Designing a Patchable Modular Synthesizer with Memory
jdm at synthcom.com
Sat Feb 24 08:49:05 CET 1996
On Wed, 21 Feb 1996, Mark Landman wrote:
> Some interesting thoughts I'd agree that it's important to maintain a
> visual representation of your patch, so you can see what your doing. How
> about some type of pin matrix ala Arp and Ems? Easy to scan and digitize,
> almost as good as patchcords for patching and troubleshooting
Statements about patchcords being easy to troubleshoot have always amazed
me. I always wonder if the persons making them have ever used a
modular, and if so, if they have more than 5 patchcords. My experiences
with patchcords are:
1) There's always at least one less patchcord available than you need.
2) Tracing a patchcord thru the tangle of a typical patch is a pain in
3) Tracing a patchcord is likely to unplug something, or change the
connection of something (ie. to a dirty jack) and change the patch.
Patchcords have the advantage of being very tactile and immediate, but
the advantages begin to be outweighed by the disadvantages after you have
more than 10.
Matrices have the disadvantage of requiring a mental translation from the
matrix to the modular panel. Mental translation gets in the way of
Here's my suggestion for a UI (User Interface):
Each modulation source & destination will have a momentary contact
pushbutton w/ LED above it, LOCATED ON THE MODULE IT'S ASSOCIATED WITH.
To assign a mod routing, push and release the source button, then push and
release the destination button. This will patch the two together thru an
internal switching matrix.
To check out the mod routings for a particular source or destination,
simply press and hold that button for a second. All mod points that are
connected to it will make their LEDs blink. Very fast, intuitive feedback.
Visual, as opposed to mental, processing.
As for the pots/sliders, let's face it, motor driven ones are just too
expensive for most of us to even think about using. Here's my
compromise, stolen from the PAIA Proteus I:
Each slider (pot if you prefer) has an LED above it. When the pot matches
what is in patch (computer) memory, the LED comes on. When you recall a
patch, the LED associated w/ a pot is turned off (unless the pot happens
to match the stored value), and turning a pot does nothing until you move
it to match the stored value. Then the LED turns on. You don't have to
reset a pot unless you're interested in knowing its prior value. From
experience, this works pretty well.
Of course, the biggest problem w/ Clive's pie-in-the-sky modular is the
switching matrix. To build a 64x64 (what I consider the minimum useable
number) audio/cv switching matrix w/ 80-90dB of S/N is quite a
challenge. I suppose you could use relays, but I'd be frightened to see
the power bills. Suggestions, anyone?
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