dingebre

Joined: Aug 10, 2008 Posts: 270 Location: Salt Lake City, UT USA
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Posted: Tue Apr 17, 2012 7:53 pm Post subject:
Duophonic Keyboard module done! |
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For me, this is the icing on the cake. The first module I built when I first met Nyle and started my project in the mid 1970s was the keyboard. It's somehow fitting I think that the Duophonic Keyboard is the last module for my Synthasystem.
There are pictures on the blog, here: http://analoguerealities.blogspot.com/
I decided on using COTO 9000 series, high sensitivity coil, reed relays to mimic the old Pratt-Read buss keybeds. The high sensitivity coil only draws 5 mA at 5 volts, just right for the Doepfer MTC 64 MIDI to TTL unit. Basically, the MTC 64 takes a note on/off and generates a unique TTL level voltage for that key, and that key alone. So, you turn a MIDI keyboard into a device which can control 64 other things with a single key press. For this module, the MTC 64 turns the relay matrix into a buss type keybed, perfect match.
The blog has more on the features, etc. Let me know if anyone has questions.
Here are a couple of photos.
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This is one of two relay PCBs. I had to split them into two due to the size of the relays. |
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1.24 MB |
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685 Time(s) |
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This is a side view of the module. You can see teh MIDI cables going into the MTC64, the two relay PCBs, and the Duophonic PCB on the bottom. To do over, I would flip the Duophonic PCB 180 degrees and maybe put it on top. I think I will rotate the trimmer |
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1.13 MB |
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688 Time(s) |
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This is the front panel. The Scale and Tune set the keyboard V/Oct and overall tuning (like the frequency knob on a VCO). The Range shifts the tuning by 1 octave per click. The Protamento adds glide between keys, a constant rate. The pitch bend bends the |
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1.06 MB |
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665 Time(s) |
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_________________ David M. Ingebretsen, M.S., M.E.
Collision Forensics & Enginering, Inc.
dingebre@3dphysics.net
http://www.xmission.com/~dingebre/Synthasystem.html |
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