Renders taking 2 - 3x real-time length

All of my audio montages, that have 5-10 stereo tracks and plug-in chains on each track, are taking hours to render: so for example if the montage is 30 minutes long, it might take a couple of hours to render !! CPU use is very low whilst rendering so I dont know what’s going on, but every montage I have is the same.

Am I doing something wrong ?

Also, it’s disappointing that the render doesn’t run in the background - there’s a big ‘Generating Audio File’ dialog box so I can’t use Wavelab for other things whilst the render is happening. As it is, WL is taking hours to render montages and I can’t do anything during that time so the whole thing is really inefficient.

Do you use any UAD? UAD is slow to render offline with any DAW.

I think more plugin info would be needed to be more helpful. Some plugins like DMG have some CPU intense options within the plugin which can cause slow offline renders.

Do you have a chance to try and replicate a similar signal chain in another DAW?

If you use no plugins, are render speeds fast/normal?

there’s a big ‘Generating Audio File’ dialog box so I can’t use Wavelab for other things whilst the render is happening

Maybe you are doing the wrong operation. There should be no such box when you render. Please make a screen shot of it, so that I get a more accurate idea.


Here’s what I see when I’m rendering an Audio Momtage.

I’d have to try it again, but I think you might be processing all tracks, even if empty, while each clip is being rendered if you do it this way. That’s maybe depending on what plugins are being used too (UAD? as Justin said, although I think UAD behavior has been optimized in Wavelab now). With 9 plugins per track that could be a lot of plugins. I haven’t tried it this way in a long time, so I could be wrong about this, but that could be an issue. That and rendering to MP3, which would add a relatively minor amount of time to the renders I would hope.

I think that’s what’s going on Richard. Testing it with 5 tracks loaded with Steinberg plugins and the built in Voxengo EQ as Track FX. 4 Tracks empty. 1 track with 3 clips. At 192K to make it worse. Select all 3 clips, and Render Selected Clips to MP3. Took 19 minutes.

Then I removed the 4 empty tracks loaded with Track plugins and did the same thing to MP3. Took 5 minutes.

You might want to try clip plugins instead of track plugins. You can “select-all” the track plugins and copy and paste them into the clip plugin areas. Or you can save the track plugin chains and load them into the clips. Then remove the plugins from the tracks.

Actually with Render Selected Clips to WAV, I’m getting the same lockout dialog. I’ve never seen that before, but then I never render selected clips. I almost always render Regions / CD Tracks, which doesn’t prevent you from doing other things during the render.

My remarks about UAD are not related to the recent change in WaveLab 9 for dynamic processing. Dynamic processing helps when using clip plugins for example, because the UAD DSP is only taxed when that clip is being playing or rendered.

My comment about UAD applies to any DAW. The offline processing of UAD-2 is slow compared to most modern computers. Unless you have an ancient computer, if you take the same plugin and load the native version from Plugin Alliance or Sonnox for example, and compare the UAD version to the native version, you’ll see that the native version processes much faster than UAD.

Vertigo VSM-3 is a good example. The Plugin Alliance version is the same coding as the UAD, but the UAD version takes much longer to process.

I do believe it to be true that clip plugins when properly used can take less time to render than track or master plugins in a montage.

A DDP render is another kind of render where you are not able to do anything else during the render which I’ve always found interesting.

Good to know about UAD Justin. I don’t have any of the others to tell, but I should check them out.

I don’t have a speed problem with track or master fx in general, but in Richard’s case, rendering all selected clips on multiple tracks with only Track FX, it makes a huge difference because all of the additive Tracks FX’s in the montage are affecting the speed of each of the clip renders. I thought this might have been optimized at sometime in the past, but it seems not. The only way to get optimum speed in Richard’s existing montage is to Solo each track, select only the clips on that track and do a separate All Selected Clips render for each track.

That’s why I suggested moving all the Track plugins over to the Clips, so the clip renders won’t be affected by unnecessary processing. The only tradeoff or limit is the extra plugin instances needed for the clips. I haven’t found that to be a problem for a long time.

I did the test with 5 Tracks with Track FX, where the optimized result was 4 times faster. If you have 10 tracks the result should be about 8 times faster. That’s a big difference.

I know of one program that seems to have optimized the clips with track fx situation that Richard is facing. There might be more, really not sure.

I just tried this and although there was a minute or so wait after hitting render, when the render dialog box appears (and I’m still not even clear why it does that) it took 5 seconds to render a 2+ minute WAV to MP3. The same file takes 90 seconds if I render All Selected Clips across the montage !

I don’t believe there is any speed issue with the plugins (mostly Plugin Alliance and no UAD’s at all). So I can only hope that PG can optimise this in WL at some point.

Unfortunately using Clip plugins is not going to work for me. I’m mastering production music albums, where each track contains different length versions of the same track, so need the same plugin chain. Would be a real pain to use Clip FX rather than Track.

Unless I’m missing something, I see a 13 min montage getting rendered in 55 seconds.

You’re missing something ! That is for the clip not the montage.

Richard, I hope that PG puts in a modification to this. I can’t imagine having to render Selected Clips at speeds 5 to 10 to 15 times slower than they should be, dependent on the number of Tracks with FX and the total processing of all Track FX. That’s a crazy difference. And the lockout from the Generating Audio File dialog while rendering Selected Clips makes it a double whammy. If that can be removed it really should be. I’ve never seen that dialog when rendering Whole Montage, Regions Tracks, or even Time Selection, I don’t think.

I like the idea and flexibility of being able to do it the way you’re doing it, with Selected Clips and Track FX, but it would be totally impractical for me until an optimization was put in.

Do you know if UAD hardware is going to get any faster?

No speed issue here. Did you try, without plugins?


I certainly hope so. Some people including myself have been vocal about it on the UAD forum. Some people think I mean that I want more UAD processing power for more plugins. I clearly understand the instance limitation, but the issue here is the offline render speed of UAD in any DAW.

I good test is to make a 192k session and do a test render using a plugin that exists natively and on UAD. This includes some Sonnox, Brainworx/Plugin Alliance, and a few others.

I did some tests using the Vertigo VSM-3 and even though it’s the same plugin, the UAD versions renders much more slowly. Unless you have a super ancient and slow computer, the native versions will likely render much faster.

I hope that someday they make UAD-3 that does faster offline processing compatible to a standard modern CPU.

On a base level it’s not a huge deal, but with a longer project it can be an inconvenience and it multiplies quickly as you add a few UAD plugins, especially as track or master FX. For Clip FX, some DAWs including WaveLab are now optimized to only use the DSP for the needed clips but still, it’s slower than modern native CPU.

PG, The problem can probably best be illustrated by comparing the time to render an album All Selected Clips, when the two different examples use Track FX vs Clip FX, say in a stairstep pattern montage of 10 Tracks with one Clip on each track, and plugin chains of maybe 8-10 plugins set for moderate to extreme processing. If the montage is higher rate like 48K or 96K, and the plugins are big, heavy, and slow in the first place, the results will seem more dramatic too.

When Track FX is used, each clip seems to be processing across All Track FX in the montage during render, so the render can take 9 times longer than it should. If the same Track FX chains are moved over to the clips and removed from Track FX, the render can take up to 9 times shorter, like it should. This is when selecting all clips in the montage and rendering All Selected Clips.

I’ll make example montages.

I don’t know how Cubase and Pro Tools handle this, or maybe they don’t have a comparable All Selected Clips on multiple tracks render function? I hope somebody here knows how they handle it, because it would be horribly inefficient, and probably “fixed” long ago.

I know of one program that has apparently optimized for this specific issue of clips with track fx, or it was always that way, apparently by not processing each clip across all tracks.

@bob99: good analysis. I will change this in next (big) update, so that “render selected clips” is free from plugin processing in other tracks.


Thanks PG. Would it be possible to get rid of the Generating Audio File dialog when rendering All Selected Clips too? I don’t think any of the other renders have it.

Sometime, yes. But the speed up will be done before.