Why don't midi feedback loops work?

[johnjaypl]

I can't create a midi feedback loop in a MUX.

More or less what I want to do is create a MUX where a received midi note is passed through to a synth but along the way that note is also sent to a delay module which hangs on to if for some time and then feeds it back somehere BEFORE the delay in the midi chain.

So with a 1 second delay any note sent into the MUX should be repeated at 1 second intervals forever.

But it doesn't work.

I can use the delay to feed forward. That is, a midi note in gets repeated 1 second later. But of course without feedback I only get one repeat.

What's up with this?

John

[MuTools]

It doesn't work because feedback loops are not supported. And there are also no plans to support it. It has to do with the nature of buffered DSP.

[johnjaypl]

It doesn't work because feedback loops are not supported. And there are also no plans to support it. It has to do with the nature of buffered DSP.

What does buffered DSP (You do mean Digital Signal Processing, don't you?) have to do with routing of midi notes and commands?

And, while I can imagine how one can create an unstable midi loop using feedback that won't work, it's just one of the many things one can do with midi designs that won't work.

Perhaps you're not really understanding what I'm asking for here. I assure you that what I'm talking about is certainly possible. Maybe I need to post an example or something.

No midi feedback, bummer, that cramps my creativity.

John

[MuTools]

It doesn't work because feedback loops are not supported. And there are also no plans to support it. It has to do with the nature of buffered DSP.

What does buffered DSP (You do mean Digital Signal Processing, don't you?)

Yes.

have to do with routing of midi notes and commands?

It's too technical too explain.

Bottom line is that MU.LAB does not support signal paths where the output of a module loops back towards it's input, in whatever way.

Perhaps you're not really understanding what I'm asking for here. I assure you that what I'm talking about is certainly possible. Maybe I need to post an example or something.

Ok.

No midi feedback, bummer, that cramps my creativity.

I'm sorry.

As a solace: Sometimes creativity is triggered more by technical limits than by technical possibilities.

[johnjaypl]

Bottom line is that MU.LAB does not support signal paths where the output of a module loops back towards it's input, in whatever way.

That may be a MU.LAB architecture limit but it certainly is not a general technical limitation- especially in the case I'm talking about where we're dealing with low frequency events. In my case all that is required is that when an event pops out of a midi module it enter the queue of the module it's connected to regardless of where that module is in the midi chain.

I wonder if this architecture limit has something to do with why I can't record midi coming from a track and then through a rack. Maybe a diagram of some sort describing how MU.LAB works would help explain the working features and supplement the intentionally minimal documentation. Surely you can see what a struggle it is for me to figure this out by trial and error.

Sometimes creativity is triggered more by technical limits than by technical possibilities.

True enough but somtimes things are just too limited. And all the time it takes to try somehhing, find out it doesn't work, find out it wasn't designed to work- well I'm sure you can understand that it could quench the spark of creativity a bit.

I could understand if I was trying to do weird stuff but I'm just connecting a couple of modules with a wire, which MU.LAB is happy to do- no warning or errors that feedback is not permitted. Then no data! Surely you don't think that's a good way for a program to behave?

John

[MuTools]

That may be a MU.LAB architecture limit but it certainly is not a general technical limitation- especially in the case I'm talking about where we're dealing with low frequency events. In my case all that is required is that when an event pops out of a midi module it enter the queue of the module it's connected to regardless of where that module is in the midi chain.

Sure, that is the case.

The only thing is, if you follow the chain further on, and in some way it loops back to the original module, then that won't work.

I wonder if this architecture limit has something to do with why I can't record midi coming from a track and then through a rack.

No, nothing to do with that. Recording events straight from a module's output is on the whishlist and will be implemented in a future version.

Maybe a diagram of some sort describing how MU.LAB works would help explain the working features and supplement the intentionally minimal documentation.
Surely you can see what a struggle it is for me to figure this out by trial and error.

I'll update the docs so it mentions that MU.LAB does not support feedback loops.

[robenestobenz]

In the meantime, jthalamus and jsoundbus are both great plugins for teleporting audio and MIDI around the place. Available here. Windows only BTW.

[liquidsound]

Neat stuff. Thanks.
(This is why I am using Windows. I was a MAC user from the very beginning writing databases with Helix express on a Mac SE but... you know the rest it's history).

[johnjaypl]

Sure, that is the case.

The only thing is, if you follow the chain further on, and in some way it loops back to the original module, then that won't work.

That's disapointing. If if didn't have some of these basic limitations MU.LAB could be an extremely powerful tool. Even with the limitations it's powerful but it's got a arm and a leg tied behind its back.

Recording events straight from a module's output is on the whishlist and will be implemented in a future version.

That's good.

In the meantime, jthalamus and jsoundbus are both great plugins for teleporting audio and MIDI around the place. Available here. Windows only BTW.

Thanks! The description of jthalamus looks good. If I understand it, I can put it in my midi path and use it to record midi anywhere I want. Is that correct?

I don't understand the routing part yet, I'll look into it further along with jsoundbus.

John

[MuTools]

So with a 1 second delay any note sent into the MUX should be repeated at 1 second intervals forever.

This sounds like a MIDI delay/echo to me where you set the feedback to 100%.

Maybe you can find such plugin in VST format. Maybe such plugin will be added as a MU.LAB module in a future version.

[liquidsound]

See if this helps. I just did a quick search on Jo definition.
http://www.pjb.com.au/midi/midiecho.html

[johnjaypl]

So with a 1 second delay any note sent into the MUX should be repeated at 1 second intervals forever.

This sounds like a MIDI delay/echo to me where you set the feedback to 100%.

Maybe you can find such plugin in VST format. Maybe such plugin will be added as a MU.LAB module in a future version.

I simplified what I was trying to do to make it easier to explain the midi feedback problem. I wanted to use various kinds of feedback loops not just echos. Basically send a note in and let it evolve in varous ways, bouncing through midi modules, making a sound, and then looping through again.

I do have a midi delay vst that I'll try to use to get a similar result to what I was going for but it forces a different way to think about what I'm doing and I don't think it will be exactly the same. That is, the note won't be able to evolve, the modules down stream will have to evolve.

Your plugin won't help me much because I'll want to control the delay from other modules. I need to use VSTs

I do appreciate the thoughts though.

John

[liquidsound]

Maybe, and I am not so familiar with these, if you load inside the MUX an instance of Bidule or AudioMulch, they may have something that could function in this area.

I know AudioMulch is great with Loops but I have only a demo and I did use it for experimenting with audio and not MIDI which it's also very capable at the current version.

The rest it's out of my league.

[johnjaypl]

Maybe, and I am not so familiar with these, if you load inside the MUX an instance of Bidule or AudioMulch, they may have something that could function in this area.

I know AudioMulch is great with Loops but I have only a demo and I did use it for experimenting with audio and not MIDI which it's also very capable at the current version.

The rest it's out of my league.

Thanks, I'll take a look at the plugins.

John