Mutable Instruments Blinds User Manual

Mutable Instruments | Blinds

Blinds requires a -12V / +12V power supply (2x5 pin connector). The red stripe of the ribbon cable (-12V
side) must be oriented on the same side as the “Red stripe” marking on the board. The module draws
70mA from the -12V rail and 70mA from the +12V rail.

Current consumption can reach 90mA on either rail depending on the color and brightness of the LEDs.

This device complies with part 15 of the FCC Rules. Operation is subject to the following
two conditions: (1) This device may not cause harmful interference, and (2) this device must
accept any interference received, including interference that may cause undesired
operation.

This device meets the requirements of the following standards: EN55032, EN55103-2,
EN61000-3-2, EN61000-3-3, EN62311.

Blinds is a 4-channel voltage-controlled signal polarizer. Each channel consists of a polarizer circuit, also
known as a four-quadrant multiplier. This circuit acts like a VCA, except that a negative control voltage will
cause the output signal to be inverted, instead of being silenced. Blinds’ outputs are daisy-chained,
allowing adjacent groups of 2, 3, or all 4 channels, to be mixed together.

1 of 4

Mutable Instruments | Blinds

A. Channel polarity and gain. At 12 o’clock, the channel is muted. Turn clockwise to amplify, turn

counter-clock- wise to amplify and invert.

B. Modulation attenuverter. Adjusts the amount and polarity of modulation from the modulation input (2),

i.e. how much, and in which direction, the channel polarity and gain will wiggle around the central value
set by A.

1. Signal input. Blinds’ inputs are DC-coupled and accept both audio and CV signals. This input receives

+5V when no patch cable is inserted.

2. Modulation input. This input is also DC-coupled. When audio-rate signals are present on both the

signal and modulation input, Blinds works as a pure ring-modulator.

3. Signal output. When no patch cable is plugged into an output, the signal from this channel is routed to

the next channel. For example, when no patch cable is patched into output 1, output 2 will contain the sum
of channel 2 and channel 1. If nothing is patched into outputs 1, 2 and 3, then output 4 will contain the
sum of all four channels.

4. Gain and polarity indicator. The color corresponds to the polarity (green = positive, red = negative),

the bright- ness to the gain.

5. Output level and polarity indicator.

The following equation describes the operation performed by each channel:

Where Vout is the output voltage, Vin the input voltage, Vmod the control voltage, BigKnob and

SmallKnob the position of the big and small knobs, represented as a number between -1 and 1 (0 being

the 12 o’clock position).

Because Vin is normalized to +5V, when nothing is patched into Vin, this equation becomes:

2 of 4