Kimouette’s case (A to E conversion)

[kimouette]

I’ve been posting a lot of question for the past 2 weeks. And here is the closest thing to a conclusion I can post!

Yesterday I bought an old acoustic drum for 200$. It’s a Tama Royalstar that includes 8 parts (snare, 3 toms, bass drum, 2 crash, Hi hat)

Now I’m planning to convert it to an electric drum (I should be starting the modifications next week), but I have a very VERY small budget for this! So I’ve been gathering a lot of different suggestions from different people and here is the result :

The drum module

The drum module will be a http://www.megadrum.info/faqs.php#Construction triggered by piezo elements

To convert the USB output of the Megaboard into MIDI signal I’ll be using http://www.steim.org/steim/junxion.html

The snare, the bass drum and the 3 toms

They will be modified using the procedure http://www.picturetrail.com/gallery/view?p=999&gid=9042765&uid=2981932

Except for the Roland cone, I will build them myself using http://vdrums.com/forum/showthread.php?t=21509

For the piezos, I’ll be following http://edrums.info/acoustic_3.htm

For the mesh heads I’ll be doing http://edrums.info/5.htm

The 2 cymbals

They will be modified using http://www.toontrack.com/forum/tm.aspx?m=46574&mpage=1&key=&#46574

Except that I’m not gonna use the Ikea PANNÅ place mat (I’ll find some other kind of cheap material instead), and of course I wont be needing whats listed for the box (using a Megadrum board involves no box and no jack, I’ll simply be wiring my piezos to the analogue input of the Mega board)

The hi hat

This is where I’m stuck!!
For the Hi hat I first thought of using Pfozz technique again, but if I dont want the HH pedal to be useless I dont know what to do : how and where to place what kind of piezos, how to avoid an excess of vibration without just building some kind of new Hi hat from A to Z!

Any help on this issue would be appreciated!
And of course, any suggestion or warning about the different procedures I mentionned would also be very helpful!

Thanks everyone!
Kim

Topic

[gastric]

I see you’ve been getting some help on the MegaDrum forum. That’s good. Note that the MegaDrum can theoretically support whatever features you want. Piezos, switches for chokes or triggers, combination thereof. With up to 32 TRS inputs per MegaDrum the skies the limit.

As far as cymbals. You should have no problem sticking 2 piezos on each cymbal (one on the bell, another 1/2 way between edge and bell for the bow sound) and some sort of a choke if desired. I’m not exactly sure what choking capabilities the MegaDrum has. But a simple Hellfire-style choke like I’ve implemented would definintely be cheap ($16US or less to put a choke on ALL of your cymbals) and no problem for the MegaDrum. The Roland modules can take it a step further and compute that a quick switch signal is an edge crash and a long switch signal is a choke. Unsure if MegaDrum can do that, but if so that’d be fantastic and another arrow in it’s quiver over the Alesis Trigger IO. That might fall into the “3-way-ride” category that is currenlty unconfirmed as working properly for MegaDrum.

For the hihat you can simply stick one piezo on the cymbal, wire that to an input on the MegaDrum. Just like any other trigger. Separately for the hihat you need some sort of pedal. It can be a simple on/off switch of which you can make basically anything you want. Switch on the pedal. Switch on the cymbal. Switch on the hihat stand. Switch in your shoe. It doesn’t matter in that case as it’s a simple on/off switch. You just need to provide some method for the positive and negative of making a contact to complete the circuit. And in fact can literally use two wires, glue them to the stand/pedal somehow, and just construct it in such a fashion that they touch when the pedal is all the way down to trigger the closed. Postive on the bottom edge of the top hihat cymbal, negaive on the top edge of the bottom. Cymbals close, complete circuit, viola! Or for that matter use the entire cymbal as part of the circuit, assuming you didn’t dampen them on the inside. Connect wire to top cymbal, another to bottom, when they touch it completes the circuit. Might not be as successful using the actual cymbals as if you’re hitting them while closed they could bounce around and break the connection causing choppy closed sounds. But it was a thought. 🙂 Get your gears working on a possible solution.

However, the most ideal method is to rig a 25k potentiometer (check the MegaDrum forum for the most appropriate pot to use, but 25k seems fairly universal to most modules) to the hihat stand. You can find the Beatnik method of sticking a slider in a project box, then connecting the slider to the hihat chain on the low end and a spring/rubber band on the hi end to provide automatic return. Wire that to a mono jack, connect that to the pedal input on the MegaDrum (or any brain/controller) and bam! A variable hihat pedal to provide your opens, closes, and everything in between. Shouldn’t cost much more than constructing a simple on/off. Certainly well under $10US total for a totally variable hihat pedal and probably a worthwhile expenditure as on/off hihats are fairly annoying.

Christopher Graham

[kimouette]

Hey gastric,

About the petentiometer…
What range of resistance and what tolerance should I be looking for?

Also, since there are 122 potentiometers available at my electronic store, I’m still wondering what aspect that potentiometer must have in order to be used the way you describe it.

https://www.addison-electronique.com/catalog/advanced_search_result.php?keywords=potentiometer&x=0&y=0

[gastric]

I’m not an electronics guy so I can only tell you what other people have listed for their projects. Here’s two different parts for you to review. I’d think the 25k would be fine for MegaDrum. 30mm of travel is the total switch travel, so you’d have 30mm or less of total hihat/pedal travel from fully open to fully closed. Sounds like a lot but it’s not. I’m in the final construction phase of my own, just short a return spring to pull the slider back to fully opened. There’s not a whole lot of room in my project box so I need a very small spring with a lot of coils in order for it to work properly.

I actually thought the most ideal installation would be in between the two HH cymbals, then you’d never see it, and wouldn’t need a project box at all. Somehow mount the slider body in there to the bottom HH cymbal so it’s stationary, then attach/link the slider arm to the top HH cymbal or the plunger pole the top HH is attached to to provide the movement. No wires, springs, etc. necessary as the actual HH movement would totally actuate the slider. My problem was brainstorming a method of installation that wasn’t totally permenant, allowed the HH to be removed from the stand easily, and yet was strong enough to withstand long term use without coming apart. You could probably just epoxy the slider body to the bottom HH cymbal and construct some easily-removable linkange to the plunger pole that way it’s not physically connected to the top HH cymbal which is where you’d get into problems with the easy-to-remove part.

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Christopher Graham

[gastric]

BTW here’s the Beatnik mirror that is really the basis for the vast majority of the DIY edrum stuff. Tons of excellent, detailed, information full of part #’s, step-by-step instructions, and great photos.

http://www.derksens.com/Beatnik_mirror.htm

Christopher Graham

[Author]

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