Help sought: Octatrack and Prophet Rev2 Multi-mode

The Lounge Other Gear
1

I’m having a bit of trouble with my set-up, maybe someone can help?

I’d like to drive my Rev2 in multi-mode, on channels 15 and 16, from my Octatrack. I’d also like to mix the audio from the Rev2 in the OT. Here’s what I have so far:

in the Rev2

Multi-mode: on
Local: off
MIDI Ch: 15

Main audio outs -> OT AB
Aux audio outs -> OT CD

Rev2 MIDI Out -> OT MIDI IN
OT MIDI OUT -> Rev2 MIDI IN

in the OT

MIDI tracks 1-4: ch 15, none of the bank/prgm options set. Some trigs for testing on MIDI track 1 and 2.

MIDI tracks 5-8: ch 16, none of the bank/prgm options set. Some trigs for testing on MIDI track 5.

Audio 1: thru, with a trig, listens on A B
Audio 2: neighbour

Audio 5: thru, with a trig, listens on C D
Audio 2: neighbour

(I’ve also run it without the Thru trigs, bypassing the Thru machines, but setting DIR in the mixer fully up, for both AB and CD).

current outcome

Everything works as hoped for the “top layer”, MIDI Ch 15 stuff. I can hear the sound, using both the Thru machine, or DIR. The OT inputs for AB flicker. I can play the keyboard, and when MIDI Track 1 is selected, I hear the notes with the expected sound from the Rev2. I can also record and play back MIDI into and out of the MIDI Track, and also MIDI Track 2 (on the same MIDI channel).

But for the 2nd Rev2 “layer”, which should respond to MIDI Ch 16, I get nothing. No OT input lights flicker. IIRC (currently working), I can record MIDI notes to OT track 5 (set to ch 16), but they don’t seem to cause sound to play from the synth.

If I have LOCAL on, on the Rev2, and I manually choose the layer B, I get sound at the OT inputs CD (with the expected LEDs meters flickering)… so it looks like the Rev2 is ignoring MIDI (or maybe the OT isn’t sending MIDI).

I’ve tried a couple of configurations around this basic framework, but don’t know where to go next.

Any thoughts?

(Perhaps this should move to “Other Gear”?)

2

The two layers are referred to as Layer A and Layer B. By default, Layer A is
always active. But all factory programs also have a “B” layer, even if that layer
isn’t currently enabled. To hear Layer B in isolation, press the edit layer b button

I think its inactive thats why your getting nothing

3

You are bound to have some problems with this setup because the Rev2 transmits MIDI on the same channel as the base channel for receiving MIDI.

You can use the OT’s autochannel feature to direct incoming MIDI from the Rev2 to the active MIDI sequencer track, but you will need to use fiddly workarounds like muting or blocking MIDI or audio channels to prevent the problems you are encountering.

Do you have any other gear?

One way to fix things would be to use a MIDI processor between the Rev2 MIDI Out and the OT MIDI In to rechannelize the messages.

4

Thanks.

So, perhaps I need to engage “stack a+b” for each patch I want to use in multi-mode?

I’ll try that.

5

Thanks!

I forgot to mention that I had already set the OT Auto-channel to 15.

I recently had the Rev2 set up without multi-mode, with Local off, and with more synths further down the chain, all set on different channels. Selecting the OT MIDI track with the matching channels allowed me to play the Rev (on one channel) and whichever other synth I wanted, using the Rev2 as master keyboard and the OT as “channel selection”. From what I can see, the only difference in the current setup is that the Rev should respond on two MIDI channels, but doesn’t.

I’m not sure what a MIDI processor would add to this set-up that I actually need. Could you expand a bit?

6

I’m gonna move this to “Other Gear” because I think it’s more a Rev2 problem than an OT one (at the moment).

7

Yes.

8

Well, this is odd.

If I set the Rev2 to MIDI CHANNEL 1, then set the OT to send on CHs 1 and 2, then I get the notes I asked for, played by the sounds I ask for on Rev2 Layers A and B respectively.

If I set the Rev2 to MIDI CHANNEL 8, then set the OT to send on CHs 8 and 9, then I get the notes I asked for, played by the sounds I ask for.

And so on up to 14/15.

If I set the Rev2 to MIDI CHANNEL 15, then set the OT to send on CHs 15 and 16 (my original scheme), then I hear Layer A on 15 as expected, but not Layer B on 16. Setting the OT to send on 15 and 1 gives me what I was expecting to hear. Likewise if I shift up again and set the Rev2 to Ch 16, and the OT to 16 and 2.

It seems like the Rev2 does do Multi Mode, as described in the manual, set to MIDI Channel 1-14. It doesn’t follow the manual when set it to MIDI Channel 15 or 16: instead it responds on Ch and (CH+2 modulo 16). This looks like a bug. I shall contact Sequential.

Having gone through this, I can change up my set-up to work the way I want, but I have to use different MIDI channels. That’s acceptable.

FWIW, with Multi Mode on, I don’t have to explicitly activate Layer B using any of the Split/Stack/Edit buttons.

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