Audio effects

[mic pool]

Still trying to work out whether the audio effects is usable in any real situation at the moment. Main issues are lag before playback, or  playback sometimes and not others. 

Even using simple apple AUs there is a long wait when selecting a cue with an audio effect, even longer if it is running e.g. Cue just started select again to adjust etc.

Disabling an effect by unticking disables the effect but the performance hit seems to remain

incorrect plugin selected for multichannel wavs i.e stereo  altiverb for 4 ch wav.

A plugin architecture that does not support stereo plugs on cue outputs is very limiting and somewhat ignores  the issue of how effects on outputs need to be used,  particularly as there are always going to be issues with loading plugins as part of cues rather than permanently attaching them to cue outputs.

–––––––––––––––––––––––––

Mic Pool
Sound and Video Designer
www.micp.tv
m...@micpool.com
07711 308549
_________________________

[Christopher Ashworth]

On May 11, 2013, at 9:02 AM, mic pool <m...@micpool.com> wrote:

> Main issues are lag before playback, or playback sometimes and not others.

Hm, what amount of lag are you hearing? Effects will of course introduce some additional delay due to the buffer/processing time inherent in processing the audio, but it sounds like you're encountering something more than that.

> Even using simple apple AUs there is a long wait when selecting a cue with an audio effect, even longer if it is running e.g. Cue just started select again to adjust etc.

Hm; haven't encountered this. Am curious if others are hearing this as well, and under what conditions.

> Disabling an effect by unticking disables the effect but the performance hit seems to remain

This is especially puzzling, as the effect is no longer part of the processing chain at that point.

I'm wondering if the delay you are hearing is not related to effects, and is something else going on.

> incorrect plugin selected for multichannel wavs i.e stereo altiverb for 4 ch wav.

Hm, which plugin is this?

> A plugin architecture that does not support stereo plugs on cue outputs is very limiting and somewhat ignores the issue of how effects on outputs need to be used, particularly as there are always going to be issues with loading plugins as part of cues rather than permanently attaching them to cue outputs.

As I mentioned, I'll be working to (re)add support for stereo effects on cue outputs.

No software ships perfect, or else it would never ship.

Thanks,
Chris

[mic pool]

I am using Altiverb as my complex test plug and multiband compressor as my apple plug

I'll send you a workspace with 2 cues and the altiverb effect disabled

as a starter set both cues playing then try to select either of the cues.

–––––––––––––––––––––––––

Mic Pool
Sound and Video Designer
www.micp.tv
m...@micpool.com
07711 308549
_________________________

--
--
Change your preferences or unsubscribe here:
http://groups.google.com/group/qlab

Follow Figure 53 on Twitter: http://twitter.com/Figure53

---
You received this message because you are subscribed to the Google Groups "QLab" group.
To unsubscribe from this group and stop receiving emails from it, send an email to qlab+uns...@googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.

[John Leonard]

I can confirm that there's definitely a problem with Altiverb and this release of QLab 3: try using another reverb and see if you get the same problems.

John

[mic pool]

This effect per cue thing seems to cause all sorts of interesting side effects

I started testing VSL MIR Pro as my complex reverb.  This started working really well and established John's Observation that altiverb doesn't play nicely.

The lag when selecting cues was no longer present.

However every time I did an edit in MIR an extra input channel was created in the MIR PRO interface. So i deleted the effect from the test cue.

Now even though the effect is not in this cue every time I edit any effect in this cue it starts the MIR PRO program editor.

On all AU pluginsr there seems to be an issue that sometimes when the editor for the effect is open the cue wont play in the cuelist

Ozone is as expected unusable but as with Altiverb still causes performance lags even when unticked. Same with Native Instruments Guitar Rig.

My conclusions are  

1) that the Apple AU FX set works well enough  but using 3rd party plug ins can cause all sorts of problems with an effect per cue method which are complex and difficult to track down and is probably best avoided. I am wondering whether it might be a sensible preference option to only offer Apple AU plugs in the audio effects tabs.

2) Effects editing windows should be closed before running cue sequences.

–––––––––––––––––––––––––

Mic Pool
Sound and Video Designer
www.micp.tv
m...@micpool.com
07711 308549
_________________________

[Christopher Ashworth]

On May 11, 2013, at 5:26 PM, mic pool <m...@micpool.com> wrote:
>
>
> On all AU pluginsr there seems to be an issue that sometimes when the editor for the effect is open the cue wont play in the cuelist

I have not encountered this at all. If you can create steps to reproduce that would help tremendously.

-C

[Christopher Ashworth]

Mic,

In parsing through your descriptions of delays caused by audio effects, we wondered if it might be as simple as using an AU that takes a long time to get set up.

Context and information that may be relevant:

• Audio effects inserted on to a cue are only loaded when the cue is loaded.

• If you leave an audio unit interface open for a cue, and then reselect that cue, QLab will attempt to rebuild and re-open all the AU interfaces that were last open when you were editing the cue.

So if you have an AU that takes a few seconds to get started, it will always take a few seconds to get started (and perhaps a long time to build its interface) if you're using it on an individual cue.

Such an AU would indeed be pretty unsuitable applied to an individual cue, and best used on cue outputs (obviously requiring us to improve cue output support so that stereo effects can be applied there).

This would also explain why the problem is worse on older computers (as reported by John) and less noticeable on newer ones.

Does this explanation seem plausible?

Best,
Chris

[mic pool]

Dear Chris

Yes that explanation is plausible but is not the whole story

I have sent you a workspace with 2 audio cues with simple apple AUs  saved with edit windows open.

These do not play consistently.

I have also tried inserting  Altiverb to a cue output

It works but if I panic the cue or the cue ends of its own accord   a greyed out triangle appears next to the cue and only reopening the workspace will ever get the cue to play again.

I'll send you the workspace. Please find attached a screenshot of the workspace after the cue has completed playing.

–––––––––––––––––––––––––

Mic Pool
Sound and Video Designer
www.micp.tv
m...@micpool.com
07711 308549
_________________________

--
--
Change your preferences or unsubscribe here:
http://groups.google.com/group/qlab

Follow Figure 53 on Twitter: http://twitter.com/Figure53

---
You received this message because you are subscribed to the Google Groups "QLab" group.
To unsubscribe from this group and stop receiving emails from it, send an email to qlab+uns...@googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.

[Chris Ashworth]

Thanks mic I'll check it out.

The gray outline of the playback triangle indicates the cue has been stopped/ended but is still playing a tail time, as defined by the audio units applied to the cue. The tail time may be computed conservatively, and so may take along time before the cue will completely stop as "guaranteed done with the effect".

It should be the cue will stop if you wait long enough, depending on the tail time reported by this reverb.

Also try double-escape to hard stop the cue, that should halt it immediately.

I'll check the case of the audio units with windows open.

(mobile)

[mic pool]

Thanks

Well that explains the problem with Altiverb Using it with a 7s reverb time Tail time triangle still there 2 minutes later. That accounts for most of the problems I was having with altiverb.

(Triangles still there5min later) Double S stops it.

Changed reverb time to 0.1s (Tin Can)

Tail triangle still present 2 mins later. That's a conservative calculation! -I don't think it will ever end!

Resetting cue list doesn't clear it.

One other thing that occurred to me. When you sort out having stereo inserts on the cue outputs to make them fully useful you need a way of controlling parameters and changing presets on these from the cuelist.

–––––––––––––––––––––––––

Mic Pool
Sound and Video Designer
www.micp.tv
m...@micpool.com
07711 308549
_________________________

[Jeremy Lee]

Doing some basic AU testing, everything seems to work as expected here.  I inserted a stereo Waves Q3 EQ on a stereo track.  No problem.  I automated the parameters with a fade cue.  No problem.  No crashes, no lagging.

Altiverb is a very complex plug-in.  I'd try using it in the device matrix rather than on a cue by cue basis.  Everytime you launch Altiverb, it scans the impulse response folder to see if there are any new impulses there. It also can phone home to see if any new impulses are available online.  Then it can take a second or two to load the IR and configure itself.  I love Altiverb, but I don't think that I can ask QLab to load an instance of it faster than ProTools, DP, and the rest of them.  In DP it also steals keyboard focus from the host- I think it's up to the individual plug-in to either pass Keystrokes or not, if the plug-in doesn't pass it, the host never gets it.

Here's a quick example of me automating an EQ in an individual cue:

[Christopher Ashworth]

On May 14, 2013, at 10:43 AM, Jeremy Lee <jerem...@jjlee.com> wrote:

The main deficiency I see here is that the meters in the plug-in are not active while audio is passing through it.

I'm hoping I can refactor how we host Audio Units to support this.  Probably won't be a "this week" change, but I'd like to see if I can do it… have some ideas for how.

-C