Automated volume via midi CC#7 not tracking [solved]; slave tempo jittery [probably due to Ableton midi timing issue]

    I'm trying to set up midi automation for rig switching, stomp toggling etc. Our band has a clicktrack and synths running along from a laptop so I'm trying to program the midi commands in Ableton Live.


    My first impressions are that everything works as expected except for continuous controls like volume (cc#7). Looking at the page in the Kemper's system menu that shows the values of the volume, wah and pitch pedals as black bars, I can see the volume bar moving when dragging the automation line up and down "manually" (ie., using a mouse or trackpad). But when playing back a pre-programmed volume change -- say, volume at maximum, then steadily decreasing to zero -- the Kemper's volume doesn't follow until it's zero.


    [Blocked Image: http://i.imgur.com/q2d0BiN.jpg]


    In the example above, the Kemper would do nothing until the third bar, where it would suddenly go silent and show the tuner. Am I doing something wrong? This is the first time I've tried to program an external device via midi so I might be. It works perfectly well with the volume pedal on my FCB1010 (with Uno4kemper).


    Something else I've noticed is that the Kemper adjusts its tempo to the midi signal, but it doesn't remain steady. While testing, I had a track running at 74bpm in Ableton Live, and the Kemper's tempo fluctuated between 73.6 and 74.4. It's accurate enough for my purposes (timed delays, mainly) but I was just wondering what was going on.

    This is supposed to be a feature for guitar players that use a volume pedal and want to remotely access the tuner screen without having to toggle the chickenhead. If you do not want this to happen simply set the pedal range in the Kemper to -4,9 instead of -5.0.

    Sorry, I think I was unclear. I didn't mean to say that the tuner screen appearing was the problem. In fact, that's one thing that works as expected: when CC#7 reaches zero, the Kemper does exactly what it does when my volume pedal is all the way in the heel position: it goes silent and shows the tuner, which is what I want it to do.


    It's just that it doesn't respond at all before that. The volume doesn't change and the volume bar in the system screen doesn't move until the value of CC#7 is zero, so gradual volume fades or swells are impossible.


    Again, this is only when playing back a programmed volume curve. When I move the CC#7 automation nodes/curve in Ableton Live manually, the Kemper does respond to the intermediate positions.


    Edit: I read somewhere that some devices don't respond to the "lines" in an automation curve, only to the "nodes", but in this case adding intermediary nodes to the slope doesn't help.

    I just set up CC#7 in Logic, value 127 from bar 1, then a node at bar 3 at value 127, next at bar 7, value 0. The Profiler fades Volume down to 0 as expected. Maybe it is a setting in Ableton that does prevent continous data from being sent?

    Thanks for your replies, guys, and thanks for testing Helge. You're both right: the problem isn't the Kemper but Ableton Live, and I figured out the solution. Ableton Live has surprisingly few settings -- which is a good thing: usually it all just works the way you want without going through endless menus -- a bit like the Kemper really! So I had to look elsewhere.


    I had already noticed that adding intermediary nodes to the curve didn't help -- I mean like this:
    [Blocked Image: http://i.imgur.com/FwhoxrR.jpg]
    Playing back the example above, the Kemper again didn't respond until the curve reached zero.


    Then I remembered Ableton Live also has a "drawing mode" where, instead of "constructing" a curve by strategically positioning nodes, you simply "draw" it freehand into the clip. I gave it a try. The result looks like this:
    [Blocked Image: http://i.imgur.com/AvLCt1f.jpg]


    And -- surprise surprise: this time it worked!


    Coming out of drawing mode, I took a closer look and realized the curve was (of course) still made up of nodes and lines -- just lots and lots of them, as you can see in this close up:
    [Blocked Image: http://i.imgur.com/Xu9UHXE.jpg]


    But there was one important difference. If you look closely, you can see there are only horizontal and vertical lines. For every tiny volume drop that makes up the curve, there are two nodes right above each other, with a vertical line between them, and then a horizontal line to the next drop. I figured that was probably the reason it didn't work before.


    So I tried constructing a curve again using the node positioning method, only this time I did it with discrete steps like this:
    [Blocked Image: http://i.imgur.com/3Ke4GrD.jpg]


    And sure enough, it works. So -- for some reason slanted lines from node to node don't work, but vertical drops do. You can make the steps in the curve as small as you want, of course; freehand drawing mode makes them tiny enough to ensure smooth volume fade ins and outs.


    That's one problem solved. The other one isn't really a problem, just weird: why does the tempo in the Kemper fluctuate when slaved to an external midi device?

    Many devices send out a jittery midi clock-the Profiler simply responds to what he receives at the MIDI in-you will probably see the same result if you connect any other device to your clockmaster and look at their BPM settings. Back in the day when i was using hardware sequencers and drummachines it was a common problem.

    Quote from Lambik

    Many devices send out a jittery midi clock-the Profiler simply responds to what he receives at the MIDI in-you will probably see the same result if you connect any other device to your clockmaster and look at their BPM settings. Back in the day when i was using hardware sequencers and drummachines it was a common problem.


    Thanks for shedding a light on this! I don't have any other midi devices to test the output from Ableton Live, but I suppose that's where the jittery clock info comes from then. One thing less to worry about (as it doesn't noticably affect performance). :)

    Hey Ingolf, good thinking, but as far as I know warping is set for each sample individually so there's no global "warping on/off" setting (only a checkbox to turn it on by default for individual samples). I've been testing with an almost empty Live set that contained no .wav samples anyway. I think it might simply be a general issue with Ableton Live.


    By the way, I've made some progress setting up my Kemper automation method. I've created a virtual Kemper controller that makes automating rig and effects changes a lot easier because it can be programmed directly in the automation lane in arrangement view, whereas the envelopes for directly controlling CCs are buried inside midi clips. And a bonus: my controller has a volume slider that actually works with the nodes-and-lines method like in the image in my first post, which I find much more elegant and precise than having to use drawing mode when working directly with CC#7 (like I described above)!