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[gmeredith]

There's a kit here from MIDI Kits that interests me. It involves 4 ribbon controller resistor strips and an Arduino board, pre-programmed:

http://midikits.net/midi_ribbonx4/midi_ribbonx4.htm

I'm thinking of making a MIDI fretless bass synth controller - what say ye all??

In stock kit form, pressing down on a position on a ribbon controller produces a MIDI note signal out of the board's MIDI out port, for use by a MIDI sound module etc. There are 4 ribbons, so 4 bass strings. Basically it would be played with one hand in stock form.

I would like to customise it a bit to give more of a traditional feel to the playing. I'm yet to get one of these, but reading the specs, I would want to create some set of momentary switches for the right hand that would be used to trigger the notes like a bass player would use their hand to pick the string on a bass, while the other hand presses on the string to select the note. I'm guessing that all that I need to do would be to set a contact switch in series with each ribbon output wire, before sending it to the circuit. That way, you could press down on the ribbon to select the note, but not have it sound until you "plucked" the contact switch.

Regarding these pluck switches, what could I use? It would be cool if I could actually use, say, a pick, to scrape over a surface or bump in an actual picking motion to trigger the switch, like some sort of tube or string-like switch. Does anyone know of something like this??

The other thing I would like is to use longer ribbon pots - the schematics mention 300mm ribbons, but I would probably find this too short. I was thinking of using the 500mm ones that are available. Provided that they are the same final resistance as the 300mm ones (10K ohm) it should work the same??

Any ideas would be appreciated.

PS - there is also a variant here, which uses an ultrasonic sensor to create MIDI volume messages using the right hand. Could also be useful in the scheme of things:

http://midikits.net/midi_violin/midi_violin.htm

Cheers, Graham

[Circuitbenders]

I never even knew these existed in a commercially available form, but it seems they don't any more.
http://uk.rs-online.com/web/p/potentiometers/7081539/
Where were you looking at 500mm ones? I guess its exactly the same thing just with the 10K spread over an extra 200mm.

I think the biggest problem you'll have with any kind of plucking switch is its longevity. On a small scale you could use something as simple as a momentary toggle switch where it springs back to one position after you pluck it, but i can't imagine it'd last very long. Perhaps you should do some research as to what Tom Morello uses on his guitars for those Rage Against The Machine solos.
It seams reasonable to have a switch in series with the ribbon pot output though.

Theres something about that midikits site that always leaves me slightly baffled as to exactly what they are selling. Am i right in thinking each kit is an arduino and a small plug in midi interface board?

[gmeredith]

The 500mm ones, and other lengths, are sold by element14, mouser and other places. Sparkfun, who also sell kits similar to MIDI Kits, sell them also:

https://www.sparkfun.com/products/8681

Arduino - yes they're all preprgrammed arduinos. MIDI kits also allows you to download their source code for some of the kits if you wanted to DIY from your own arduino board