Re Mixturtrautonium

[Dr. Jörg Schmitz]

Using only the finger for getting the CV with the String
will lead to several other problems :
Dirt and so on will also be on the constantan-wire on the string.
And with each portamento you perform (gliding with the finger
on the string) you will put more and more dirt on it.
Your finger also produces fatty substances, which, accumulated
on the string, will decrease the current.

Another problem : the Bandmanual used in the mixturtrautonium,
is also moveable downwards, to express loudness.
This is a very sensitive method to play this instrument and is
a very important point, playing with the instrument.

Answer to another question (string wiring): 
I wired one by myself. But there is a string-manufacturer in Germany,
who does this for you, if you send him the constantan-wire. The second
string in my instrument is done by this guy, and it is much better.


PS:
I just started to write a homepage in geocities, The following
will be published soon (with schematics)

In the meantime, there are no more theoretical problems
with the subharmonic device,
and it works very well :
I use an integrator with a fixed Voltage input.
The capacitor is shortcutted via a 4066.
The 4066 is triggered by a 4024 divider, which is resetted
by a 16-channel Multiplexer-demultiplexer.
Then i use the Reset signal (modified to a short Voltage peak
by caps and diods), provided by the Multi-demultiplexer for
the 4024 to trigger the 4066.
This leads to a very simple design with free "programmable"
1/n sawtooth generating frequency divider.
The outgoing signal amplitude then must be increased,
depending on the n. (As longer the integrator works before
resetting, as higher the amplitude will be)

With this design, 1 VCO with 3 subharmonic generators
will fit on a 14 x 8 cm board.
6 of those units, together with VCA's, VCF's and so on,
and you will have a nice "extended" Mixturtrautonium.
(extended, because the original instrument does not have VCF's,
for example. Only static filters).

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