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#6594 - 08/16/02 05:41 PM MIDI pedalboard
rattley Offline
Member

Registered: 11/14/99
Posts: 834
Loc: Punta Gorda Florida USA
Hello .......... I have been experimenting with a homemade 32 note MIDI pedalboard I made 2 months ago. So far I am pleased with the results and will share any info to anyone who asks. I was trying NOT to spend a lot of money on this project...........I just wanted a working prototype. First I constructed a single octave pedalboard out of unfinished lumber, and experimented around with finding the proper electrical contacts/switches, springs and midi connections. I have admired Kenneth's pedalboard and questioned him on the mechanics of the pedalboard's electrical contacts to the midi controller. He offered some advice, but I chose another direction......................
I used my Conn Theatrette organ's pedals as a guide to the pedal's measurements. I also learned that different organ manufacturers used different spacing of the pedals. You think there would have been a standard!! I constructed the pedals out of douglas fir 1 X 2s and 1 X 3s and stained and varnished the white keys and painted the black keys gloss black. They are all strung on a 48 inch piece of 7/16th inch smooth steel rod. I used highly sanded wooden spacers between the pedals to achieve the correct spacing. I made a housing using 1 X 4s and 1 X 6s to keep the pedal assembly together. The housing is painted black too. Oak or walnut was my first choice, but the cost choked me!! The douglas fir finished product looks very nice.
I wanted simplicity and reliability, so I used simple copper strips attached to wires mounted on the underneath of each pedal back, and the mating contacts on a rail along the bottom of the pedalboard length. Each pedal has an independent steel spring attached with eyescrews. I had to shop around for 3 weeks to find springs that felt right and would last............what a chore! I wanted to use some type of micro-switch or magnetic reed switch.......but multiply the cost by 32....oh well...........I haven't had a problem with dirty contacts yet, but I could easily change to a better contact when and if necessary.
Now the fun part!! ...........I searched for months trying to find some kind of MIDI interface, and I finally realized that I already had the answer in front of me..........a Reveal MusicStar 3 octave mini computer music keyboard I have been using for years. It works off a 9 volt AC adapter, has a MIDI out connection, you can assign MIDI channels to it, You can change octaves too. All very easily too!! I took the thing apart and found how easily they connected the keys to the IC chip. A simple 8 pin connector and a 5 pin connector sent all the possible notes pressed in the 3 octave range to the IC chip. One pin from the 8 pin connector PLUS one pin from the 5 pin connector sounded a note. I just experimented with all the possible combinations using jumper wires with the mini keyboard connected and found the 32 notes I needed. I bypassed the mini keyboard and used 4 8 wire high speed telephone cables as the connecting wires between the pedalboard and midi controller. The front buttons on the MusicStar still function to turn the unit on, change midi channels or octaves.
These mini keyboards are always sold on Ebay...........I have bought several that sold for under $10!!!!!
I've used these for other types of midi controllers too.
I have been extremely pleased with my project. 2 months of daily heavy duty playing has not caused any problems yet. My total cost was under $100 in its construction since I already had some of the parts. I have made 2 more and spent about $125 on each.......but these take many many hours to build. Fortunately these were for friends and I had help in building them. The fun hasn't worn out yet either.
I use my pedalboard with 2 61 note midi keyboards with the SCPOP and still get watery eyes sometimes when I play. The pedal notes add so much more to the 2 other keyboards. Those SCPOP organ sounds are SO beautiful............I wish I could play better....................Thanks to all for your support and inspiration!! If i can find a digital camera I'll post some pix. Best wishes -- CHARLEY

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#6595 - 08/19/02 07:23 AM Re: MIDI pedalboard
Chris Attison Offline
Member

Registered: 12/08/98
Posts: 819
Loc: Long Island, NY.
That defeintely sounds interesting. I would like to see pics of that.
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#6596 - 08/19/02 10:57 AM Re: MIDI pedalboard
Anonymous
Unregistered


I am posting in behalf of MORPH. He told me go ahead, I could use his username. I'm a friend of his and sort of do a bit of wiring around here and a little bit of the non-union oriented technical stuff. I read your posting and must say that it is refreshing to read of creation of hardware. Probably all I can additionally pitch-in are a few ideas with wire, switching, and power supplys.

Power supplies are my specialty and what you can do to prevent 60Hz sine wave bleed into your sound circuits (if you should ever encounter this problem) is to use a switching power supply out of an old computer. You electrolytically filter the low and high frequencies using a serial/parrellel filter pak bridged in-line and across each switching power supply voltage line. The end result: pure Direct Current just as silent as a battery, noiseless (immeasurable noise). Hardly portable, but silent power feeds.

Belden makes a re-flexible triple shielded Catagory 5 cable that I readily use around here for low voltage feeds, switching, and of course, the LAN network. The wire is way under-rated and exceeds performance as far as two full wire classes above it because of its very rich gold:copper content of its ore with the outer plating being 18 caret pure that is garanteed non-breached if not bent tighter than a 10 inch radius. If you have or know someone with a resale number willing to register with Belden, you can order the wire jacketed with color combos of your choice, and they dont charge any extra for color stripes, dashes, dots, or 1,2,even 3 color rings. They do charge for combos beyond that though like dash ring or dot ring color combos. End result: ultra low loss delivery of data, power, and switching.
NOTE: Not good for analog audio signals as it is solid core wire. Also not for higher energy power feed. This is the same wire that would be found in the sub floors at JPL too, even though its one of those who cares secrets like other things at JPL. I know this for a fact because I was the one contracted to put the specified in there many years ago. They don't even want anyone to know the price of a small milk in their cafateria.
Silent switching can also be made by simple FET hybrid-able circuitry capable of .005 to 377 volts at .05, .5, 1, 2, 5, and 12.5 Amps. 25 Amps at 220 volts and 50A at 110V. It is based on a Motorola FET 2N26079 or was it 2N27609? Ugh!...Blaming my parents on that one for long ago when I was a kid.(Parents! Don't let your kids smoke pot.)You can find it in the popular electronics archive. It is a great thing to prevent that popping that is sometimes associated in audio equipment, especially where the RMS voltage can be above .5 volts. The end result: silent switching
thanks,
pete's friend stevo

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#6597 - 08/20/02 02:45 PM Re: MIDI pedalboard
mdyde Offline
Junior Member

Registered: 08/16/02
Posts: 6
Loc: Birmingham, West Midlands, Eng...
Rattley,

There are some photographs of a MIDI pedalboard that I made by similar means on my site ( http://www.hauptwerk.co.uk/ ), which you've probably seen anyway by now. There's also a link to a company that makes them for about US $1000.

Martin Dyde.

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