The Official Sequential/Oberheim Forum

SEQUENTIAL/DSI => Mopho/Tetra => Mopho X4 => Topic started by: wbajzek on January 25, 2018, 07:35:16 AM

Title: Weirdness when automating parameters in Ableton Live
Post by: wbajzek on January 25, 2018, 07:35:16 AM
This is probably my own mistake somewhere, but I'm having trouble figuring it out. I made a sequence in Live and ran it through my X4 using an External Instrument device. I had the X4's local control turned off. So far so good. The patch was basically a single square wave, with cutoff, resonance, and filter env amount set to 0. Then I made a second pass in "arrangement overdub" mode and tweaked those three parameters throughout the performance. When that was done, I restored the patch to its original state, and then tried to freeze the track. It starts off with a different filter setting, and one of the oscillators gets dropped a couple of octaves, and probably some other weirdness that I definitely did not record into it. What am I doing wrong?
Title: Re: Weirdness when automating parameters in Ableton Live
Post by: chysn on January 25, 2018, 06:56:53 PM
Your description makes it sound like the octave change is happening on playback (from Ableton), and not via MIDI (from the X4).

If that's the case, it sounds like your audio track might be warped, which is something Ableton does to maintain tempo. Go to the Arrangement View and double-click on the waveform on the track. A "Sample" panel should open up at the bottom of the screen. Make sure that the "Warp" button is off, and try playback again.
Title: Re: Weirdness when automating parameters in Ableton Live
Post by: wbajzek on January 25, 2018, 07:49:01 PM
Hmmm... that’s definitely not it. This is before/as the audio is being recorded, not after the fact, and the synth’s settings have definitely changed. Oscillator 2 was getting dropped two octaves.

I can try to make a video of it or something. I figure it’s something to do with my global settings, but I can’t figure out what. It’s like the midi messages it’s sending are not the ones I recorded using the Mopho as the controller.
Title: Re: Weirdness when automating parameters in Ableton Live
Post by: chysn on January 27, 2018, 04:54:01 AM
Okay, sorry, I misunderstood. Unfortunately, I'm a little sketchy when it comes to Ableton and MIDI. I haven't used MIDI much since I started using Ableton. And Ableton doesn't have a detailed MIDI event editor, so it would be hard to see what, exactly, is going on.

I'd start by disabling NRPM messages on the X4, and play back the track again, as NRPM is pretty much the only way to modify the X4's patch via MIDI with Ableton (AFAIK, Ableton actively filters away sysex messages).
Title: Re: Weirdness when automating parameters in Ableton Live
Post by: wbajzek on January 27, 2018, 09:03:13 AM
I haven't figured out what the problem is, but I've figured out how to avoid it, thanks to your suggestion. If I configure the X4 to only send and receive CC, it works. I think that when recording NRPNs, Live does something wrong. In the process I described above, if I only adjust the cutoff frequency, I see 4 parameter changes in the midi clip. I thought NRPNs would do two.
Title: Re: Weirdness when automating parameters in Ableton Live
Post by: chysn on January 28, 2018, 06:58:09 AM
I haven't figured out what the problem is, but I've figured out how to avoid it, thanks to your suggestion. If I configure the X4 to only send and receive CC, it works. I think that when recording NRPNs, Live does something wrong. In the process I described above, if I only adjust the cutoff frequency, I see 4 parameter changes in the midi clip. I thought NRPNs would do two.

There should be four CC messages for each parameter change: least significant byte (LSB) and most significant byte (MSB) of the parameter number, and LSB and MSB of the value.

There seems to be some controversy (or, maybe a better term is "lack of standardization") about how the MSB is to be interpreted in the absence of the LSB. There's a thread that goes into some depth on this with respect to Mopho and Trigger Finger Pro (http://forum.davesmithinstruments.com/index.php/topic,894.msg10624.html#msg10624), and it's a decent bet that you're the victim of a similar issue.

There's also some good information on the Ableton forum (https://www.ableton.com/answers/what-s-the-best-way-to-send-nrpn-data-from-ableton).

I think the tl;dr answer is that Ableton and NRPM don't mix with DSI instruments.