Time-warping drums

[gdgross]

Hey all,

I'm curious how much time compression/expansion do you generally feel that you can get away with, in particular on multitracked real drums? I did expand an entire song to match a new tempo (excluding a decrescendo at the end) about 4bpm. I don't hear a lot of obvious difference in the sound of the kit from one tempo to the other, but I haven't really "critically" listened yet, just a quick a/b. My other concern is if I replace the kick and toms wih samples, will it mesh with the overheads in the same way it does at the original tempo?

Background is I've got a track that I've been going back and forth with tempo wise. Leaning towards the slower tempo but the drummer really wasn't feeling it there, so we opened an older session at the faster tempo and tracked it there, and it was immediately obvious that he was grooving better and feeling it more. We convinced ourselves to stick with the faster tempo, but now I'm listening to both and second guessing that decision. Tempos are 96 and 100bpm FYI, I guess that makes a 4% difference.

Thanks!
Geoff

[mesaone]

For most manipulation of real drums, I prefer beat detective. Either elastic audio isn't the best tool for it, or I'm just not very good at using EA.

[Markrosoft]

I've found that making stems before doing the expansion/compression makes a HUGE difference - especially stuff that is in stereo and could have phase issues.

I would get your drums how you want them to sound and then bounce a stereo stem. Do that for anything else that's more complex - like maybe a bass track that has a couple different mics, or a bunch of BGs recorded separately. Then make your temp change. You can get away with a lot just using elastic audio before you hear anything - and that's the most simple way... just change the tempo. But for you can also apply the same change using xform to the stems and get away with an even bigger change without artifacts. Hope that helps

[gdgross]

Hmm I've never actually used beat detective...I've always done my drum editing manually. Back when I was on logic, I often heard artifacts created when I used their version (flex time) and I ended up abandoning it altogether. Fyi I'm a realize newbie to PT, although I've used logic for years.

I'll give beat detective a try and see if I like it any better. I didn't realize it could be used for changing tempos in addition to timing repair.

[gdgross]

Originally Posted by Markrosoft

I've found that making stems before doing the expansion/compression makes a HUGE difference - especially stuff that is in stereo and could have phase issues.

I would get your drums how you want them to sound and then bounce a stereo stem. Do that for anything else that's more complex - like maybe a bass track that has a couple different mics, or a bunch of BGs recorded separately. Then make your temp change. You can get away with a lot just using elastic audio before you hear anything - and that's the most simple way... just change the tempo. But for you can also apply the same change using xform to the stems and get away with an even bigger change without artifacts. Hope that helps

Yes I definitely created individual stems first! I've got em, might as well use them!

Thanks!

[albee1952]

For changing the tempo, Elastic audio(Rhythmic setting) in TICKS mode seems to work fine within 1-15bpm. Now for correcting timing, I would never use EA on drums. since I never seem to get any "love" from Beat detective, I do it manually(thanks to Russ for the Ninja Drum editing video).

[gdgross]

Ok, I did alittle experimenting with elastic audio (first time for me, i tend to be more of a manual edit kind of guy...)

I moved the drum tracks 2 bpm slower after deleting the decresendo at the end and making all tracks tick based, and they sound pretty good. However, some of the other tracks have some strange high pitched artifacts. Quite obvious and sounds pretty bad. I hear it on at least three tracks: vocals, a synth and bass. Vocals and synth im' not concerned with, as they are just scratch tracks, but the bass might be a keeper, so I'd like to figure out what's causing that.

In the past I've used the TCE function of the trimmer tool to compress and expand audio and haven't heard these weird sounds. Although that tool has its drawbacks too; it didn't keep the drums aligned to the grid very well, whether the track was tick or sample based.

Any thoughts?

Thanks

[gdgross]

Another interesting note - I switched to rhythmic mode in the elastic audio on the bass tracks, and although it sounded stranger in a few places (I think it's grabbing transients differently or something) the high pitched squeal noise disappeared...

[mesaone]

Yeah, Rhythmic mode operates similarly to Beat Detective's Capture/Analyze/Separate/Conform/Smooth workflow. It doesn't timestretch anything per se, it effectively chops and merges. You'll get far less "chirping" (warbly, swirling artifacts associated with time stretching or heavy data compression) when using Rhythmic instead of the other modes. I don't know how well it retains phase coherence in multi-channel or multi-track drums.