Pitch Bend Modulation Question

[Boss Level Music]

Ok, here's the scenario. I've got a MIDI clip playing with the pitch bend parameter modulated to pitch the clip down 12 semitones over 4 bars. Now I decide to launch a different clip on the same track half way through the first clips playback. This new clip with no modulations is now stuck playing at -6 semitones. I'm using 8.2.2 and 8.2.6

Why is this? Shouldn't the pitch bend reset to a 0 point at the launch of a new clip? Is it supposed to work like this? Am I going crazy?

[Warrior Bob]

If I understand correctly, this is expected behavior: you've sent pitch bend messages that say "now the pitch is bent this far" in the first clip, and have never sent a message that says "now it is back at zero." The synthesizer is acting based on the information it receives.

This seems a bit counterintuitive at first, as it's easy to think of the pitchbend envelope as the current "state" of the pitchbend, just like it would be if you were playing a synth. So if you have a clip with no pitchbend information in it, you'd be inclined to think of the pitchbend knob as centered.

But that isn't how pitchbend messages work in MIDI: messages are only sent when a new position is set. So when you play a clip with no pitchbend information in it, what really happens is that the pitchbend stays right where it is.

It's been a bit since I last tried this, but I believe the workaround is to send an explicit "pitchbend is centered" message at the beginning of your new clip. You do this by setting the pitchbend envelope to have a control point at 0.

Hope this helps - do correct me if I'm mistaken.

[Boss Level Music]

Thanks for the reply Warrior Bob.

You've confirmed my assumption, and were absolutely correct. I still find it odd that adding a breakpoint is necessary, but that does the trick. I guess it's something to do with the whole "relative value" of clip envelopes, of which I've still not reached a complete understanding. I suppose it's time for me to learn a little more about how MIDI messages work.

I'm still confused about how adding a single breakpoint, which can be anywhere in the clip, tells a "relative value" control to return to center immediately, while omitting the breakpoint causes the clip to act like there is no modulation. It seems like the breakpoint acts as a kind of notifier that says to Live "hey, pay attention to this".

And about the "relative" part. If for instance, I play a clip with a pitch bend modulation equivalent to an octave. Half way through the first clip I launch a second clip with a pitch bend value of zero. Am I mistaken thinking that modulating the first clip by a "relative value" of zero mean no change at all?

Am I simply overthinking all of this?

Should I just shut up and make some damn music?

[Warrior Bob]

You've confirmed my assumption, and were absolutely correct. I still find it odd that adding a breakpoint is necessary, but that does the trick. I guess it's something to do with the whole "relative value" of clip envelopes, of which I've still not reached a complete understanding.

That's another thing entirely, which I'll summarize here.

For automatable parameters in Live (virtual knobs, sliders and such), it's possible to record automations in the Arrangement view, independent of any clips. These automations specify the position of the parameter over time. If there's no automation, then the paramter stays where it is. Simple enough.

However, you can also have automations in clip envelopes. Clip envelopes like that specify the effective position of the parameter as a percentage of the parameter's current value at that point. So if you've got a knob turned halfway up, then you can use a clip envelope to mess with it: clip envelope 100% means "use the parameter where it's set (i.e. halfway up)," 50% means "make the parameter half the value of what it's set to (i.e. 1/4 of the way up, in our example)". Clip envelopes cannot make a parameter act higher than what the knob is set to.

This is different from envelopes such as pitchbend, or MIDI CC envelopes - in this case, it's not automating a paramter, it's sending MIDI data down the chain.

I suppose it's time for me to learn a little more about how MIDI messages work.

This is always a good idea. I can't find the MIDI spec online anymore, but here's a summary that seems to get the right idea.

I'm still confused about how adding a single breakpoint, which can be anywhere in the clip, tells a "relative value" control to return to center immediately, while omitting the breakpoint causes the clip to act like there is no modulation. It seems like the breakpoint acts as a kind of notifier that says to Live "hey, pay attention to this".

Actually, every single change in your pitchbend envelope acts like such a notifier. You need that notification to do anything. No envelope points, no notification - hence, omitting that breakpoint means "keep doing what you're doing" - and if the last thing it was told to do is to hold the pitchbend somewhere, then it'll keep holding it there.

It's analagous to a MIDI keyboard. As far as the synth can tell, you've moved the pitchbend knob somewhere, and then never let go. If you had let it go, it would be getting a message about the knob's new position. The pitchbend knob on a keyboard only sends information when it changes position. The information it sends is "here is my new position," not "I have moved this much from my previous position." There is nothing relative about pitchbend messages.

And about the "relative" part. If for instance, I play a clip with a pitch bend modulation equivalent to an octave. Half way through the first clip I launch a second clip with a pitch bend value of zero. Am I mistaken thinking that modulating the first clip by a "relative value" of zero mean no change at all?

I'm assuming that by zero you mean center.

If your second clip specifies a new pitch bend value of zero (i.e. there's an explicit 0 message at the beginning, not an empty pitchbend envelope) then your synth should immediately cease bending notes - the pitchbend is now set to zero.

It's not an offset, it's an absolute position.

Am I simply overthinking all of this?

Should I just shut up and make some damn music?

No, I think it's good to be asking these things - I think it's important to learn your tools. I find that DAW software like Live actually makes it harder to learn, because things like MIDI concepts are hidden behind nice menus and visualizations. Which is nice, but it's hard to see what's going on internally unless you've learned it somewhere else.

Definitely go make some music - use what you've learned to give you more control :) And if you don't know how something works, and can't figure it out, just ask the question online, make a copy of your file, and move on. See if you can come up with a clever hack to do what you want to do in the meantime.

Hopefully this all made sense! Let me know if you need anything clarified.

[Boss Level Music]

Thank you again for taking the time to write such a thorough reply. It all made sense, well except for some of the technical stuff in the MIDI spec link but I'll get there. You've been immensely helpful.

[Warrior Bob]

Oh, of course! I'm happy to help where I can. I figured the question warranted a good long reply so that's what I gave it

Don't hesitate to ask if you have any further questions.

[Trypset]

what is the best way to record different variations of the same patch?

For example....I'm using a Microkorg....when I record into a clip slot only the first clip gets all the CC messages right....(like where the filter is)

All clips following the first are behaving not as expected and I can't figure out what exactly is making them jump.

I simply would like to record a patch that has all the CC messages set to how they sound....then continue making new clips with different knob settings. Any help?