Trying to find best practice to pitch down (and occasionally up) by few semitone a huge bank of audio files. No time-stretching just speed down and up. Seems to be easy with any DAW or editor but there is a noticeable audio degradation. All the files were recorded in 48k 24bit and I can’t go back to re-record it in bigger resolution.
If anyone has some tips I would greatly appreciate it!
Thanks!
I tend to use granular synthesis to do it. There are plenty of implementations out there (both for DAWs and standalone).
Thanks, could you please name some tools to use granular synthesis in pitch shifting? Don’t know where to look there exactly.
Some tools by Celemony at least used to be excellent in this aspect, also employing granular synthesis for pitch shifting.
And yes, Ableton’s pitch shifting algorithms are pretty good. I use them all the time for all kinds of rhythmic, tonal, and textural stuff.
Ok right there are few plugins for warping and pitch shifting but I’m actually just looking for a simple (if there is) solution for transposing audio file that doesn’t lower the resolution bandwidth of the recording (what simple pitch shifting does unfortunately).
https://www.sageaudio.com/blog/recording/how-to-pitch-shift-without-losing-quality.php
I don’t want to preserve the tempo just pitch it down few semitones and I can’t re-record the files unfortunately and it’s all about classical music recordings so any degradation is not very welcome this time.
I know re-recording it on tape and slowing down could help but I don’t have any good recorder here.
I use Adobe Audition, seems pretty good in preserving quality and you can toggle whether or not you want time shift as well as pitch. Paid though :\
I think the new Ircamlab TS2 is good for this kind of things. I haven’t tried v2 but, but v1 used to be quite goo. v2 just got released and is on sale for only 29.95 $ for one or two days more.
Ahhh great didn’t know about Ircamlab, thanks!
I wish AA was not a part of the Adobe subscription gang
It’s based on the superVP-engine which is the same as in AudioSculpt. AudioSculpt is also really great, but as far as I’ve heard there’s a new version coming (but maybe not untill a year from now). And the current one only runs in 32-bit. But that’s a really powerful tool too, and the next version is probably going to be great for spectral manipulations, pitchshifting and timestretching and all that stuff.
Just got TS2 and it seems to be what I was looking for with pitch shifting “tape mode”. Great, thanks! Will check AudioSculpt when it’s out for 64-bit.
Just downloaded TS2, thanks for the tip @AndersSkibsted 
The interface is nice and it seems to be really powerful.
It is quite powerful. And in the new version you can use VST’s as well. And the SuperVP engine is really good at these spectral manipulations.
If you’re looking for a non-granular plugin, elastique pitch or melodyne are generally considered pretty high end solutions. Obviously, the quality of the result does depend on what material you’re feeding it.
SoX has a very high quality resampling engine. If I care about quality, that’s what I use. http://sox.sourceforge.net/SoX/Resampling
Thanks that looks interesting, will check!
I’m curious how you know that Celemony uses granular synthesis for pitch shifting?
Ah actually I don’t, I just assumed as much based on the sound in some examples. But as said up there, they’re apparently not. Sorry for the confusion.
In film music, dialogue, and sound effects work, the go-to plugin for transparent pitch shifting is Pitch-N-Time Pro from Serato. It’s been around for many years. It’s hideously expensive ($800), but it sounds really good. I bought it several years ago and it works very well. You should be able to get +/- 4 semitones without trouble. It has several algorithms to choose from, depending on the material and how far you want to go with it.
There is a first class way that doesn’t require an expensive plugin. It sounds as though you like the tape style pitch shifting in the new IRCAM tool. That Method, varispeed, is the easiest and best method for pitch shifting without artifacts, if it’s acceptable to have the length change at the same time as the pitch. It’s exactly like slowing or speeding up the tape you’ve recorded your sample on: sounds change pitch and duration simultaneously. There are no fft algorithms needed, and it sound great!