A means of generating a control signal based on how much pressure is applied to the keys of a MIDI keyboard. Most instruments that support this do not have independent pressure sensing for all keys, but rather detect the overall pressure by means of a sensing strip running beneath the keys. Aftertouch may be used to control such functions as vibrato depth, filter brightness, loudness and so on....
Oberheim MX
THE TROUBLE WITH SAMPLE playback synthesizers is that after a while they all start
to sound alike. Yeah, it's great to have hundreds of waveforms to choose from, but how
many sampled bass guitar harmonics and Hammond organs with distorted Leslie can a
musician use? Because manufacturers have relied on the waveforms themselves (and
on built-in effects) to give synths a good sound, the features that make an instrument
expressive and unique have often gotten stripped off before the finished product made it
out the door.
What kind of features? How about knobs that you can twist in performance if the spirit
moves you? How about an open-ended modulation matrix and a couple of extra LFOs
and envelop^, so you can program sounds that have your own personality stamped on
them? Didn't synthesizers used to have those things, once upon a time?
Sure they did. In recent years only the Roland JD-800, with its full complement of front
panel sliders, has come close to capturing the hearts of those who yearn for the good
old days of analog synthesis. Oberheim Electronics is making a bold bid to trump
Roland's ace with their new OB-Mx, a rack mount analog synth that is not only
polyphonic and programmable, but also has a host of modulation routings missing from
the JD-800.
The OB-Mx is sort of a Cadillac of analog, embodying some advanced synthesis
concepts from the good old days and putting them under up-to-the-minute MIDI control.
It includes both Minimoog-style and Oberheim filters, enabling the programmer to
emulate a wide range of classic sounds. And because the two filters can be run
simultaneously in parallel, you can create layered timbres that were previously available
only on a modular analog system.
The OB-Mx is "modular" in a slightly different way. The basic device, including the 5-
rack-space front panel, memory, and a twovoice card, costs $2,150. More voice cards
up to a total of six, for 1 2-note polyphony can be plugged into slots in the chassis. They
cost $769 each, so the fully loaded instrument that we had for review retails for a hefty
$5,995. Ouch. But if you gotta have that sound, consider that what you're paying for are
discrete voice boards with true analog filters, envelopes, and VCAs, not clever
imitations engineered onto a single chip. Compared to what a Prophet-5 cost in the late
'70s, the OB-Mx is still an excellent deal.
How does it sound? Amazing. Big fat bass, rich swirling pads, cutting leads, and special
effects to die for. The multitimbral layered patches will move mountains. Admittedly, this
type of synth inhabits its own sonic universe. If you put the OB-Mx in a rack next to a
digital wonder-toy and switch back and forth, you'll notice that the OB-Mx lacks a certain
sparkle and snap. As you settle into its sound, though, and spend a little time with it, the
strength of analog synthesis becomes clear. The OB would definitely shine as a solo
instrument for the retro tech-no artist who scorns the digital sound, and could also add a
vital new color to the hybrid racks of players who have more wide-ranging needs.
Engineering on the OB-Mx was completed under the direction of fabled electronic
instrument designer Don Buchla, whose first modular systems appeared in the mid '60s.
The Buchla influence can be seen in the open-ended design of the OB-Mx voice, with
its powerful envelop and modulation routings, and also in the fact that some features
don't work quite the way you'd expect them to. It's ironic that after all these years
Buchla, who steered clear of the first frenzy of mass marketing when synthesizers took
off in the mid '70s, has now designed a product that says "Oberheim" on the front panel,
while neither Tom Oberheim nor Bob Moog can put their own names on their new
products.