5.1 Output Configuration for Audio Units

[p0k3]

I work in surround sound, 5.1. I have recently upgraded to Logic Pro 8, which now supports surround channels along with mono and stereo channels. From what I understand about Audio Unit plug-ins is there is no limitation on the number of inputs and outputs. One plug-in could be mono if inserted in a mono channel, stereo if inserted in a stereo channel and surround if inserted in a surround channel. Logic has added a new feature called channel configuration to plug-ins that do not have surround outputs (only mono and stereo). This feature is fantastic for plug-ins that are not surround because it allows you to basically have anywhere from 1 to 6 (5.1) instances of the plug-in which is shown in tabs. This allows you to tweak the parameters for each channel! Currently this is not possible with most of the Smart Electronics stuff because they have surround outputs. This really doesn't make any sense because the plug-ins are not surround plug-ins, meaning they don't spin sound around in the surround field. They basically just send a mono or stereo input through and output that same signal to extra channels. So in a way this is pointless. Is there any developers here that can shedd some light on this subject? I really wish some of the great plug-ins that have been developed by the Smart crew would not support 5.1 output so I could take advantage of this new wonderful feature in logic. I realize this is new to Logic and that having 5.1 output capabilities was probably advanced when the plug-ins were developed and maybe there was a reason for it but now this is just a restriction (negative) thing.

[sophia]

Ehhh no, you have things quite wrong. It is neither "pointless" nor a "restriction" that most of our plugins support any channel configuration. It is only an advantage that only provides potential benefit. The only restriction here is in Logic's options for plugin handling (more on that below).

Having plugins be designed to handling any number of channels means that you aren't forced to having this multi-instance "multi mono" mode be the only way that you can process surround streams through them. However, nothing about a stereo- mono- and surround-capable plugin prevents it from being used in either surround configuration or multi-instance multi-mono configuration. In other words, a plugin that can configure to any number of channels can do both ways, whereas a stereo- or mono-only plugin is only able to do the multi-instance thing.

The thing with this new feature in Logic is that I'm pretty sure it was designed with the idea in mind that it was a workaround to compensate for AUs that hadn't been designed to handle any number of channels. For some AUs, this is a sensible restriction due to having algorithms that may be tied specifically to mono or stereo streams. But some other AUs are restricted in this manner for no good reason, just lazy design. At any rate, I think that the idea here in Logic is that the "multi mono" feature is not ideal, but at least it allows for non-surround-capable plugins to be used on surround channels, so it's worth providing that option. But it's not ideal because it involves synchronizing multiple instances. And in some cases, depending on the plugin, this can result in some undesirable side-effects. I think that Apple are probably imagining that most people want to use the plugin across all channels of a surround stream with the same settings, so the ideal is that you just load one plugin instance and it handles a surround stream, but for plugin's that can't do that, this is a workaround.

However, from what you're saying, it's clear that you consider there to be some benefit to the "multi mono" feature, and that you would like to be able to do that with any plugin, even if the plugin is capable of processing surround streams. This would be a feature request for Logic. There's no technical reason why Logic can't offer that same option for plugins that can process any number of audio channels. Logic could simply add another menu option when choosing to instantiate such plugins on a surround track: "5.1" and also "multi mono". I'm guessing that Apple figured that folks wouldn't see it as being potentially advantageous in some cases and considered true single-instance surround processing to always be preferable and therefore didn't consider making that an option, but it's totally up to them to make that and option, and I think you could suggest that as a feature request. The ball is in the host's court. A flexible plugin (like ours that handle any number of channels) can do it any of those ways, so it's not restricted, it's only more capable.

[p0k3]

Thanks for the clarification. I don't think you quite understand the huge benefit of being able to do multi mono with multiple instances. It is not just a workaround for plug-ins that are not surround capable, it is very clear Apple has designed this to be much more than that. It doesn't create multiple instances of a plug-in (at least visually). You have to create them. You can create any combination too, for example I want L and R to go through one instance, C to go through another and LS, RS to go through one. This opens up all kinds of surround space effects. If I just run a sound through a 5.1 plug-in (that's not really a surround plug-in) like Buffer Override for example it will process all channels with the same effect settings. In multi mono with multiple instances you could have buffer divisor set to 1 in your left speaker, buffer divisor set to 2 in the right, 4 in the rear right speaker, 8 in the Rear left, you get the point. If someone is doing surround I would think this is very desirable. Having plugins be designed to handling any number of channels are good for compressors, limiters etc, stuff you wouldn't want to have different settings on each channel (although some might).

I sure hope Logic adds the ability to configure 5.1 plug-ins to multi mono although I don't think this is going to happen because Logic only creates 5.1 plug-ins that are true 5.1, meaning they position/alter sound differently in each speaker. What would be better is to have multiple output config choices when you insert the plug-in. I've seen this with audio unit instruments but not in effects. I'm guessing this is what your referring too? Is this possible with flexable outputs? Seems like the instruments that give you a choice of outputs have specific configurations, for example mono, stereo, 5.1, 2 stereo 2 mono, 6 stereo 6 mono, etc. If outputs are flexable then wouldn't the plug-in output be linked to the channel configuration it's inserted on thus giving you no choice of output configuration? And what are the benefits of this flexable output config if the plug-in is not a surround plug-in?

On a side note, thank you for all the work youv'e done with dfx!!! Iv'e spent many hours having fun with Buffer, Geo and Transverb. I'm just bummed I can't do some crazy new 5.1 stuff with them in muli mono mode.

[sophia]

Thanks for the clarification. I don't think you quite understand the huge benefit of being able to do multi mono with multiple instances. It is not just a workaround for plug-ins that are not surround capable, it is very clear Apple has designed this to be much more than that.

No, I definitely do understand the benefit. What I'm saying is that I don't think that Apple does (or that is my guess). I'm saying that my guess is that they only saw it as a workaround, and hence didn't realize that it could be a good idea to offer it as an option for all effect plugins, even those that could also do surround with a single instance.

Your comparison with Logic's instrument handling illustrates the point exactly. There's no reason why Logic couldn't similarly offer more than one configuration option for effects on surround streams. And our effects would be able to do any of the options. It's just a matter of Apple understanding that there is benefit to adding that as a feature. It's totally in the host's (Logic, in this case) court, not the plugin's court.

I agree with you, I think it would be a useful improvement to Logic to see this change made. I'll file an enhancement request for it myself, but I'm just saying that I also think it would be good to do that yourself as well. They're certainly not going to hear you here.

[p0k3]

No, I definitely do understand the benefit. What I'm saying is that I don't think that Apple does (or that is my guess). I'm saying that my guess is that they only saw it as a workaround, and hence didn't realize that it could be a good idea to offer it as an option for all effect plugins, even those that could also do surround with a single instance.

Your comparison with Logic's instrument handling illustrates the point exactly. There's no reason why Logic couldn't similarly offer more than one configuration option for effects on surround streams. And our effects would be able to do any of the options. It's just a matter of Apple understanding that there is benefit to adding that as a feature. It's totally in the host's (Logic, in this case) court, not the plugin's court.

I agree with you, I think it would be a useful improvement to Logic to see this change made. I'll file an enhancement request for it myself, but I'm just saying that I also think it would be good to do that yourself as well. They're certainly not going to hear you here.

Thanks again for further clarification. I think you should try and take a look at this new feature in Logic (if possible) as I definitely don't agree with you that Apple saw this as a work around because they have added much more than just allowing mono, stereo plug-ins to be used on surround channels in 5.1 configuration. Also, I'm sure that there is a benefit in other hosts to have the plug-ins with flexible output configuration but I don't see any in Logic. I'll have to do some further experiments in Cubase since this whole surround thing is rather new and not that many people have jumped into it! But I think developers such as DFX should definatly get into surround because it opens up new and exciting ways to manipulate sound. That is if the developers have the time

[meister eder]

I think you should try and take a look at this new feature in Logic (if possible) as I definitely don't agree with you that Apple saw this as a work around because they have added much more than just allowing mono, stereo plug-ins to be used on surround channels in 5.1 configuration.

What Sophia is trying to explain to you is this logic (no pun intended):
If Apple had considered this as a real powerful feature (and not just a 'workaround' for their own non-surround plugins), they would have made it available not only to their proprietary plugins, but would have made it available to all AU plugins as well.
The dfx plugins already have all qualifications to make use of that feature, if only Apple made it available to AU plugins in Logic.

[p0k3]

I think you should try and take a look at this new feature in Logic (if possible) as I definitely don't agree with you that Apple saw this as a work around because they have added much more than just allowing mono, stereo plug-ins to be used on surround channels in 5.1 configuration.

What Sophia is trying to explain to you is this logic (no pun intended):
If Apple had considered this as a real powerful feature (and not just a 'workaround' for their own non-surround plugins), they would have made it available not only to their proprietary plugins, but would have made it available to all AU plugins as well.
The dfx plugins already have all qualifications to make use of that feature, if only Apple made it available to AU plugins in Logic.

This feature is available to all AU plug-ins that are mono or stereo just not ones that are set up to output 5.1!!!

It makes sense for a plug-in to be 5.1 if it has 5.1 features such as a surround panner but doesn't make sense if the plug-in does not have 5.1 features. As far as I can tell the only reason would be so you could insert the plug-in into a surround path/channel. Logic does allow this now with the multi mono feature! I personally believe that since Logic is probably the most widely used AU host it might be a good idea to develop AU's that take advantage of it's features. Right now these flexible plug-ins do not and I can't see any reason why anyone else would think that this is a good thing. If there is one I'd like to know.

[sophia]

Right now these flexible plug-ins do not and I can't see any reason why anyone else would think that this is a good thing.

You're right, it would be better if Logic would make the feature available to these plugins as well. And it is up to Logic to make the feature available. It is up to Logic to make the feature available. It is up to Logic to make the feature available. It is up to Logic to make the feature available. It is up to Logic to make the feature available. It is up to Logic to make the feature available.

[p0k3]

Right now these flexible plug-ins do not and I can't see any reason why anyone else would think that this is a good thing.

You're right, it would be better if Logic would make the feature available to these plugins as well. And it is up to Logic to make the feature available. It is up to Logic to make the feature available. It is up to Logic to make the feature available. It is up to Logic to make the feature available. It is up to Logic to make the feature available. It is up to Logic to make the feature available.

Ha,ha. Yeah I get that you think that this is Apple's problem and that may be the case but right now this is my problem and everyone elses who uses Logic in a surround way. I'm not expecting Apple to make 5.1 plug-ins that aren't really 5.1 act like multi-mono plug-ins because this is not logical for reasons I've already stated. I've asked many times for a reason as to why this configuration would be desirable and have gotten no response. I can guess that this would be good for someone who wants to use Plouge Bidule and run 10 different channels into the plug-in and then out of the plugin but that's not me. Thanks for your time and thank you if you submit a request to add this feature to Logic. I will definatly be doing that.

[meister eder]

This feature is available to all AU plug-ins that are mono or stereo just not ones that are set up to output 5.1!!!

Duh, you're right! I had not even tried AUs on the surround master channel yet...
Interesting to see that of the dfx plugins, while the others appear in 5.1 configuration, "Skidder" actually does appear in multi-mono configuration.
Again interesting to see that while most AUs appear in multi-mono configuration, Apple's own AU plugins don't.

Now I am not so sure anymore that this is somthing that Apple has to "fix". It might be a similar problem like it was with multi-output instruments like BFD, Addictive Drums, etc. which did not appear in Logic8 as multi-channel plugins. If I understood correctly, the thing was that according to the AU spec you could define if the plugin is actually multi-channel or if it is 5.1 (or both or any other configuration), and the developers had not set that definition. Some NI plugins for example offer several output configurations to choose from, while real surround instruments like Absynth appear as 5.1.
But what do I know, I'm not a programmer.

[p0k3]

This feature is available to all AU plug-ins that are mono or stereo just not ones that are set up to output 5.1!!!

Duh, you're right! I had not even tried AUs on the surround master channel yet...
Interesting to see that of the dfx plugins, while the others appear in 5.1 configuration, "Skidder" actually does appear in multi-mono configuration.
Again interesting to see that while most AUs appear in multi-mono configuration, Apple's own AU plugins don't.

Now I am not so sure anymore that this is somthing that Apple has to "fix". It might be a similar problem like it was with multi-output instruments like BFD, Addictive Drums, etc. which did not appear in Logic8 as multi-channel plugins. If I understood correctly, the thing was that according to the AU spec you could define if the plugin is actually multi-channel or if it is 5.1 (or both or any other configuration), and the developers had not set that definition. Some NI plugins for example offer several output configurations to choose from, while real surround instruments like Absynth appear as 5.1.
But what do I know, I'm not a programmer.

Yes, thank you. It is good to know that someone understands where I'm coming from. Skidder would work in multi mono because it is set up to be stereo only (i think) because of it's panning features. The other plug-in's are basically mono plug-ins (no stereo or surround panning) so any output configuration would yield the same result on all channels. I believe that Apple could come up with a solution but it seems more realistic for developers to just define different channel configurations then have the plug-in choose it's configuration based on what kind of channel its inserted in. Could you imagine Logic with a list of an infinite number of output configurations to choose from? See what I mean? The output configurations would have to be defined?

Yea Apples own AU plug-ins seems to have no defined outputs too so maybe they will change them or even better, come up with a solution. I'm not a plug-in developer nor do I work on the Logic development team so what do I know.

[sophia]

This is the last time I'm going to try repeating everything in a new way...

Ha,ha. Yeah I get that you think that this is Apple's problem and that may be the case but right now this is my problem and everyone elses who uses Logic in a surround way. I'm not expecting Apple to make 5.1 plug-ins that aren't really 5.1 act like multi-mono plug-ins because this is not logical for reasons I've already stated.

Once again: When the plugins are processing 5.1, they are "actually 5.1." They're just not doing spacialization. Most plugins don't. Two-channel effects that don't do stereo spacialization aren't "not actually stereo."

And also once again: Yes, I would expect Apple to consider adding this feature. It's useful. That's what you've been saying over and over. That's a reason to add it, right?

I've asked many times for a reason as to why this configuration would be desirable and have gotten no response.

Well I count 2 responses at this point. Here's #3. What fun...

Doing what you're asking plugin developers to do would needlessly prevent surround processing in every other scenario. That includes those who do want a single instance to control a surround stream in Logic, and also every other surround-capable AU host (off the top of my head, that includes Digital Performer, Wave Editor, AU Lab, Soundtrack Pro, Plogue Bidule). Which is a pretty stupid thing to do if really it's entirely within Logic's control (and any other host's control) to give the best of both worlds. The plugins are designed wisely.

This all said, our Destroy FX plugins are also all open source, so anyone is welcome to tinker and recompile to their heart's content.

[sophia]

Interesting to see that of the dfx plugins, while the others appear in 5.1 configuration, "Skidder" actually does appear in multi-mono configuration.

It works like this: All AUs need to explicitly state what channel configurations they support. It can be limited to one config, or it can be a list of possibilities, and the list can also include "wild cards" (i.e. a plugin can say it supports 1 input with any number of outputs, any number of inputs with any number of outputs, any number of inputs and outputs as long as they are equal, any combination of such criteria in a list, etc.). What Logic seems to base it's decision on is 1) does the plugin support 6-in / 6-out (5.1 surround channel count), and 2) does the plugin support 1-in / 1-out? If the answer is "no" to the first question and "yes" to the second, then it shows up as available in "multi mono" mode. If the answer is "yes" to the first question, then the plugin shows up only available in "5.1" mode and Logic doesn't care what the answer to the second question is, even though that could be used to determine whether the plugin could additionally be available in "multi mode" and that offer made, which would allow additional possibilities. If the plugin answers "no" to both questions, then it is excluded from the surround channel plugins list. That appears to be the formula, from what I've deduced. So it's actually quite unrelated to this:

Now I am not so sure anymore that this is somthing that Apple has to "fix". It might be a similar problem like it was with multi-output instruments like BFD, Addictive Drums, etc. which did not appear in Logic8 as multi-channel plugins. If I understood correctly, the thing was that according to the AU spec you could define if the plugin is actually multi-channel or if it is 5.1 (or both or any other configuration), and the developers had not set that definition. Some NI plugins for example offer several output configurations to choose from, while real surround instruments like Absynth appear as 5.1.

[p0k3]

This all said, our Destroy FX plugins are also all open source, so anyone is welcome to tinker and recompile to their heart's content.

Seems like this is probably the only way us Logic user's will be able to use Smart Electronix plug-ins in multi-mono. I guess it is possible Apple will fix their host to work with a select few plug-in developers but I'm not getting my hopes up. So far I have 3 sets of plug-ins that seem to be coded like this, Smart Electronix's, Apple's own built in audio units and Michael Norris plug-ins (which by the way are fantastic, check em out if you haven't already). Thanks again for the info Sophia and sorry for any confusion, it's not exactly easy to explain complex topics on a forum.

Once again: When the plugins are processing 5.1, they are "actually 5.1." They're just not doing spacialization. Most plugins don't. Two-channel effects that don't do stereo spacialization aren't "not actually stereo."

Yes, I understand this and I wasn't imply that there weren't 5.1 just that they didn't have 5.1 effects so they didn't need to be 5.1 unless you wanted to pass a 5.1 signal with spatial effects through them. which would be the same as passing 6 channels through 6 instances of the same effect in mono (i think?).