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Hi all,

Before I fried my megadrum (see seperate post) I was working on a two way cymbal trigger with choke. Based upon readings from this and other forums, I did a simple two piezo set up, which seemed to function "ALMOST" correctly.

The edge sound worked if both piezos were triggered... the choke worked on the edge piezo... BUT, the bow only worked if struck in isolation..otherwise I would get intermittent bow and edge sounds.

I am unsure how to resolve this as I cannot isolate the two piezos as they need to be linked for the edge sound, but the link is causing problems with the bell. I can no longer find where I read about this simple approach (all I can find now are solutions with a separate switch, or a raper - I think - circuit).

Is there an easy way around this.... is it covered elsewhere here and I missed it ???

Any help much appreciated, though obviously is not that urgent given my megadrum's demise.

Now that my megadrum is back in action I will soon be resuming work on my 2 way cymbals...

Whilst I am sure, given time, I will be able to track down some info pertaining to my original question, I would still be grateful for any info, pointers, or links that anyone may be able to provide on the subject.
Thanksin advance.

Hi,

my DIY cymbals are piezo/switch construction because I was sceptical about if the choke would be working with piezo/piezo (even with keith raper circuit). I use to play chokes very often.
So it's cool to hear that at least choke did work for you, and I am very interested in how your story continues! And also, of course, if others can report about their piezo/piezo (either simple or raper) construction and how it works with megadrum.
If you are going to find a way to get it working correctly, building two way choke-capable cymbals would be a breeze!

You should be able to use a piezo on the bell, piezo on the bow, and switch on the edge. Depending how you construct the switch it and configure MegaDrum it should be able to provide choke only, or provide both choke and edge triggering. Here is a good choke-only switch which is cheap and easy to construct. You can modify it by not building a spacer along the front edge to provide edge triggering on hard hits, though I haven't done that personally. http://www.hellfiredrums.com/archives/67

gastric wrote:[...]it should be able to provide choke only, or provide both choke and edge triggering. [...]

Yeah, but it would be more interesting to hear of real life success stories rather than what one 'should be able' to achieve.
You also cannot deny that a simple 2 piezo cymbal is a much more simple construction than a DIY membrane switch (although the latter is absolutely doable -esp. with your link, thanks!-, even I got it built ).
If a simple piezo/piezo would be working fine with Megadrum, supporting accurately 2 way triggering and choking, and without the need for a bell trigger, this would be perfect: Being able to build a dual zone in 10 minutes instead of 3 hours (which it was for me when building the switch)

There is no issue building a simple 2 piezo cymbal. Just not a piezo on the bow and another on the edge. There's simply not enough physical isolation assuming you're talking about two bare 27mm piezos. You'd have to put one on the bow and another on the bell. Wire them to a TRS, stick them to the cymbal, make some module parameter edits, and you're done in just a few minutes. From my experience the further towards the apex of the bell you place the bell piezo the better isolation it will have from the bow hits. But it shouldn't be an issue with MegaDrum based on what I've read.

But I don't think that's the functionality CairnsFella is looking for.

It sounds like CairnsFella wants a 3-zone cymbal with 4-triggers.

* Bell
* Bow
* Edge hit
* Choke

This has been discussed in the following threads.

viewtopic.php?f=3&t=174
viewtopic.php?f=3&t=286
viewtopic.php?f=3&t=293

I've yet to see an implemented and successfully tested solution documented here. However, using a modified Hellfire type switch should be usable assuming you can get it to actuate the switch successfully and consistently on edge hits. That's supposedly exactly what this Vdrums user is reporting here: http://www.vdrums.com/forum/showthread. ... easy+choke Which is effectively a modified Hellfire switch simplified further by using the acoustic cymbal as half of the switch.

I can confirm the Hellfire switch works beautifully as a straight forward choke. I implemented them on my previous DIY build and they work flawlessly. But I've never had a module that can support choke/edge triggering like a Roland or MegaDrum so I've never personally tested one for edge triggering.

Lastly, there's this Vdrum post where someone basically uses a Hellfire type switch on TOP of their cymbal which should guarantee edge triggering since you're hitting the switch directly. And it's not that unsightly even on top of an acoustic cymbal, at least based on the photos. In regards to the Yahama design which uses a bell/edge switch and single bow piezo you could use the Hellfire type switch on the bell as well, though I'd think you'd need 2 smaller circular ones to prevent the curvature of the bell from forcing the switch closed during application on the cymbal surface. But I'm just saying it would theoretically work.

Hi all.. and many many thanks for the replies.

It is probably fair to say that my "amateur" status is not helping to make my requirements clear.

Rather than state the number of zones I am after (though I believe it is only two.. and I believe gastrics comment on the set up I dont want.. is in fact the set up I want, and indeed it is the isolation problem I am having which, perhaps, is unresolvable) I will try to explain specifically my goal and achievement so far more clearly.

I would also point out that I had seen this "somewhere" but cant recall where.

Basically I want to use just two piezos.

I currently find that attaching them to my 'cymbal" which is basically two pads at present - if I play 'pad one' it works fine which seems to be as a result of receiving signals on both piezo's. If I play 'pad one' then grasp 'pad 1" I get a choke, but if I play 'pad two' it will only intermittently work. Instead usually plaing the saound as per 'pad one; because a signal is received at both piezos, or it stutters between the two sounds. If I isolate 'pad two' it works, but then pad one will not work because it appears to need signals from both piezos.

So in summary. I need a way to trigger both pads for a 'pad one' sound, but to have 'pad two' ignore the 'pad one' sound, if it is the stronger signal ???? Make any sense ??

Of course an alternative simple solution would be equally great.

I will in the meantime look at the 'switch' mentioned above. Thanks again.

Show us your cymbal. I wonder how good mechanically piezos on your cymbal are isolated.

CairnsFella - It sounds like "pad1" is your edge piezo and "pad2" is your bow piezo. Just to confirm, you want a bow sound (big flat part of the cymbal), edge hit sound (very edge), and choke (grab the edge with your hand). If so then that's exactly what I said except no bell sound and the answer should still be the same.

Basically the problem is that the edge piezo is too sensitive and is getting triggered all of the time, thus preventing your bow from being triggered in isolation. I'm not sure you'll be able to get a raw piezo on the edge to function properly due to lack of physical isolation. Maybe if you used a really, really small edge piezo that was extremely un-sensitive (add a bunch of resistors?). If you can't accomplish that consider experimenting with an actual switch on the edge as it provides excellent physical isolation since it doesn't get activated unless directly struck.

dmitri wrote:Show us your cymbal. I wonder how good mechanically piezos on your cymbal are isolated.

Dimitri,

My cymbal is really just a couple of home made pads on one frame, and as yet it is in kit form as I am builing it in in line with whatever functionality might works. They are not - as you correctly imply - well isolated, however, this has been my point i.e. that to get one of the sounds I need to register a hit on "BOTH" piezo's... so I cannot actually fully isolate both.

It strikes me I am barking up a non exitent tree here... I think I will have to take on board the comments gastric has made, and will probably go the switch route for now.

It just seems a shame given that it so nearly works using the simple approach I tried. Perhaps as I learn more I can return to the first idea... you never know I might have a breakthrough one day.

Thanks again all for the input.