Mutable Instruments Shelves User Manual

Shelves
User manual

OVERVIEW

Shelves is a voltage-controlled signal processor inspired by the EQ section of console channel strips. Just
like many sought-after equalizers, it provides low-shelf, high-shelf, and two parametric tone controls. Unlike
an equalizer, each of these four tone controllers can be swept over the entire audio range; and their
parameters can be freely modulated with control voltages.
Shelves occupies a space between tone-controllers and filters, sometimes achieving sounds reminiscent of a
filter bank. It provides a subtler and less cliché'd way of spectrally altering complex drones or feedback
patches.

INSTALLATION

Shelves is designed for Eurorack synthesizer systems and occupies 16 HP of space. It requires a -12V /
+12V supply (2x5 connector), consuming 75mA from the -12V rail and 75mA from the +12V rail. The red
stripe of the ribbon cable must be oriented on the same side as the "Red stripe" marking on the printed circuit
board.

PARAMETER RANGES

On all channels, the FREQ knob covers the entire audio range, from 20 Hz to 20kHz. This is radically
different from a classic EQ, in which each section operates in its narrow frequency range. Strange things
(positive/negative interferences or phase effects) can happen when two sections overlap.
All the FREQ CV inputs have a 1V/Oct scale and act as offsets to the value set by the FREQ knobs.
On all channels, the GAIN knob covers an attenuation/boost range of -15dB to +15dB. The GAIN CV input
has a 3dB/V scale and acts as an offset to the value set by the GAIN knob. Gains above +15dB cannot be
reached, even by adding a positive CV offset to the GAIN CV input. However, gains below -15dB can be
obtained by adding a negative CV offset to this CV input.
On parametric channels, Q goes from 0.5 to 20.0 from the panel knob, but can reach higher values, up to
1000.0 through external CV modulation.

CONTROLS, INPUTS AND OUTPUTS