I'm not sure if it's okay to post gee-whiz module wishes here, but so
far it seems to be, so I'm going to. Be aware that I have no real
understanding of what I'm talking about. If "freshman mistakes" really
annoy you please accept my sincere apologies and just ignore this
message.
Here is one of the modules I'd like but which does not yet exist.
(Actually I want four of them). I don't even know if such a thing can
exist.
The module would be MOTM format, 1U wide, with 4 jacks, three knobs, and
one three-position switch. The jacks would be TRIG IN, TRIG OUT, CV OUT,
and GATE OUT.
TRIG IN would connect to a usual piezo drum trigger, and ideally would
also work with regular audio in (as is the case with the equivalent to
TRIG IN on many analog drum synths), as well as a regular clock in (such
as a square LFO).
TRIG OUT would generate a trigger pulse suitable for a MOTM-800 EG,
MOTM-100 NOISE/S&H, or other input that makes we Pd programmers think of
a bang. CV OUT would generate a CV based on how hard you squeezed
("squoze?") the piezo (or how loud the audio hit was, assuming that can
be made to happen). GATE OUT would generate a GATE suitable for a
MOTM-800 EG.
The switch would select whether how hard you squeezed controlled GATE
length, CV, and perhaps it might have a middle position in which both
GATE length and CV were so controlled.
The three knobs are SENSITIVITY, GATE TIME, and CURVE. SENSITIVITY
adjusts how much signal you get from the TRIG IN jack. This is a crucial
feature for drum trigger kits, since each drum has a different
sensitivity and it's good to tune them so they're all similar. GATE TIME
is obvious. CURVE controls a response curve that translates how hard you
hit the piezo into how big of a CV and/or GATE you get out. Some like
this very linear, some like it exponential. Exponential CV response
would be especially useful for driving the pitch CVs of VCOs. I have no
idea if this "CURVE" feature is possible.
Obligatory "because this is MOTM" style over-the-top feature, if you're
into that: each of these has ∗rear panel∗ connectors and trim pots for
three others. These are used to utterly cancel crosstalk when the piezo
triggers are mounted to the same physical object. Trust me, drummers
love to calibrate against crosstalk for hours. The more difficult it is
to reach these pots, the better. ;)
Why? Well, here's the reason why this module is so desirable. Right now,
if you want to play synthesized drums, you have two choices. One is
MIDI. The shortest MIDI message is somewhere around 1ms of transmit
time, which is only barely noticeable to a good fast drummer. It's
really hard to keep latency (time between physical contact with the
sensor and sound production) down this low, however. I can produce MIDI
in this much time from a Zendrum or an old Alesis D4, however MIDI then
has to get processed by some sound engine to produce sound, and usually
that phase is not only noticeably long (> 5ms), but non-deterministic.
To me, it feels a lot nicer to play into my sampler at a constant 5ms
latency than it is to play into my FM synth with non-deterministic
latencies from 1-12ms. To a fast accurate drummer unlike myself, either
is unacceptable.
The other choice is to get an SDS-8, drumfire, or some other analog drum
synth. Latency basically goes away, which is wonderful. But, analog drum
synths (at least that I've ever seen) are all heavily normalized.
They're also all out of production.
Applications: connect TRIG and GATE to MOTM-800 for control of synth
voice. Connect TRIG to MOTM-101, Arrick sequencer, MILTON, or other
clocked devices for what I call, to coin a phrase, "rich man's tap
tempo". With GATE width control, could also give "pulse width
modulation" control to the SQUARE output of an LFO. If you ever find
something that pumps out clocks, you could use this to generate
corresponding GATEs. On most drum synthesizers, you can plug plain old
audio into the TRIG IN jack, and it will trigger, so in this way it is
also a kind of "poor man's envelope follower". A passive 1U panel with
four drum triggers on it -- 1" piezo disks sandwiched between squares of
old mouse pad and quick-dry epoxy -- and four jacks, would be nice. That
way you can play your MOTM by thumping on it.
GATE time under voltage control? Nah, I think that should be a feature
of the envelope generator.
Starting point:
http://www.paia.com/drumsens.htm. Honestly if I were
half as good with electronics as I am with software I'd try to build
this circuit, but I'm even stumped immediately by the power connector.
Seriously. Someone should take this soldering iron away from me before I
start to think that I know what I'm doing.