Famous JManWord's (from Vdrums) cymbal triggers discovered!

[gastric]

I've done some reading but not attempt total comprehension at this point since I don't own a module that supports so many zones. But it's my understanding the Raper circuit simply converts the piezos to switches to satisfy the Roland modules. So it looks a little more complicated than it truly is. Some modules can now use piezos as switches natively, such as the Trigger IO. You simply set the input to switch and use the threshold to control what point the piezo activates the "switch" in the module. I can't say how effective it is compared to a Raper circuit.

Also, it's my understanding a single edge switch can provide both choke and separate edge note triggering based on the length of the switch contact. Short contact triggers and edge note, longer contact triggers aftertouch/choke. So you really get a lot of action from that implementation.

What's more important is what implementations MegaDrum can support since it really doesn't matter what Roland supports when you're using a MegaDrum. You have to build your triggers to the module. For a simple 2-zone-plus-choke you can simply stick a piezo in the bell, another on the bow, and use a simple Hellfire choke switch. This uses two jacks on the cymbal would correspondingly will occupy 1 full TRS and 1 half TRS input. Just split the input with a cable so you can use one TRS input on the module to accept 2 mono chokes so you don't squander inputs. I did this with my Alesis Trigger IO and it worked fine with every VSTi I tested with as they all seem to accept a unique MIDI NOTE for choke, though Superior 2 seems to provide better choking via Roland aftertouch than pure choking via MIDI NOTE. It would work fine with the MegaDrum as well from what I can tell.

However, what would be ideal is to be able to squeeze that edge hit triggering in there as well. That way you can get bell/bow/edge/choke. Four events on the same cymbal using (2 piezo 1 edge switch) and the supporting logic in the module.

There's a variation on the Hellfire designed choke where you leave off the separating material on the leading edge of choke switch. This allows an edge hit to deform the cymbal enough to make a fast close of the switch. But a grab of the switch to make a longer close. Hence you get 2 actions out of one switch. That's where the Cosmo "floating arm" was put into play as the floating arm supposedly lets only a really hard edge hit move the cymbal enough to let the arm touch the cymbal and activate the microswitch. But if you can get rid of all of that complexity with a modified Hellfire choke (which is super easy to create and gives a much larger choke area to grab) switch then you're in business. Here's a thread with photos for the modified Hellfire switch: http://www.vdrums.com/forum/showthread.php?t=41409 Roland user confirms the single switch provides choke and edge events.

Educate me, please!

[bribassguy]

Am I just slow but I am not seeing the need for the extra circut... Isn't this the same as say the snare head rim situtation. Just stick some piezos to the cymabl and let the megadrum sort out which is which

[gastric]

I'm certainly no expert. But the Raper circuit is simply a piezo-to-switch converter to satisfy Roland modules requirement of switch-based cymbals. Some Roland modules, but not all from what I understand, can process a single switch on the edge to provide both the choke and edge hits depending on the length of time the switch is closed. In the case of MegaDrum you could possibly use 3 piezos and the 3-way features noted here viewtopic.php?f=3&t=174 to achieve similar results. However, nobody has confirmed that it works yet. Nor do I know exactly how it functions but I'm assuming it can only provide a single MIDI NOTE event to the edge so you could get either choke or edge hits, but not both.

Note that the advantage of having a physical switch on the edge is that you eliminate all crosstalk in a physical manner. The switch simply doesn't trip unless you grab it or activate it in whatever manner you've implemented. A Hellfire switch as he designed it, which is all I've ever implemented, only activates when you physically grab the cymbal tightly to close the switch and complete the circuit. Thus it will NEVER mistakenly activate during normal play. I'm unsure how a cymbal with three piezos on it will function in regards to crosstalk with the MegaDrum.

But I'm freaking anxious to find out!

[elrules]

However, nobody has confirmed that it works yet.

Damn it! i forgot to test that. I was so excited to have all my pads connected that I didn't have any more inputs for the 3way. Tomorrow I will test it

[gastric]

I prodded JMan for details. He still won't divulge the specific components of his edge switch. But it's definitely just a switch on the edge from the information I've gathered. You can see in the Cosmo linkI provided someone actually implemented an actual lever switch for the edge switch, then mounted that to a floating arm of some sort to allow the arm to flex against the cymbal during hits or choke to activate the switch. That's fairly complicated and bulky IMO. But theoretically you can build your own with the following three components.

Bell piezo
Bow piezo
Edge switch

However, you will only get both edge hits AND chokes from the edge switch with Roland TD modules to my knowledge. They provide processing to determine if the edge switch is momentary, or continuous. Momentary is an edge hit and velocity is pulled from the bow piezo. Continuous switch is a choke which is provided via aftertouch to my knowledge. So you can effectively get four events from these three components. Bell hit, bow hit, edge hit, and choke. It's not clear to me yet if MegaDrum supports four events or just three.

Assuming MegaDrum works just like a Roland module (which nobody has confirmed to me via theory or practical testing though I'm prodding Dmitri and ERules to provide that data) then you could construct a cymbal for use with MegaDrum with the following:

Bell piezo
Bow piezo
Modified Hellfire edge switch.Simple membrane-type switch made from sandwiching two pieces of flexible metal with a very thin separator along all but the leading edge. Acoustic cymbal conversions can use the cymbal itself for half the switch (I've done this and it works excellent and error free). This provides the ability to grab it for a choke, or to whack the edge of your cymbal and cause the switch to momentarily engage for the edge hit.

That is assuming MegaDrum supports two separate events for the edge switch you get edge hits AND choke. Otherwise you get one event, either a choke or an edge hit as is the case with a simple module like a Trigger IO which can only provide one MIDI NOTE event for each individual piezo or switch. If you can only get one event I'm not sure if an edge hit via an edge switch with MegaDrum would provide constant velocity edge hits or if it's smart enough to pull bow piezo data for velocity information.

The Raper circuits are used to satisfy Roland modules which require switches and/or reductions in voltage. Don't quote me on the Raper circuits. I'm neither an electronics/electrical nor Roland guru so I'm not exactly sure what the Raper circuit accomplishes technically. But it's basically a piezo-to-switch circuit. Which has no bearing or benefit at all on the MegaDrum as far as I understand.

[dmitri]

That is assuming MegaDrum supports two separate events for the edge switch you get edge hits AND choke. Otherwise you get one event, either a choke or an edge hit as is the case with a simple module like a Trigger IO which can only provide one MIDI NOTE event for each individual piezo or switch. If you can only get one event I'm not sure if an edge hit via an edge switch with MegaDrum would provide constant velocity edge hits or if it's smart enough to pull bow piezo data for velocity information.

MegaDrum is smart enough.

The Raper circuits are used to satisfy Roland modules which require switches and/or reductions in voltage. Don't quote me on the Raper circuits. I'm neither an electronics/electrical nor Roland guru so I'm not exactly sure what the Raper circuit accomplishes technically. But it's basically a piezo-to-switch circuit. Which has no bearing or benefit at all on the MegaDrum as far as I understand.

MegaDrum and the Raper circuit should play along well if you pull the switch input to +5 over 100Ohm-1k resistor. Not tested by me.

[elrules]

Bell piezo
Bow piezo
Modified Hellfire edge switch.Simple membrane-type switch made from sandwiching two pieces of flexible metal with a very thin separator along all but the leading edge. Acoustic cymbal conversions can use the cymbal itself for half the switch (I've done this and it works excellent and error free). This provides the ability to grab it for a choke, or to whack the edge of your cymbal and cause the switch to momentarily engage for the edge hit.

I have built my cymbals like that, but with sandwitching also on the bell side. I have one piezo at the bow, and two switches, made of aluminum paper films that you can grab or hit with sticks. And it works quite well with megadrum. THe only thing I have not tested yet (because of my holydays) is the 3way feature, that allows megadrum to connect the two outputs of a roland-style cymbal to it like roland does, that is: bow/bell input and bow/edge input, and then trigger only one of those events at a time (bow or bell or edge)

PD: by the way, dmitri, how about a beta-test firmware for the trizone yamaha cymbals? I can test it for you and we can communicate via email the results. I want to actively help megadrum improve, and the only way I can do it is being at your entire disposal for testing that feature, as I own a trizona yamaha cymbal.

[gastric]

Well, as far as I can tell based on my reviews and testing we should be able to construct a functional 4-function cymbal with 1 bell piezo, 1 bow piezo, and a switch at the edge. The trick is constructing a switch that can react to both an edge hit as well as a grab. The VDRUM forum shows one user simply using a roller lever microswitch with mention of a floating arm. You'd have to construct the floating arm in such a fashion that it reacts only to edge hits and grabs and not casual bell/bow hits.

I'd think you could use a piezo as well, but it'd have to be extremely un-sensitive to coexist with both a bell/bow piezo and not simply react to those triggers on accident while still triggering on edge hits and grabs.

The 2-function edge triggering would certainly seem to be the most difficult part.

Not so difficult if you don't mind having a membrane-type switch on TOP of your cymbal that you physically hit with your stick. More difficult having something totally functional and mounted purely under the bottom of a converted acoustic cymbal like JMAN does.

[elrules]

I have now all the materials needed to build my acoustic converted cymbal with the microswitch edge sensor.
Hope I can have time this afternoon to finish building it and post here some photos of the process.

(I am so bussy I haven't had time to do a lot of things I have planned. Remember I said I would post a video showing my megadrum. )

[dcho]

ooh, take lotsa pics! I've got some pintech practice cymbals I'm going to convert at some point and learning to do 3 way triggering would be great. Thanks!