Michael Calaroso's Minimoog Squelch Filter Trick - Alesis Andromeda A6 Tips And Tricks Manual

Source, as it has smoothed transitions between the points.)

13.8 michael calaroso's minimoog squelch filter trick:

I find that when I'm using the Minimoog for bass tracks, two oscillators is enough. When you add
adding the third, it becomes more of a special effect better suited for drones or accents than a bass
instrument. When I say bass track, I'm talking about the rhythm component that is shared with
drums.
A Minimoog bass track is *much* more effective if you DON'T use near-unison tunings, otherwise
the sound will phase in and out and that ruins the dominant rhythm that the bass is supposed to
accomplish. Nine times out of ten, I will use just two oscillators tuned an octave apart, and
sometimes a fifth above an octave. And the mix levels are always below seven and never equal, if
they're too hot then the bass sound isn't as variable, that overdrive isn't ALWAYS appropriate.
YMMV. I get more flexibility with octave tunings and mix variations than with filter settings.
"TawrusBassPedal" in preset 2 bank best demonstrates this. This is the Taurus preset from the
original Moog Taurus bass pedal that was used to great effect with progressive groups like Rush
and Genesis. The *key* to that sound is unequal mix levels, if they're too close together the sound
will phase in and out. The only way to know this is to read the schematics, because the presets are
programmed with fixed resistors. That's how I was able to nail that sound on the A6 :) Even Moog
didn't get it right when they included a Taurus sound in the Moog Source factory patch, the mix
levels were equal!
Luckily, the Andromeda has the power of flexibility, if you can figure out what you want to do. Like
Mike's Minimoog filter trick.... Mike?
The Moog modular filter and the Minimoog filter both share a common "fault" that separates them
from the rest of the Moog product line (as well as the ARPs, Oberheims, et al): the resonance drops
off as you approach lower cutoff frequencies. Try this test: turn off all VCOs and crank the
resonance (emphasis) to get the filter to self oscillate; while you hold a key, set the cutoff frequency
at zero and move it down to (-)5; as you approach (-)5, the sine wave dies. Do the same test on
any other synth and the sine wave will be there across the entire range. Try it.
Only the Minimoog and modular filter have this "fault", you won't find it on a Micromoog or a Rogue
or the Memorymoog or anything else. Why? Moog engineers attempt to correct this "fault" in
subsequent products but lost that "something" in the process. Even ARP "improved" their infringed
Moog filter (4012/4034/4035 filter modules). Engineers tend to be focused on great specs like
constant resonance and maximum s/n ratio, and they don't always pay attention to how the
"improvement" is affecting the sound.
Bob Moog is an exception, he pays attention to the sound. This is very evident in the Moogerfooger
filter pedal he makes, it sounds very similar to my Minimoog filter. I also had the opportunity to dig
inside one of the Minimoog prototypes, the Model "C" which predated the production Model "D" and
was built from hand-wired vectorboards. The "C" was built in Trumansburg NY when Bob was in full
command. I noticed that the "C" sounded VERY different from the "D", it was colder and the
resonance was not as interesting as the "D". Upon closer inspection of the derived schematics of
the "C", I found that the filter circuit had two critical component differences from the "D"; these
improved the "specifications" of the filter but had a detriment on the sound.
Trumansburg decided that sound was more important, and the "D" filter circuit now more closely
resembles the modular filter but is not an exact duplicate.
If you have a classic Minimoog bass patch with a resonant filter being spiked by the EG with zero
sustain, what is happening is as the EG drops the cutoff, the resonance is decreasing at the same
time. This is directly responsible for the Minimoog's "beef". Try that on any other synth and it won't
sound the same. This has eluded people for years who were trying to duplicate the classic
Minimoog bass sound.
Lucky for us, Alesis included voltage controlled resonance on both filters and that allows us to better
emulate the Minimoog filter behavior. The trick I use on the A6 is to spike the cutoff AND resonance
with the filter EG, so as the filter cutoff drops to low frequencies the resonance also decreases.
There's a patch of mine that best demonstrates this, it's in preset 2 bank and it's called "Minimuge
Bass"; I don't remember the patch number, I'm at work. Look at the modulations going on in filter2
and you'll see that ENV2 is spiking the resonance just a touch.
difference, you'll hear it right away.
I agree that the A6 filter2 is not quite a Minimoog filter, and keep in mind that there are other
Minimoog "foibles" that contribute to its unique sound, such as the passive mixer (not active!) that
So the boys in
Disable it and listen to the