Conference napalm::commusic_v1

2366.0. "Blast from the past: Simmons SDE module review" by RANGER::EIRIKUR (Eir�kur Hallgr�msson) Fri Jun 08 1990 19:07

    Moderators: please feel free to move to a 'odd hardware' note. I didn't
    see a good place...
    
It's time for my overdue review of the Simmons SDE.  Those not interested in
odd bits of hardware history should skip this.  I have now bolted it into
my rack, so it looks like it is staying here.

I find myself in possesion of a Simmons SDE.  It is a one U rackmount module,
six voice FM synthesizer made by Simmons as an expander for their MIDI
percussion systems.  While it is intended (and optimised) for percussion use,
I'm finding uses for it in my largely keyboard and sequencer driven studio.
It has an interesting (and incredibly complex) user interface that reminds me
of some of my Oberheim equipment.  There are six realtime editing knobs, and an
LED per channel to indicate that it has triggered--a two digit seven segment
LED is used for patch/voice numbers.

It's the most unusual FM synth that I have seen.  It is a 4-operator unit, like
an FB01.  There are, in fact, two Yamaha chips on the board, which is a Simmons
board, not Japanese.

The sound is excellent, clean and noise free.  The short and clean audio path
(TLO84s) probably accounts for this.  I wish I had an FB01 to compare it to.

There are 20 sounds in ROM, and RAM for 20 user sounds, and 20 "Patches," which
are setups that define what voices respond to what channels.  Being percussion
oriented, it doesn't really have a standard multi-timbral implementation.  For
each of the six voices, you can assign a sound, volume, panning, MIDI channel
(and or note number) and whether the MIDI note number should control the pitch. 
It will also do a simple split, where voices 1-x respond to side of the
keyboard and x-6 respond to another--on the same MIDI channel.

While it is intended for percussion sounds, it can make a wide variety of
keyboard sounds if you read the (difficult to understand, English!) manuals.

The most unusual feature is the sound programming.  There is no MIDI
implementation for this at all.  You can't even save sounds to MIDI (a
feature-laden cassette interface is provided for the masochists among us).
The sound programming does not follow the Yamaha model.  Instead, there are six
'templates' (which I assume map to some combination of algorithm and default
values and ???), and set of six knobs.  You thus have six controllable
parameters for each sound, realtime editable, with real knobs.  Most of the
templates define the knobs in similar ways.  The knob parameters are
wide-range, and if you don't like the range provided, you can extend it by
cranking the knob all the way to one end, saving the sound, and restoring it. 
Presto! The knob's virtual position is in the middle.  I'm serious.  Works like
a charm.  I should see exactly how long an envelop I can get this way.

I spent a long time lost in the manuals, confused by the template concept
because there is no way to select a template.   I have finally concluded that
the listing of ROM sounds, including which template is used, is the means for
access to a given template.  You pick a ROM sound that uses the desired
template, play with the knobs, then store it in a user location.  Sounds like
it can't do much, eh?  Well, I have gone from an FM bell sound to an organ, to
a string section, all just with knob twiddling.  I should spend more time with
this thing.

The velocity response is quite strong (and usually controllable with one of the
parameters, Bite).  There is NO response to pitch-bend, portamento, vibrato,
etc.  Drum thinking.

All in all, an interesting white elephant for my collection.  I'm getting an
incredibly nasty distorted guitar sound out of it.

Questions, esp. for the Simmons owners out there:  What is the (entirely
undocumented) audio input for?  I wasn't willing to disassemble the thing far
enough to trace the etch.  Were there ever any ROM/RAM cartridges made?  I
would love to get hold of some.