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I've finally decided to try to make a Yamaha 3 zone replica for my MegaDrum. I'll try to follow Kimouette's version of Elrules version
Here's Kimouettes simplified and modified circuit diagram of the original Yamaha PCY-150s:

And here's a link to some pictures of her building it:
http://picasaweb.google.ca/Kim.Tanguay/AToECymbal3ZoneYamahaReplica#

I'm not really sure I've understood everything correctly. So please bear with me and help me out if you see anything spooky.
I've created a bell switch and an Edge switch made of a thin plastic mat and piece of brass.
Here's an overview: I just laid it out so it would be easier for me to see how everything is connected. The brass parts of the bell and edge switches will of course face the cymbal later and the piezo will be situated under the cymbal.


Bell switch:


Edge switch:


Piezo:


I've read through a few threads both here and at vdrums.com to get the grip of this build.
Here's a good text explaining how it works that I found here in the MegaDrum forum:
"If the edge is hit, the switch closes and the piezo picks up the vibration and produces the assigned sound for an edge hit. This would go the same for the bell. If neither of the switches are closed but the piezo is picking up vibration, then it will produce sounds based on the bow hit. The 10k resistor is used to separate the edge and bell switch. This is done by changing the voltage that it registers across the piezo. For the choke, when the edge is held, MegaDrum will then decipher the switch being closed and not momentary and choke out the sound.

I'm a little unsure about how to interpret the switches. Do I have to ground both the bell switch and the edge switch separately like I've done in my pictures above?. Or is it sufficient to connect one wire from sleeve of jack to the cymbal and that will ground both the edge and bell switch at the same time. Isn't it basically one switch consisting of two switch parts (edge and bell)?

rockdude wrote:I'm a little unsure about how to interpret the switches. Do I have to ground both the bell switch and the edge switch separately like I've done in my pictures above?. Or is it sufficient to connect one wire from sleeve of jack to the cymbal and that will ground both the edge and bell switch at the same time. Isn't it basically one switch consisting of two switch parts (edge and bell)?

I'm quite sure it's in electrical point of view unnecessary to ground both switches separately. I would just connect 1 wire to body of the cymbal.

You can connect switches as you like as long as the ground is connected to both switches (and to the piezo of course).

dmitri wrote:You can connect switches as you like as long as the ground is connected to both switches (and to the piezo of course).

And that's what it will be with only one wire from cymbal to sleeve, right?

I guess so unless the cymbal is made of poorly conducting material.

dmitri wrote:I guess so unless the cymbal is made of poorly conducting material.

Ok, thanks for your answers. I guess it won't hurt grounding it twice just for good measure, but I'll try with just one wire first then

Maybe you've already done that, but since we cant see the pictures in details... dont forget to sand the 2 areas of the cymbal that will be used for the switches! And same thing for the pieces of brass, or atleast make sure there is no coating on them.

And since I haven't been arround for a while, just want to let you guys know that my 3-zone yamaha replica is still working perfectly! Some people on vdrums told me that after a while the copper tape would probably become "worn-out", but it's been couple of months now, and it still works fine!

kimouette wrote:Maybe you've already done that, but since we cant see the pictures in details... dont forget to sand the 2 areas of the cymbal that will be used for the switches! And same thing for the pieces of brass, or atleast make sure there is no coating on them.

And since I haven't been arround for a while, just want to let you guys know that my 3-zone yamaha replica is still working perfectly! Some people on vdrums told me that after a while the copper tape would probably become "worn-out", but it's been couple of months now, and it still works fine!

Thanks for the info Kim! I've already sanded my cymbal, but not the brass parts.
Btw, did you connect a wire to the sleeve for both the bell and edge switch to ground them? I'm not sure when looking at your pictures regarding that. On the drawing it looks like you're grounding both switches with one wire, but in the pictures and text it seems like you've got one wire to ground the bell switch and another to ground the edge switch.
Anyways, thanks for providing the best pictorial and easiest description of how to build this. Without your pictorial I wouldn't understand. I love pictures

I hope you'll be around here in the forthcoming days since I might need your assistance when tweaking everything ones my build is complete. Your settings and experience from this build might be of great use.

You're right to point this out! The drawing is not as accurate as the pictures!
I've got one wire to ground the bell switch and another to ground the edge switch.

If you look at the following picture:
http://picasaweb.google.ca/Kim.Tanguay/ ... 0547929506
You'll notice that there are 2 wires coming out of each switch : one soldered to the switch (Ring) and one soldered to the cymbal (Ground)

I have modified the drawing
http://picasaweb.google.ca/Kim.Tanguay/ ... 1508954210

Great! Thanks for clarifying. Have you tried this design on a hihat too? I'm tempted if I get this first one right.