[sdiy] Multi-voice architecture without CV parameters: mechanical replication of settings?

[cheater cheater]

Hi guys,
it seems bourns has something as well:
http://www.bourns.com/ProductLine.aspx?name=rotary_position_sensors
but this is even better:
http://www.bourns.com/data/global/pdfs/0473.pdf
shaftless potentiometers. It seems you can stack them. all sorts of
resistances, but unfortunately only linear. And it's carbon too..

They also have shaftless encoders if someone's twisted this way.

BTW, bourns have nice turn-counting dials.
This makes me wonder if it would be possible to take a digital
counter, of the style used in casette playback time counters, and
control it with voltage... e.g. to show the frequency of an oscillator
or something like that.
Or maybe this:
http://sensing.honeywell.com/index.cfm?Ne=2308&ci_id=154327&N=3698&la_id=1
They're hour meters but maybe they sell just the analog digital
displays (see what i did there?)

Honeywell also have some nicepressure sensors and hall position
sensors, but the datasheets are not available for the ones I looked at
so I'm not sure if they'd be usable for keyboards..

As far as stackable pots, there's also this thing from alps:
http://www.alps.com/WebObjects/catalog.woa/E/HTML/Potentiometer/Automotive/RK39A/RK39A_list.html
and a bigger 45 mm one.

Novotechnik/variohm also have a (single) hollow shaft potentiometer,
but the datasheet sucks, and it's not 'through hole', which means that
the shaft comes in through a hole, but the hole does not go through
the potentiometer. So the pot could be the last one in a series, but
that's all.
not exactly designed for this, but it seems like it's doable

btw,
those modular pots here that Steve suggested are probably the coolest
ones, unless you need more than 8 units or something:
http://potentiometers.com/select_custom.cfm?session_num=2010040404481984
the 388 and 389 take up to 8 'modules' which means they would be great
for 8-voice synths :-) and there's a motorized version. It even has a
clutch to make it adjustable by hand. Unfortunately it's only up to 4
modules. Maybe they could make an 8-module version, who knows, maybe
it's up to 4 modules only because the motor and clutch are too weak to
handle 8? Maybe they're working on getting a new 8 module version :-)

last but not least, panasonic:

http://industrial.panasonic.com/www-cgi/jvcr13pz.cgi?E+PZ+2+AOK0013+0+4+WW

btw, I noticed that many of those potentiometers are called 'GS' by
different makers. So I wonder why.

Cheers :-)
D.

On Sat, Apr 3, 2010 at 17:23, Steve Galle <stevegalle at me.com> wrote:
> Maybe something like
>
> http://www.potentiometers.com/series388.cfm ?
>
> Probably expensive, but probably less expensive and less trouble than manufacturing some intricate external mechanical linkage. One cool thing you could do with a linkage on the other hand is get fancy and allow for fine tuning of each individual pot... sounds like a nightmare to build and service though.
>
> Steve
>
> On Apr 3, 2010, at 5:45 AM, cheater cheater wrote:
>
>> Hi guys,
>> I was recently considering older synthesizers, such as the SEM, and
>> also other designs where a lot of the settings are not
>> voltage-controlled. One problem many people mention is having toturn 8
>> knobs (in an 8-voice system) to change one sound parameter.
>>
>> I was wondering what ideas you guys had for solving this problem?
>
>