Micro Memories
by Edward Driscoll, Jr.
Micro Memories
The Yamaha CX5M:
The Music Computer — ‘80s Style
These days, recording music
on a PC is a surprisingly
straightforward affair. Once
you master a program like
Cakewalk’s Sonar or Steinberg’s
Cubase, it’s a matter of if you can
dream it up, you can record it. With
programs like Sony’s Acid, you don’t
even need to be much of a musician:
just layer various loops to taste and
you can start making music.
Back in the 1980s, it was a
different story. Back then, we had to
walk barefoot in the snow for miles
— uphill both ways — to get to our
local music store and use stone
knives and bearskins to record our
music. And we liked it just fine,
dagnabit!
Well, no we didn’t because, actually, we had to use the first generation
of mass produced computer music
technology and it was pretty brutal.
Meet the CX5M
A case in point was the Yamaha
CX5M, sold as a complete, modular
music system. It essentially put the
guts of a Yamaha DX21 synthesizer
inside of a CPU with a QWERTY keyboard and MIDI interface. To control
it, the keyboard/CPU had a multi-pin
connection designed to accept a 66-
key music keyboard (the kind with
black and white keys, not ones that
say QWERTY on them — that was
Yamaha model number YK10, incidentally). It wasn’t touch sensitive
and it lacked a pitch-bending wheel,
but it had a decent feel to it.
The computer used a Z80 chip
as its microprocessor and MSX as its
operating system ( www.faq.msx
net.org), which was popular in the
early ‘80s in Europe, Asia, and South
Korea, but made few inroads into
the US.
The DX21 synthesizer inside of
the CX5M was the baby brother to
Yamaha’s enormously popular (and
more expensive) DX7 (there’ll be a
test later on all of Yamaha’s model
designations), which popularized a
new form of synthesis: digital
frequency modulation — FM, for
short. Its pure, bell-like tones
were seemingly used on every hit
record made in the 1980s and used
examples of DX7s can be found in
music stores to this day.
The CX5M didn’t have a dedicated
monitor; instead, an adaptor cable
with an RF output was designed to
be used with a standard TV, much
like the original Atari 2600 and other
early video games. I ended up using
an old 14” turret dial TV for my
CX5M. But that’s okay, the graphics
in the CX5M were no great shakes —
we’re not talking Apple Macintosh
here.
The CX5M’s CPU accepted data
two ways: it had an Atari-like
cartridge interface and Yamaha
produced a variety of cartridges for
the machine (more on those in a
moment). Like older, 1970s era computers, you could plug a cassette
recorder into it. Originally, this was
used simply to save programs and
files created by the user, but a year
or two into the (short) lifespan of the
CX5M, Yamaha released a couple of
tapes to reprogram the CX5M’s synthesizer with new sounds. One tape
was mostly musical instruments; the
other was mostly sound effects.
How Did It Sound?
The CX5M.
MIDI and keyboard outputs.
F
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NUTS & VOLTS
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8
Curiously for a unit
marketed by Yamaha (at
least in the US) towards
musicians and heavily
advertised for a year or
two in music trade magazines, the unit didn’t boot
directly to the synthesizer.
Instead, when first turned
on, it defaulted to a DOS
prompt and the user had
to type “Call Music” to get
into the synthesizer. Great
engineering, fellas!
JANUARY 2005
