2 H9s controlled by 1 expression pedal

They don't give a schematic, so it's not clear what it actually does.

On an H9, the expression pedal is more TS than TRS, so it may not be suitable.

Hi folks– New to the H9. Laying out the mother of all pedalboards. I'm getting an H9 Max & and H9 Core and am considering how to control both separately with a single expression pedal (Mission Engineering Inc SP-H9). I am considering an TRS A/B box to switch between the two H9s. I assume that won't be a problem, please advise if otherwise. Now, the question is: What about an A/B/Y box, such that I could control either H9 or BOTH simultaneously? I am considering an A/B/Y box made by American Loopers (https://reverb.com/item/4201234-2-way-expression-splitter-selector-control-two-expression-pedals-at-once-or-just-one) but they encourage checking with the pedal's manufacturer to see if it's ok to combine the expression signal patch with a different pedal. Specifically, they state, "This is a simple TRS signal splitter, there is no voltage regulators of any kind. While this A/B/Y box can be used with with expression pedals, it will be up to you to check with the manufacturer of your pedal for the intended use." If anyone out there has experience/knowledge with this, I'd appreciate your input. Thank you.

You can always just chain the H9s with MIDI and transmit the expression pedal over a MIDI CC.  I do this in my rig, one expression, two H9s, works pretty well.  

So- I have a SP-H9, and it is totally passive, so it should work… but maybe unpredictably. The EXP pedal is all voltage driven… so doubling the input voltage might throw off the range of the thing, you know? Like.. when you are on Y-mode…. you hit 100% halfway down the pedal? idk.

(side note for nick- that thing runs TRS because it actually includes a switch that will hit the AUX switch function on the h9)

Another thought…Let me experiment right quick- 

OK it seems like I can fire up my H9 just fine with my SP unplugged.. and when I plug it in it reads the position the pedal is in. So thats fine.

Possible problem… when I UNPLUG the SP (which I imagine would be like switching) the H9 gets some junk-voltage.. and it had unpredictable effects on the setting. Like.. once it set it to 100%. Once it fired the Aux switch. Once it DIDNT. That would be a dealbreaker for me.

That might be the biggest problem with this plan. Midi would be better… and cheaper!

HOWEVER.. if you want a little more flexibility.. and you have a budget .. the DMC-3XL has an expression pedal in.. and would allow youto independently send MIDI EXP values to either or both H9s on a preset by preset basis… not to mention adding 2 aux switches, looper controls…and a whole dual-preset-control scheme.  http://www.disasterareaamps.com/shop/dmc-3xl-gen3

But really- just connecting them via MIDI is probably cheapest and best.

You absolutely do not need any kind of ABY. The easiest way would be to plug the mission into the first h9 expression Jack, then run a midi cable from The 1st h9 to the 2nd.
But if you’re building the mother of all pedalboards I assume there’s some kind of controller, that probably will have an expression in jack that with then allow you to send expression to any midi capable pedal in the midi the chain, The only thing you have to look out for if you use it that way is that they all want a TRS cable, some do not.

New to Forum.  Can’t find how to post new topic.  My problem seems related to this thread.

I have 2 H9s and want to control preset up/down on both with one click and active passive on both with one click.  What is simplest way.  Connect together with MIDI and one can control the other?  Separate MIDI controller to switch both?  Other?

Go into the Stompboxes category and click on “New Topic” to start a new thread. Please do so.

New to Forum.  Can’t find how to post new topic.  My problem seems related to this thread.

I have 2 H9s and want to control preset up/down on both with one click and active passive on both with one click.  What is simplest way.  Connect together with MIDI and one can control the other?  Separate MIDI controller to switch both?  Other?

I haven’t tested this out (so it may not work) but I believe one simple way to do this is as follows:

Connect the two h9’s (a master and a slave) with a midi cable. And …

Select the midi settings that forces the slave up/down to follow the master (midi channel, send up/down command, etc).  When you select the up/down command, you probably want to automatically activate the preset … so that’s actually two commands with one footswitcth tap … there is a midi send command that does both.. 

Obviously, don’t select that if you want to manually activate the newly-changed preset(s).   If activating manually, you probably want to set the master up to also send activate commands to the slave.

Please let us know how you make out.