Some MPE related issues and findings

[klontart]

Hi all,

I recently acquired a Trigon desktop model, and love it. This thing has a lot of character.

Anyway, I've been digging into the whole MPE thing, and found some issues. This is with Push 3 as my MPE source via Live. Here is what I found:

1. When powering up the synth in MPE mode, it won't respond to incoming notes. I have to switch MPE off and on again to make it respond.

2. When driven with poly AT notes in normal (non-MPE) mode, the Trigon will respond as expected with per-note, individual expression. However, when driven in MPE mode, the synth responds monophonically to pressure, even while I can see in Live the signal provides poly pressure.

3. When selecting LFO amount as the target in the Aftertouch section on the synth, the effect is always mono, in both PAT and MPE modes. Now I know that there's only one global LFO available, but I was hoping there would be a per-voice VCA letting the LFO signal in, so I would be able to control the amount of LFO on a per-voice basis.

Does any of this sound familiar? Or is this somewhere in my setup?

Cheers, Robert

[Elric]

Unfortunately, the inventor (company) ...Sequential has crappy MIDI implementation.
(But my Pro3 sounds awesome!)

[Haster76]

Hi all,

I recently acquired a Trigon desktop model, and love it. This thing has a lot of character.

Anyway, I've been digging into the whole MPE thing, and found some issues. This is with Push 3 as my MPE source via Live. Here is what I found:

1. When powering up the synth in MPE mode, it won't respond to incoming notes. I have to switch MPE off and on again to make it respond.

2. When driven with poly AT notes in normal (non-MPE) mode, the Trigon will respond as expected with per-note, individual expression. However, when driven in MPE mode, the synth responds monophonically to pressure, even while I can see in Live the signal provides poly pressure.

3. When selecting LFO amount as the target in the Aftertouch section on the synth, the effect is always mono, in both PAT and MPE modes. Now I know that there's only one global LFO available, but I was hoping there would be a per-voice VCA letting the LFO signal in, so I would be able to control the amount of LFO on a per-voice basis.

Does any of this sound familiar? Or is this somewhere in my setup?

Cheers, Robert

Hi Robert,

Thanks for sharing! The MPE startup issue sounds like a known firmware quirk. The mono pressure response in MPE mode is common—some synths treat pressure globally, not per note. And with only one global LFO, per-voice LFO amount control isn’t possible yet. Hopefully future updates will improve this!

Cheers!

[g3o2]

2. When driven with poly AT notes in normal (non-MPE) mode, the Trigon will respond as expected with per-note, individual expression. However, when driven in MPE mode, the synth responds monophonically to pressure, even while I can see in Live the signal provides poly pressure.

3. When selecting LFO amount as the target in the Aftertouch section on the synth, the effect is always mono, in both PAT and MPE modes. Now I know that there's only one global LFO available, but I was hoping there would be a per-voice VCA letting the LFO signal in, so I would be able to control the amount of LFO on a per-voice basis.

Does any of this sound familiar? Or is this somewhere in my setup?

Cheers, Robert

Trigon 6 has got a very generous AT implementation. Nothing to criticise there.

Ad 2) MPE does not use polyAT but channelAT and that's because it uses one channel per voice, unlike polyAT which operates on a single channel. That’s how MPE achieves polyphonic pitch slides and timbre control. The caveat: sequencing needs to deal with this mass of messages.

Ad 3) The global LFO is monophonic, alright, but you've already got the best polyphonic LFO in the world on your Trigon 6: oscillator 3 can operate in low frequency mode and poly mod gives you the power of routing to any destination except osc 3. Just modulate Freq3 with AT and you should be all set for either MPE or polyAT. Btw osc3 has keyboard tracking, which is also applied when using osc3 as LFO. So you can still route global LFO to osc3 frequency and, with keyboard tracking on osc3, you will have a sort of polyphonic response. Caveat: you lose one oscillator.

Don't want to sacrifice an oscillator, then use this: your fingers. Instead of modulating a cyclic destination, directly route MPE-Z or AT to filter and amp at the same time. Let your finger play a natural vibrato by rocking your wrist (thanks to MPE-X, be sure to  align the slide range on both synth and controller) and gently apply pressure at the same time while still rocking your wrist - the index or middle finger works best for this. Or just gently apply the pressure and rhythmically pulsate with your finger. With MPE, your fingers become the LFO.