DIY A2E Cymbal 3 Zone - Switch/Choke False Trigger

[alexmcintosh]

I'm getting switch triggering on a cymbal, when I should not be getting anything.

Here's the details: I have built an A2E (Acoustic to Electric) Cymbal. I have one Piezo attached to the bow. I'm using 3.5mm cable. And have a 'Female Jack, 3.5mm, 4 Conductor' jack on the cymbal that it all goes into.
For the TMI (MegaDrum) I have the bow = Piezo, and the Edge = Switch.
The problem is that I will get a Edge hit when I give the cymbal a good whack, even when the switch is not hooked up; so I'll disconnect the switch and there is just a wire hanging from the jack on the cymbal. If I physically disconnect the wire from the Megadrum input, then the hard whack doesn't trigger an edge trigger. This tells me that the problem is located on the cymbal itself. Note: I can adjust the settings in MegaDrum such that even normal to light hits will generate the Edge Switch (done by raising the Threshold).
I don't know why giving this thing a hit is generating a signal for the MegaDrum to detect? The only thing I can think of is that the 4 Pole male connector (from the cable) plugged into the 4 Pole jack is jostling around enough that the pole for the switch is somehow getting a bleed through signal from the Piezo pole. I don't know, I'm stumped.

Any feedback is greatly welcome..

[dmitri]

Let me guess. You set Threshold on the edge to 37, right?
Set the edge Threshold to 36? Still getting edge triggering when hitting bow?
Set the edge Threshold to 35? Still getting edge triggering when hitting bow?
...
At what Threshold edge triggering stops when hitting bow?

[alexmcintosh]

Dmitri as always thanks for your expedient reply..
Yes.
Specifically: for a Gain=0 (Retrig=DynLeve=DynTime=0) (3rd Zone = 0's + Dampened Note)
Hits Generate:
Threshold @ 35 = AfterTouch + Dampened Note
Threshold @ 20 = Edge Notes + some Bow Notes
Threshold @ 10 = Bow Notes

Using the Choke (touch choke) Generates:
Threshold @ 35 = Touch Choke= Nothing. Touch Choke+Hit = Dampened Note + AfterTouch
Threshold @ 20 = Touch Choke=AfterTouch. Touch Choke+Hit=Dampened Note + AfterTouch
Threshold @ 10 = Nothing, Choke + Hit = Edge Note

Note: Aftertouch's above are all Bow & 'Dampened Note' Notes

I really like the Choke feature (touch Choke) it's fantastic. Is there a way to make all the pieces fit? Have my Touch Choke & also get an edge Note?

Thanks.. Alex.

[dmitri]

You shouldn't lower Gain on the Switch type Edge input. You should leave it at default 4 or raise it for Switch type Edge inputs.
With Gain at 4 or higher, set Threshold on the Edge to 60. Lower it by 1 until pressing/releasing the edge switches STARTS to generate Aftertouch messages. Note the Threshold level you set as level1.
Continue to lower Threshold on the edge by 1 until pressing/releasing the edge switches STOPS to generate Aftertouch messages. Note the Threshold level you set as level2.
Set the Threshold on the Edge to (leve1+level2)/2.

Also see http://www.megadrum.info/content/settin ... one-cymbal

[angr77]

Dmitri,

Is this guide for all type of Switch based e-cymbals? (is this what the generic function "set all edge swithes" do then you turn it on?)

Best Regards

Angr77

[dmitri]

Dmitri,

Is this guide for all type of Switch based e-cymbals? (is this what the generic function "set all edge swithes" do then you turn it on?)

In firmware it detects only the upper Threshold level and sets it slightly below it. This is why you may need to fine tune it after that.

[angr77]

Aha. You learn something new about the MD everyday...

Thanks!

[alexmcintosh]

Dmitri..
Here are my results:
Edge Switch: Gain=4, Threshold=60, Touch Choke
Touching & Releasing Touch Choke & Lowering Threshold..
Nothing.. (no Output)
Threshold @ 28= Aftertouches Generated Automatically, Touching Touch Choke Stops Aftertouches
Threshold @ 27 = Aftertouches Generated by Touching Touch Choke (LEVEL1)
Threshold @ 14 = no Aftertouches Generated (LEVEL2)

therefor: Switch Threshold = (LEVEL1+LEVEL2)/2 = (27+14)/2 = 20.5
I set the Edge Switch to 20 and 21, but I still get the Edge hits; I've included the Visual Midi Log (Note: 69=Bow Note, 71=Edge Note)
Thanks.. Alex

[dmitri]

This can only mean that the edge switch is intermittently "making" when you are hitting the bow. What sort of a switch are you using on the edge?

[ignotus]

Afaik, he's just using one side of the switch (metal to ring - nothing to ground) and it works like a touch switch with certain threshold settings. I also use it that way, but one strange effect is that the edge will randomly get triggered - when the fact is that the other half of the switch isn't even there, so it's impossible that the switch is "making"... I don't mind because I just set edge note to bow note (crashes are only 1 zone + choke in AD) but I think he wants to get rid of the edge triggers while still being able to use the "touch" choke.