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  #11  
Old 01-26-2022, 08:29 AM
Rich Breen Rich Breen is offline
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Default Re: Multi mono - Singal generator out of phase

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Originally Posted by oortone View Post
...In the case of Signal Generator there's no need for a stereochannel but if this phase issue exists in Trim (which is also only available as multi mono) then that's very bad.
Of course it does not. Processing will be in phase between channels in a multi-mono instantiation of most garden-variety plugs (including Trim). One should not expect plugs with any form of randomized process (delays, reverbs, modulation) to be phase locked between multi-mono instances.
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  #12  
Old 01-26-2022, 10:56 AM
MrDibS MrDibS is offline
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Default Re: Multi mono - Singal generator out of phase

If this wasn't already made clear:

A multimono instance is actually 2 instances, one on the right and one on the left.
A mono track panned center is one instance routed to left and right.

Two mono instances could very likely start generating a few samples apart from each other and therefor be out of phase at certain frequencies.

One mono instance panned center should track phase wise across the spectrum. If it doesn't you should look a the rest of your session to see if you are routing through something strange.
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  #13  
Old 01-26-2022, 11:09 AM
daeron80 daeron80 is offline
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Default Re: Multi mono - Singal generator out of phase

That's fun! The phase meter jumps all over the place. tbh, in the nearly three decades that plugin has existed, I don't think I'd ever instantiated it as multi-mono.
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  #14  
Old 01-28-2022, 09:20 AM
oortone oortone is offline
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Default Re: Multi mono - Singal generator out of phase

Quote:
Originally Posted by Rich Breen View Post
Of course it does not. Processing will be in phase between channels in a multi-mono instantiation of most garden-variety plugs (including Trim). One should not expect plugs with any form of randomized process (delays, reverbs, modulation) to be phase locked between multi-mono instances.
That depends on what you mean by phase locked. In a stereo reverb there are not the same signals in L and R but I would expect them to be in phase time wise. That is the processing result of sample Xn-left and Xn-right should be presented at the output at the same output sample position.

Actually I would expect an oscillator to be in phase too in the same way in a multi mono plugin on a modern system...
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  #15  
Old 01-28-2022, 09:22 AM
oortone oortone is offline
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Default Re: Multi mono - Singal generator out of phase

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Originally Posted by MrDibS View Post
If this wasn't already made clear:

A multimono instance is actually 2 instances, one on the right and one on the left.
A mono track panned center is one instance routed to left and right.

Two mono instances could very likely start generating a few samples apart from each other and therefor be out of phase at certain frequencies.


One mono instance panned center should track phase wise across the spectrum. If it doesn't you should look a the rest of your session to see if you are routing through something strange.
This partly contradicts Rich Breen:s answer unless you by generating only mean oscillators. If phase coherency in general is not guaranteed using Multi Mono (when Multichannel is not available) then I must repeat, I don't get what they are intended for.
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  #16  
Old 01-28-2022, 10:59 AM
midnightrambler midnightrambler is offline
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Default Re: Multi mono - Singal generator out of phase

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Originally Posted by oortone View Post
This partly contradicts Rich Breen:s answer unless you by generating only mean oscillators. If phase coherency in general is not guaranteed using Multi Mono (when Multichannel is not available) then I must repeat, I don't get what they are intended for.
I don't get why you can't just use one signal generator and route it where you need it. You wouldn't have 24 separate sine waves if you were lining up a tape machine, you'd use one and route it accordingly.
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  #17  
Old 01-28-2022, 12:26 PM
MrDibS MrDibS is offline
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Default Re: Multi mono - Singal generator out of phase

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Originally Posted by oortone View Post
This partly contradicts Rich Breen:s answer unless you by generating only mean oscillators. If phase coherency in general is not guaranteed using Multi Mono (when Multichannel is not available) then I must repeat, I don't get what they are intended for.

I’m not following what you are saying.

Yes I mean oscillators. Generator is a synonym for oscillator, hence the name of the plugin.

There is no phase coherency issue with using multi mono plugins. Two oscillators, however are not guaranteed to line up every time no matter what kind of channel they are dropped into. Rich said the exact same thing as an oscillator is microscopically randomized. Nothing I said contradicted him in the least.

Some of the brightest minds on this forum have patiently and respectfully explained to you that your test is flawed. To test phase, one must use one mono oscillator routed to both left and right. I’m not sure what’s left to discuss here.


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  #18  
Old 01-31-2022, 06:30 AM
oortone oortone is offline
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Default Re: Multi mono - Singal generator out of phase

Quote:
Originally Posted by midnightrambler View Post
I don't get why you can't just use one signal generator and route it where you need it. You wouldn't have 24 separate sine waves if you were lining up a tape machine, you'd use one and route it accordingly.
Maybe the heading is a bit misleading. The original problem was solved but I got concerned and a bit puzzled by the way Multi Mono works.
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  #19  
Old 01-31-2022, 07:10 AM
oortone oortone is offline
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Default Re: Multi mono - Singal generator out of phase

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Originally Posted by MrDibS View Post
I’m not following what you are saying.

Yes I mean oscillators. Generator is a synonym for oscillator, hence the name of the plugin.

There is no phase coherency issue with using multi mono plugins. Two oscillators, however are not guaranteed to line up every time no matter what kind of channel they are dropped into. Rich said the exact same thing as an oscillator is microscopically randomized. Nothing I said contradicted him in the least.

Some of the brightest minds on this forum have patiently and respectfully explained to you that your test is flawed. To test phase, one must use one mono oscillator routed to both left and right. I’m not sure what’s left to discuss here.


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It's not just generators. I tried the same thing with a delay (Waves Super Tap 2 Taps) and I can provoke that one to get out of phase too when using Multi Mono - although they have exactly the same delay time L/R. If I use the more apporpriate Multichannel version there are no such phase issues. (<< Please read this sentence two times, so you get the point.)

So this confirmed exactly what I was worried about. Phase coherency is not guaranteed in Multi Mono plugins. So anyone using these in a multi channel setup in abscence of a proper Multichannel version should be cautious.

And if I'm wrong by definition like you seem to think please provide some kind of refrence to what you claim about the internal algorithms in ProTools.

addendum: I just found this in ProTools Reference Guide 2021.10. Anyone who knows about Ambisonics and the fact that the text address Multi Mono specifically might agreeI have a point:
Quote:
Do not use multi-mono plug-ins following any Ambisonics plug-ins. Likewise, any plug-in processing of source tracks should only be inserted before Ambisonics plug-ins.
page 1309

Last edited by oortone; 01-31-2022 at 07:36 AM. Reason: found more facts
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  #20  
Old 01-31-2022, 07:25 AM
MrDibS MrDibS is offline
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Default Re: Multi mono - Singal generator out of phase

Omg.

THEY ARE NOT PHASE LOCKED BECAUSE THEY ARE TWO SEPARATE INSTANCES. (Read this six or seven times to really drink it in).


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