Important drum editing quantization tip for those of you using Reaper...

AdamWathan

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Apr 12, 2002
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I've always had trouble trying to quantize drum tracks after splitting at transients in Reaper because the "Extend item to overlap earlier item by x milliseconds" and the "Shorten earlier items if quantized items overlap by more than x milliseconds" options never seemed to behave as expected. The short of it is that very often I would experience Reaper quantizing my hits but certain automatic crossfades were placed right over my transients completely killing them and making for a lot of irritating manual fixing.

After EXTENSIVE playing around and analysis, I finally figured out the exact mechanics of how those functions operate and why it doesn't result in the behavior that you would expect at first. I'm not going to get into the details, but this is how you avoid those transient killing crossfades and have Reaper place the crossfades at the actual points you want it to (ie. as close to the beginning of each hit as it can without having the next transient being redrawn as part of the previous item)...

Split all your tracks at say the snare hits (either via dynamic split or tab to transient and manual split)
Select all items, right click>item processing>quantize
DON'T check off the "Extend starts..." box
Check off the "Shorten earlier..." box but set the value to ZERO ms

Now all your hits are quantized with no overlaps or dumb crossfades, however, you will have some gaps and also some parts where hits that were late are now shifted early so 2 items will be right next to each other with no crossfade which will cause audio glitches... This is where the cleverness occurs!

While everything is still selected, quantize AGAIN
Check off "Extend starts..." and set the value to whatever is appropriate, I usually use like 10ms, this will be the length of your crossfade
Check off "Shorten earlier..." and set it to the same value as the "Extend starts..." field

Now all the gaps will be filled in by Reaper automatically extending the start of each item backwards and adding an auto crossfade of the specified length to make sure the transition is transparent and all of the parts where two items were right next to each other with no crossfade will have a crossfade of the specified length placed immediately before the transient.

I was SO stoked when I finally got this working the way I wanted it to today, Beat Detective eat your heart out! :lol:
 
Good tips. Are you on the Reaper forums?

Yeah I've made about 6 posts bitching about how quantize doesn't work as you would expect and deleted all of them this morning after figuring out this workaround worried that they would "fix" it and I'd have to figure out a solution all over again :lol:

No one seems to have complained ever about quantize killing transients and stuff in Reaper on those forums at all and I've never had a single response to any of my concerns about it so I don't know how many people will give a shit over there about this fix but maybe I'll post it later.
 
You are my new hero. :kickass:

It won't help for the project I'm on now (which already has gtr and bass tracked to the drums) BUT this is going to be a HUGE help for pretty much everything else!!
 
Yeah I've made about 6 posts bitching about how quantize doesn't work as you would expect and deleted all of them this morning after figuring out this workaround worried that they would "fix" it and I'd have to figure out a solution all over again :lol:

No one seems to have complained ever about quantize killing transients and stuff in Reaper on those forums at all and I've never had a single response to any of my concerns about it so I don't know how many people will give a shit over there about this fix but maybe I'll post it later.

Dude - If it's a bug, or undesired results, you shoudl definitely post it up over there. I've seen pretty quick responses to bug fixes.

Cheers! :kickass:
 
Dude - If it's a bug, or undesired results, you shoudl definitely post it up over there. I've seen pretty quick responses to bug fixes.

Cheers! :kickass:

The problem lies in the fact that if 2 items are already overlapping post quantize, the "extend starts" option takes into account that overlap time when calculating how much to extend it by... So if a hit is early and it gets shifted later to the grid and the tail of that hit overlaps the next hit by 15 ms because of the quantize, telling the next hit to extend early by 10ms has no effect because Reaper sees "Oh it's already overlapping by 15ms so I don't have to add anything else since the user was only asking for 10"... This is why the crossfade stays right on the transient :/

The way that option SHOULD work is to extend the start by an ADDITIONAL x milliseconds, regardless of whether it overlaps or not already... So if there's already a 15ms overlap and you tell it to overlap by 10ms, it will now overlap by 25ms and then the "shorten earlier items" will cut out the last 15ms of that crossfade when you set that to 10ms as well, effectively placing the crossfade directly before the transient.

If the items don't overlap at all already, then it will extend the earlier item until it overlaps by x milliseconds and draw the crossfade there which is perfect.

I can't really think of any situation where you would actually want the quantize function to behave as it does now so I see no reason why not to change how the "extend starts" works...

Like I said before though, I'm concerned that if they do update it to work this way, there might be some other undesired result I'm not expecting and I'll be back to square one trying to get it to operate the way I want... At least I have a solution with the way it works now, I'm afraid to risk it not working anymore by updating the quantize function with the proper functionality...
 
Well if you explain all of that over on the forums, I'm sure they'll listen. They're often on the #reaper IRC channel too.

Reckon you could make a drum quantization video tutorial for those of us that use Reaper? It'd really help a lot of people out!
Pipelineaudio's videos are a bit outdated at this stage!
 
+1 on you making a video dude!

and also, I think you really should make a detailed post, explaining everything you need and explain the solution. A lot of things in reaper could be seriously condensed and just made a lot easier, but the quantize especially needs some more work, from what it sounds like. I haven't done any of that yet, but in time I inevitably will.

YOU could help Reaper get a quantize that kicks ass dude :)
 
With the little workaround I posted it actually kicks serious ass already... But I'm not opposed to making a video tutorial, never done it though, can you guys point me in the right direction for freeware I can use to do it? Something to record my desktop I guess and hopefully audio at the same time, if not I'll need some software that will let me add my own audio to the video generated from the desktop recorder...
 
Try CamStudio! :D
I'll happily host a high resolution video for you. Even better if you're willing to share the Reaper project with us or one project 'before' quantization so we can practice with the same tracks you're using and an 'after' project so we know what we should be achieving. I'd happily host these for Sneapsters!
BTW, I love your Slaughter of the Soul t-shirt! :D
 
Thanks for the offer but I've got 1000gb of space and something like 1000gb of bandwidth a month on my server so I can host it myself no prob. What would be cool is if anyone has some consolidated drum tracks done to a click that they can contribute? I've got one session but it might be too sloppy to really even salvage...
 
Thanks for the offer but I've got 1000gb of space and something like 1000gb of bandwidth a month on my server so I can host it myself no prob.
Cool, you're sorted there so! :D

What would be cool is if anyone has some consolidated drum tracks done to a click that they can contribute? I've got one session but it might be too sloppy to really even salvage...
Are you looking for tracks that need to be quantized?
If so, I hope someone can contribute. I'm sure Lasse, AudioGeekZine or Ermz might have a few tracks prior to being raped by Beat Detective... :)
 
Can do that too, would rather do it with some real tracks though so I'll try what I have first. Barring that, I'll probably knock something up with NSKit samples or something since the only nice realistic drum samples I have are SSD 3.0 and I doubt Slate would be very impressed with me hosting a project full of individual replaced drum tracks ready to be cut up and stolen :p:lol: