[sdiy] DIY Optical organs.

[Oren Leavitt]

I remember those! A freind of mine found an Optigan with several disks 
in a thrift store about 20 years ago.

Yes - there's tons of technical info here:
http://www.optigan.com/archives.html

One option for reducing the pixel plague might be to make a large 
print-out of the tracks and then photographically make a reduced size 
negative copy on transparent film.


CCartCat at aol.com wrote:

>You've checked out www.optigan.com?  Dunno how much tech info's there, but 
>worth a look.
>
>HTH,
>Kevin Seward
>
>
>In a message dated 1/27/03 7:20:41 PM, philgallo at attglobal.net writes:
>
><< What where the original spec's for the optigon?
>
>
>Was it linear velocity or did the higher notes encode in the smaller
>
>diameter portion of the record surface?
>
>
>Your "Tube" idea sounds "conceptually" like a Mellotron since each recording
>
>is of equal length (but with no spring return).  And since no spring return
>
>how will you control rotation (assuming an "attack" "sustain" and "decay")?
>
>Or does the "ORGAN" part mean "bang yer on" "bang yer off"?
>
>
>Since the original "records" where "printed" they were not "pixelated" but
>
>continuous representations.  Would you OPTO integrate the "BEST QUALITY"
>
>printing into an essentially linear reproduction?
>
>
>The optigon records i remember had pattern percussion which i thought was
>
>also on the record.
>
>
>interesting project, basically an analog sample playback system.
>
>
>regards,
>
>p
>
>
> Hi.
>
>I'm a fan of the old optigan organs, and after despairing of finding one in
>
>Wales, have decided to have a go at building one. The principle looks
>
>straight forward, and I can code a little, so I think I can make something
>
>similar using a computer to generate the tracks.
>
>
>Rather than attempting to make circular records, I think it will be possible
>
>to print the waveforms onto transparent acetate with a laser printer, and
>
>roll the resulting sheet around a clear plastic tube about 6" in diameter.
>
>
>I will then put the light source inside the tube, use a motor to turn it,
>
>and use a single hand held photocell to select the tracks.
>
>With a 1400 dpi printer I reackon I could get about 2 seconds of 7k
>
>bandwidth with a pretty low amplitude resolution with about 10 tracks per
>
>sheet.
>
>
>Anyone tried laser printing waveforms onto acetate? I'm not expecting hi-fi
>
>results. :)
>
>I guess the only way is to try it, but I would be interested to see if
>
>anyone else has had a go, and if they had any advice.
>
>This list looks like a good place to ask! >>
>
>

-- 
Oren Leavitt
oleavitt at ix.netcom.com