I started using a MIDI controller to manage the EHX. 3-buttons programmed to Start/Stop and Loop Up/Down. You could always program buttons to take you to a specific loop, and some controllers may have that kind of flexibility, but for general usage I think you just want to mimic the buttons on the foot controller that can be bought for the 45000 and then perhaps program in a couple special functions as needed.

You identified one of the problems though. How do you know which loop you are recalling from the MIDI controller? What I did was a little wasteful, but I still have the EHX 45000 controller on the pedal board as well as the MIDI Controller. That is mostly because it provides status for actions and loop #’s. I found it is not just knowing which loop # I’m on, but also the blinking lights for the queuing actions. In fact, I kept the 45000 itself on the board as well to monitor the beat lights. It would have been a good idea to have the 45000 foot controller also show those beat indicators … maybe it wasn’t possible.

For starting a song and setting everything up with one press, you are going to need one of the more flexible MIDI controllers. The 2 best I have tried for this is the Fractal MFC-101 or even better, something from Liquid Foot. For a less expensive option, check out the PEAK stuff. There is a new one from Morningstar too you might look at. For the basics, you want a controller that can assign any sort of MIDI command to a button, not just a controller that banks and sends Program Change commands. Then, if the controller has features for recalling “songs” and sending a series of commands just when you recall the song, you can make use of that. That’s a huge topic and I can only nudge you in a direction, it takes a lot of effort and experimentation.

Muting a track is possible with MIDI (not really soloing, you have to Mute all the other tracks to solo). It is a bit advanced. Muting is the easy part, unmuting requires that you do something to determine the volume of the track when it “unmutes”. Read the docs for the MIDI implementation. Basically, unmuting will return the volume to the fader position of the track, which is fine if you are setting the sliders where you want live. Or, you can send MIDI CC commands to set the volume of a track, and if you do that, “unmuting” will return the volume to the level received by the last MIDI CC command. All in all though, it is tricky to get this set up in a way that is reusable by a bunch of prerecorded songs. I messed with it, saw it in action, and then decided it was too rigid for my needs. If you have everything mixed down though and you just want to control the volume/mute of the mixdown track, that is a little easier to manage.