Is multi-channel VST input possible?

[chr15m]

Some VSTs are able to take more than 2 channels as input. I can't seem to get it working with OpenMPT, but it may be the plugin I am using. If it does work, how are the channels divided up? I guess what would be ideal (for me) is if e.g. the first source going into the VST goes to the first two channels, then the next source goes into the next two channels, and so on.

[Saga Musix]

Currently this is not possible, apart from going through some "host-inside-VST" solution (I think energyXT has been brought up a couple of times in the forum to accomplish this but I cannot vouch for it). I do have some unfinished code that would allow for arbitrary input routing, though there are still a few open questions. I initially wanted to finish this code in the context of more complex modular graph routing, but it might make sense to take things a bit easier and just have this part of the feature available before the other stuff happens (which is potentially never).

[chr15m]

Ah ok, yes a solution which allows that simplest input routing would be awesome!

BTW is there any way to sponsor your work? I am using OpenMPT every week to write music and I believe in supporting the software I use regularly.

[Saga Musix]

Thanks, you can leave a donation via https://openmpt.org/donate which is used to cover our hosting and code signing costs.

[LPChip]

Maybe its not the same, but you can create multiple instruments, and assign it to the same VSTi, but give each instrument a different midi channel.

[chr15m]

Donated, thanks!

Maybe its not the same, but you can create multiple instruments, and assign it to the same VSTi, but give each instrument a different midi channel.

This is indeed useful, thanks. I have done this before.

A bit more info about my use-cases for multi-channel audio into VSTs. I am using PdVST which allows me to embed the Pure Data patching environment inside OpenMPT. This is working great for single channel effects, and also for final mastering effects with all channels mixed together. I'd like to also be able to design the following kind of effects using PdVST:

* Effects that allow me to mix or choose between channels. For example two drum breaks coming in on two different stereo channels. On each beat I can subtly alter the mix between them to get an interesting dynamic sound where it's never playing exactly the same drum sound. I do this at the moment using one beat into each of the left and right channels and mixing to mono and it sounds cool. Would be great to support stereo.

* Effects which let one channel influence the sound of another. For example using one channel as a ring mod against the other channel, or vocode one channel against the other. Or using one channel to trigger gating on the other channel or set the envelope of the other channel based on the sound e.g. drum track's power envelope sets the volume of a synth sound to give it a rhythmic feeling. Can sort of do that with MIDI note triggers but can't do the ring mod of one sound into the other.

* Multi-channel mixing live. I can run all channels into one plugin and then change the mix of individual channels from there in real-time. Can also apply e.g. stutter effects or other custom effects/algorithms to only selected channels or whatever. At the moment you can have a "master" plugin but it receives all the channels mixed together so anything you do is applied to all of them.

Thanks again for your work on OpenMPT all these years!