MPE and less than 16 channels

[jsterne]

Hi Everyone,

I've now run into two cases of software where the designers assumed full MPE support means all 16 channels, rather than a range of more than 1 to 16 channels of MIDI. This is an issue using splits in MPE mode in Bitwig and in Volt. I'm waiting for a reply from Bitwig (the first one referred me to section 3.1 of the MPE spec, which does not actually say a MPE sound generator has to use all 16 channels, which is what was suggested in the email but it got me to actually read the spec, which was worthwhile), and the iOS Volt developer is cooking up a fix that allows less than 16 channels (GREAT sounding synth, by the way), but I'm curious if others have run into this and how they're dealing with it.

I love the "splits" option on the Linnstrument but it's a bit disappointing that the software world doesn't seem ready for MPE splits. Ironically, I was successfully doing this in Live, where you can kludge together multiple channels for MPE sound generators (with limits).

[mrspiral]

I'm not doing MPE split work yet, Jonathan. One instrument at a time is enough to sprain my brain... But keep us informed, especially about the Volt thing, as I am about to get into that instrument more.

[jsterne]

It’s not so much two at once as switching sounds for a part, or a drone (that I can modulate) and a melody.

[John the Savage]

What you need is a MIDI channel filter. I use "Channels" by MIDIflow on the iPad to limit which channels each app is listening to. Granted, channel filtering should simply come stock on all MPE synths, but it seems that most developers haven't caught on to that yet. All the Roli soft synths, for instance, have channel filtering baked in. I don't typically use my laptop for MPE work, and haven't yet tried to set up splits in Bitwig, so I don't know what to suggest there specifically. But ya, channel filtering is paramount; especially if MPE synths are to ever find their way into larger setups: studios, live rigs, and other real-world applications. It will be particularly needed when the hardware industry catches up. Anyway...

Cheers!

[jsterne]

I do use MIDI channel filtering (very common in desktop software, and I used AUM for that in iOS). The issue is that with Bitwig, it will only support MPE instruments that use all 16 channels. Here's what support said:

"you can use as many instrument selector devices with as many chains to switch between as you need, it is just that splitting of MPE zones into 1-8 and 9-16 channels is not possible in Bitwig Studio."

This is frankly shocking to me given how Bitwig is advertised ("fully modular!" "full MPE support!"), but then, software always has a gotcha moment.

So: I can EITHER use the Linnstrument in MPE mode with Bitwig, OR I can use the Linnstrument's "splits" feature to access two sounds at once, but I can't use both. Ironically, this is something that easy to do in Ableton Live: run 8 MIDI channels into one MPE VST, and the other 8 MIDI channels into another VST.

I logged a feature request and the support person said "I will add it to the wish list." I suspect that means it might happen in some far off future. This is a case where I suspect a note from Roger to the Bitwig development team might make more of a difference than from me, if he's willing.

On the iOS front, I am happy to report that this morning the developer for Volt solved its stuck note problem (I've been beta testing for him), and it is now a great sounding analog modelling poly synth for iOS and works flawlessly with the Linnstrument.

[Roger_Linn]

Thanks for bringing that to my attention, Jonathan. I’ll send Bitwig an email about this.

[Echoes in the Attic]

I'm a bit confused by this issue. I don't need to use all 16 channels of midi for mpe in Bitwig. Maybe I misunderstand, but Bitwig will record whatever midi channels are sent per note if you want it to. So if you have a rack with two instruments that have filtered midi channels, it should work. Question: What are your track midi settings? By default it is From channel "All", To channel "1". This has an effect of reassigning the midi channels coming in from an mpe device for some reason to always use the lowest available channel in a rotating fashion. If you change it To "Same" from "1", it keeps the midi channel that was played. I don't see why what you want to do wouldn't work with this setting.

Edit: It looks like Channel set to "Same" doesn't actually keep the channel that was played if multiple notes overlap. It sequentially increases the midi channel for each overlapped note played, rather than keep the channel played.

[jsterne]

Thanks Roger!

Echoes: thanks for your suggestion, but I've spent a few hours troubleshooting Bitwig before I wrote to them (I absolutely hate troubleshooting when I want to be making music), and tried multiple MIDI configurations in the track, device and instrument switcher (all of which offer MIDI filtering). Bitwig support said what I wanted to do couldn't be done. I've tried every "this should work" scenario I can think of. If you've actually achieved two MPE instruments playing two different lines on separate sets of channels in Bitwig, could you post a sample set setup or a more detailed walkthrough of how you did it or something?

Just to clarify, in case it's not clear, what I want is:

Two separate tracks, each with an instrument switcher. Each track set up for a different split of 8 channels of channel per note on Linnstrument. Then I can switch sounds for different songs in a set and still have access to two different sounds for playing.

[Echoes in the Attic]

Hmm, ok I guess I should take Bitwig's word for it if they say it doesn't work. I'm just curious I guess because I haven't had this need. So you want to play the two tracks simultaneously. One responding for example to midi channels 1-8 and one responding to 9-16?

[jsterne]

Yes. And when I set it up this way all sorts of problem arise.

[BobDog]

I Just tried this and it seems to work fine here, including recording.

I set linnstrument splits up so that no tracks overlap, Left split main = 9, per note channels 9-16. Right split main =1, per note channels 1-8

In BW 3 I have two tracks, each track has channel (all, same) and P.Bend (PB->Expression turned off).

Channel filter on each track, one track with 1-8 enabled and one track with 9-16 enabled.

Polysynth on each track.

What exactly doesn't work for you?

[Echoes in the Attic]

I Just tried this and it seems to work fine here, including recording.

I set linnstrument splits up so that no tracks overlap, Left split main = 9, per note channels 9-16. Right split main =1, per note channels 1-8

In BW 3 I have two tracks, each track has channel (all, same) and P.Bend (PB->Expression turned off).

Channel filter on each track, one track with 1-8 enabled and one track with 9-16 enabled.

Polysynth on each track.

What exactly doesn't work for you?

Yep I just tested the same thing and it works fine here as well. I left the main channel on 1 and had the left as channels 2-8 and the right as 9-16, using Bitwig's Channel Filter on each track. I had Equator on one track allownig channels 1-8 and another track with cypher allowing channels 9-16. Set both tracks to record in and the linnstrument played each instrument from it's own split.

So I'm not sure what the problem is either.

So to be perfectly clear: You can use the splits at the same time as using mpe, with each split controlling a different MPE instrument. In different layers of a rack or on separate tracks.

[jsterne]

Hi Everyone,

First, a big thank you to Echoes and to BobDog for trying it out. There are MIDI channel filters on the track, the Instrument Selector, and the instruments themselves. What I needed was the channel filter PLUGIN/device at the front of the track. That works perfectly.

THANK YOU. I can now use Bitwig with splits, which is great. I wish tech support knew.

I have two followup questions, which is about the use of channel one for general information. Do I leave channel 1 enabled on the Channel Filter plugins for both channels in Bitwig? And do I leave it enabled on BOTH splits of the LinnStrument, or do I turn it off on the splits but channel 1 will send CC information? This bit is also confusing to me.

AND -- it seems that Bitwig turns off "record" in one of the channels when I'm messing with the other (like adding pressure as a controller). Or maybe I'm inadvertently doing something, but it keeps happening. Is there a workaround?

[Echoes in the Attic]

I don't understand how Bitwig Tech support doesn't know that you can do something fairly straight forward. Bit scary.

I don't know how you can use the master channels with a split, but you can't have the same for both I guess. They would have to be different. But then the software instrument would have to know to respond to that master channel. Not sure if you can change the master channel on software like Equator and Cypher. You certainly can't on non-mpe devices. I haven't figured out how to use the master channel for things like Kontakt and Omnisphere which aren't technically MPE compatible but work as multi-layered devices.

Not sure what you mean by the second point. You mean the record arm button turns off when you are playing with the other split?

[jsterne]

Not sure what you mean by the second point. You mean the record arm button turns off when you are playing with the other split?

Thanks. Yes, that's what I'm asking. It's more like when I edit the other track in Bitwig than playing splits though.