.x. 0.1 except when the phasor goes from 1 to 0, we get a  -1.
Now we choose the playback speed (with the *~ and line~ object). If we choose '1.' there, the +=~ object will rebuild axactly the same phasor~ ramp, e.x.
0.1 + 0.1 = 0.2
0.2 + 0.1 = 0.3
etc.
1.0 - 1.0 = 0.
and it starts again.

If we would choose for the multiplication a factor 0.5, the delta~ values are devided in 2, so we get 0.05 instead of 0.1 and the +=~ object needs twice as much time, to reach the value '1.' again, so the 'buffer has to be stretched' with a factor twice hence the playback speed is half as fast as the original speed.
That's how I see it, no?
The more I think about it, the more I think it's a very cool solution :-)

I really love these open internal dialogues. Many times I have solved a problem just by stating it on the forum! And you've explained it waaaay better than I did

Hi Peer
I really love these open internal dialogues. Many times I have solved a problem just by stating it on the forum! And you've explained it waaaay better than I did

Thanx for this comment Brendan. That gives me hope that I understood it ;-)

And yes, I have the same experience with the forum. And what also happens often: I think about sth for hours and don't find the solution, then I post it on the forum and 5 minutes after the post I find the solution myself...strange, isn't it?

Thanx for this comment Brendan. That gives me hope that I understood it ;-)
And yes, I have the same experience with the forum. And what also happens often: I think about sth for hours and don't find the solution, then I post it on the forum and 5 minutes after the post I find the solution myself...strange, isn't it?


play~ change speed