Continuing in our series about classic
keyboards, the next revelation in keyboards came around
1970 with the Minimoog. During the sixties synthesizers
became popular, but were large heavy units comprised
of many independent modules. Each module served a particular
function such as oscillator, filter modulator etc. To
create sound required the interconnection of these modules
using patch cables, usually many of them. This created
a specific sound but if the sound was to be changed
beyond what the controls on the modules could do, it
necessitated rewiring the patch cords. Obviously, this
was not a big problem in the recording studio, but was
not practical for live performance. It also needed a
pretty good understanding of the individual synthesizer
modules to achieve good results.
Robert Moog developed the Minimoog as
an alternative to the above. He put the most important
synthesizer elements into a portable package and connected
them internally, controlled by front panel switches
instead of patch cords. While this still didn't permit
instant changing from one sound to another, it was a
whole lot closer to it than using patch cords to set
up the sound.The Minimoog had a small 44 note keyboard
attached right to it so really the whole synthesizer
package was there in one small portable unit ready to
plug into a sound system.
do a quick breakdown of the most important Minimoog
controls. On the front panel left side it had three
oscillators which are the raw sound generators. Each
oscillator had a control to set the octave range it
operated in and also a control to choose one of several
waveforms. Each wave form had a different harmonic content
which could be chosen specific to the end result desired,
The third oscillator also could be used as a LFO (low
frequency oscillator) and its output could be directed
to modulate the filter or envelope generator.
To the right of the oscillators was
the audio mixer section. Here is where the output of
the three oscillators could be mixed together in the
desired ratio and there also were controls to mix in
the output of the white /pink noise generator (useful
for percussion sounds or special effects) and an external
instrument input (to process it through the filters
and envelope generators.
Further to the right is the voltage
controlled filter section. The filter control when set
all the way clockwise will pass all frequencies input
to it. As it is moved counter clockwise it progressively
filters out the highs. Two other controls called Contour
and Emphasis also process how the filter's response
Extreme setting of these cause the filter
to self oscillate adding another spectrum of sounds.
The section in the song Frankenstein by Edgar Winter
that sounds like a flying saucer is a good example of
this.The filter can be controlled by the keyboard and
also be modulated by the oscillator so it is able to
add real time filtering to each note played.
Underneath the filter is an envelope
generator. Four controls are used to control Attack,
Decay, Sustain and Release. Any sound you hear contains
variances over time. A drum or violin has a very abrupt
start to its in comparison to a violin where the note
almost fades in. This can be simulated using the attack
control. Turning it further clockwise delays the beginning
of the note. In the same fashion the decay control varies
how long the note takes to get from its initial peak
down to the point that it sustains for a while at the
same level. The release control determines if the note
quickly fades out or stays on for a long time. I should
mention that there is also a separate envelope generator
in the filter section to control the filter's envelope.
Down to left of the keyboard are several wheels and
switches. The leftmost wheel is the pitch wheel. Turning
this wheel up or down from its center position raised
or lowered the pitch of the note being played by the
right hand on the keyboard. This gave the player the
ability to bend notes the way a guitar player can and
was one of the most attractive features on the Minimoog.
A great example of this is the theme from the TV show
Miami Vice played by Jan Hammer. He was so good at this
often you thought it actually was a guitar.
To the right of the Pitch Wheel was the Modulation
wheel. When activated it controlled the amount of modulation
that would be added to the note being played from none
to full on. It gave quite a bit of expressiveness to
the sound because you could go from a plain note to
something wild. A great example of this are the final
Minimoog notes at the end of You're all I Got Tonight
by the Cars.
Next to the Mod Wheel were two switches. The first
controlled decay. When the switch was off the note would
stop when the key was released. When on it would keep
sustaining as determined by the Envelope generator.
The second switch was for Portamento. This would make
successive notes slide in pitch from one to the other.
Its rate was controlled by the Portamento knob on the
front panel. Remember the Minimoog was a monophonic
synthesizer so only one note could be played at a time
and the lowest note had priority so the Portamento would
make the note transitions blend into each other. This
was used a lot by Styx in the Seventies and was very
prevelant on the song Never Been Any Reason by Head
Many digital versions of the Minimoog have been created,
but in my opinion the sound is never as good as the
real thing. Something about the way the sound is created
and filtered by totally analog components is the reason
why you see original Minimoogs selling for $10000.
Of course there is another side
to this. The instrument, even when new, suffered from
tuning instabilities due to the temperature sensitivities
of the transistors of that time. As the transistors
heated up their performance would drift and so would
the sounds they were creating. Several versions of the
circuit were created as time went on and the stability
got progressively better but only to a point. I remember
seeing Head East in the Eighties. The Minimoog was an
important part of their sound. They had a tech on stage
with a strobe tuner whose only job was to keep the Minimoog
in tune throughout the show.
Now fast forward to today. The Minmoog that when new
was unstable is now additionally plagued with aged components,dirty
switches and corroded circuit board headers. If there
is also electronic component failure, some of the components
are no longer available and also it is necessary to
find components that meet the tolerances of the other
components in the circuit or it will not work right.
Interestingly I had two Minimoogs come in my shop from
two different customers two days apart. I haven't worked
on one in probably twenty years so it was a weird coincidence
since I had been planning to write about the Minimoog
anyway and now I had two in front of me. In the first
one I found a loose component, re soldered it and the
unit performed great so I sent it on its way. This unit
was on tour and in use constantly so it had been maintained.
The second Minimoog had been in storage for thirty
years. It is actually the Minimoog used to record the
movie Saturday Night Fever. This unit did not fare as
well. At first it barely produced any sound due to the
amount of corrosion that was everywhere in the unit.
After carefully taking it apart and cleaning it, I was
able to restore all the functions but it would not calibrate,
so it does not play in tune when you change Octaves.
I am still working with it and hope to solve this problem
soon as this Minimoog is a piece of music history.
All in all, the MInimoog has always
been one of my favorite instruments and always catches
my attention when I hear one.
Weiss is the owner and main technician of Steve Weiss
Electronics Inc. He is experienced in the repair
of analog and digital musical equipment. This includes
everything from Vintage Tube Amps and Pro Audio equipment
to Digital Keyboards There is also a guitar repair
shop staffed by some of the areas top guitar repair
techs. He is authorized for warranty work on most
major brands. Steve Weiss Electronics is located
inside of Sam Ash Music at 5460 West Sample Road
Margate, FL 33073 954-975-3390 Ext 272. Steve has
also spent 25 years on the road as a performing guitarist
and is the designer of Primal Guitar amps that can
be seen at Primal
Steve can also be reached at email@example.com