Pitch 'n Time Studio Plug-In General Discussion

Talk about Pitch 'n Time Studio Plug-in.

time stretch/pitch shift targeting Impulse Repsonses ?

Krakatau 1:29 PM - 26 February, 2006
Hello !

I have an hypothetic but relevant question that concerns time-stretching/crunching/pitch-shifting ( and BTW your pitch n' time product ) related to impulse responses

Do you think that the actual quality of time-str. technologies could be accurate enough, applied to impulse responses of natural rooms and spaces, to change the suggested room size of an IR without affecting the others major acoustic aspects ( or at least, the most of them ) :

shape of the room/hall/outdoor space,etc..., wall's (or any reflecting surfaces acoustic properties ), original duration of the sample, etc...
And if it is the case at what degree would it actually work without audible artifacts

I assume that it may be a specific target, that would need specific algorythms for a highest and convincing quality on that purpose

I Apologise if i bother you with my fantasy, but as an owner of Logic pro (for instance ), it may highly interest me once i'll upgrade to 7.x and buy your LE version together, but to be honest my main interest actually is the evaluation of this idea by itself

Because i think that such a feature in upstream of an impulse responses-based plug-ins ( like space designer ) can give much more flexibility to them.
And this in many other aspects as well, ( even as a simple pitch transposition algorithm ), like to sync the IR of a delay line, tune the IR of a comb filter effect, and maybe more..

Thank in advance, in all humility, for your illuminations on this subject
Steve W 11:20 PM - 28 February, 2006
Hi there,

It would depend on the specific impulse and how much you stretch it. I think the only way to know for sure if the results are acceptable is by trying.

Josh 12:46 AM - 9 March, 2006
recording and processing at a high sample rate would be a good idea I'd think...

let us know how you get on!

Matt Connolly 3:17 AM - 22 May, 2006
I was thinking about this the other day - glad there's already a discussion about it.

I think it would work well if the Impulse Response could be separated into separate early reflection and reverberation components. Then each one could be adusted individually, and then combined back together again to create a new Impulse response.

Perhaps some clever adaptive filtering could be used to achieve this separation. I only know a little about how to use them from my small experience in forensic audio, but I'm sure they could do it.

Josh 1:17 AM - 26 May, 2006
Waves do just that in their IR 1 convolving reverb plug-in I believe: www.soundonsound.com
Matt Connolly 1:11 AM - 30 May, 2006
I've only had a little play with the IR1 - I just read some of the features about it online. Sounds pretty good, now I want to go play with it again.

In any case, PnT's ability to change the pitch might also have some neat effects of changing the timbre of a reverb. And that's different from the IR reverbs i've used. (Of course it's just an idea, and might not actually work or sound good.... but there's only one way to find out.)
Krakatau 8:04 AM - 17 June, 2006

Let me suggest here what could be a use in situation of what we were debating here, if you wish to have a glance at these 3 pre-designed I.R. :


They are to be loaded in any convolution reverb that support wave files. as it is actually, they are designed to enhance any monophonic music strictly played in C

As a simple example of related production :


A piano improvisation through one of these I.R ( "flanged" ) loaded in Space designer

My interet in this particular case would be the possibility of transposing up or down, half-step by half-step, the pitch of the IR to the desired scale

But this make me think that a dedicate high-quality algorithm of time streching/pitch shifting applied to Impulse response could be at least a solution to the main usual reproach to convolution reverb actually :

Their terrible lack of flexibilty


( Thanks for reading, just don't bother too much tough ... )