Studio Electronics Boomstar Modular - Manual (Page 13)

4075 Filter Module
Description
The 4075 filter is a voltage controlled, discrete analog, 24/db/oct cascaded transconductance low-pass filter, employing hand-
matched transistors. In its lowest FREQUENCY setting it shaves off higher frequency harmonics; its RESONANCE or “Q”
circuit pushes those harmonics past the self-oscillation boiling point, projecting a thumpy, thrashing squeal, with explosive low
to mid-range power and depth. The design is actually pulled from the four-pole ARP 4072 (better: more parts and trims), sans
the 12kHz design flaw which hamstrung the original’s high end. The 4075 name has stuck—no correcting our little misnomer.
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Our 4075 filter is the most requested of the Boomstar filter models, perhaps owing to its uniqueness. Has there ever been a
better match for a square wave? It weaves dreams with “glidey,” 70s basslines, is a natural in the lead department, and feels
as if a temper tantrum simmers a mere micron beneath its veneer of faux respectability. Aggressive and articulate, this fresh
ARP can snap punishing kick drum sounds out as well as color with bright, edgy, stringy tones for essential arpeggiations.
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Potentiometer Potential
Seven attenuation pots control the FREQUENCY, RESONANCE, FREQ CV 1, RESO CV, FREQ CV 2, INPUT and OUTPUT,
delivering smooth, detailed, and complex expression.
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Switch It Up !
Classic Minimoog FULL and HALF strength filter frequency keyboard/voltage tracking for rounder low end with brilliant highs.
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Patch It Up
Seven patch points: 1 V/O, FREQ CV 1, FREQ CV 2, RESO CV, INPUT and 2x OUTPUT direct the deepest manipulation.
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AMP 4075 5089 3003
DRIVE
ST 1/2
OUTPUT ST 2/2 ST 2/1
ST 1/1 INPUT
INPUT
OUTPUT
STAGE 2/2
STAGE 1/2
DRONE
FULL
INPUT
1 V/O FREQ CV 1 FREQ CV 2 RESO CV
OUTPUT OUTPUT
FREQUENCY
FREQ CV 1
INPUT OUTPUT
FREQ CV 2
RESO CV
RESONANCE
HALF
TRACK
FULL
INPUT
1 V/O FREQ CV 1 FREQ CV 2 RESO CV
OUTPUT OUTPUT
FREQUENCY
FREQ CV 1
INPUT OUTPUT
FREQ CV 2
RESO CV
RESONANCE
HALF
TRACK
INPUT
1 V/O FREQ CV 1 FREQ CV 2 RESO CV
OUTPUT OUTPUT
FREQUENCY
FREQ CV 1
INPUT OUTPUT
FREQ CV 2
RESO CV
RESONANCE
HALF
TRACK