4ms Spectral Multiband Resonator Eurorack Module (26 HP)

4ms SMR Overview

Process audio and control up to 6 VCOs with the 4ms Spectral Multiband Resonator, an innovative resonant filter module in Eurorack format. The module can process audio like a classic filter bank, ring like a marimba when struck, vocode, remix tracks, harmonize, output spectral data, quantize audio to scales, and much more.

A striking ring of colored lights displays the frequency of each filter, as well as the levels and current scale selection. The SMR can also control up to six external VCOs with 1V/oct CV for sequences, chords, and melodies. The Spectral Multiband Resonator module ships with a ribbon power cable and mounting screws.

Spectral Multiband Resonator Overview

• At a glance, the SMR works like a normal six-band graphic EQ: six frequency bandpass filters are mixed together using sliders. Resonance/Q is variable, which changes the ringy-ness or width of the bands.
• The frequency of each channel is treated like a note in a scale, and the six bands form a chord. Spin the Rotate knob and the notes circle around the scale, rotating back to the bottom once they ve reached the top. Adjust Spread and the distance (interval) between each note changes. Triggers for up/down motion, CV inputs for sequencing and scale selection allow for flexible control with external modules. Morph, which automatically crossfades between frequencies, together with variable Slew allows rhythmic clocks to drive the SMR as a variable-speed evolving resonant filter.
• At maximum Resonance/Q, the SMR can be struck like a gong or marimba by inputting clocks or triggers. The frequency of each channel is quantized to a scale: beautiful chords, ethereal tones and eerie ambience flows easily. With lower resonance, the SMR can pull out particular frequency bands, and sweep these across the spectrum.
• Two 1V/octave Frequency jacks allow for tracking even and/or odd bands and creating floating melodies over evolving chord bases, or complex percussive membrane sounds.
• Save your settings into one of six storage banks and recall on the fly. On startup, the SMR instantly jumps to the last saved settings. The color scheme of the lights can be adjusted, so if you prefer all white lights on your modular, you can have that (or all red, or rainbows, pastels, etc.)

Basic Functionality

• Six filter channels, selected from twenty active filters displayed on the light ring
• Variable Q (Resonance) ranges from classic band-pass to ultraresonant ringing
• Ring of 20 full-color lights displays the filter frequencies
• Filter frequencies move about the scale using Rotation and Spread
• Rotation spins the frequencies around the scale
• Spread controls the gap between neighboring bands
• Morph creates a variable-speed crossfade when the filter frequencies change
• Lock buttons prevent each channel from changing in frequency (resonance can also be locked)
• Freq Nudge knobs for creating detuning effects or honing in on an exact frequency
• Frequency CV input (1V/octave) for even and odd bands (flip switch selects single or multiple channel control)
• Stereo ins and outs stagger the bands into evens/odds for an immersive stereo field
• Spectral content outputs for each channel (Env Out) allow for vocoding (spectral transfer)
• Fast or Slow tracking speeds for Envelope CV outputs, or selectable Trigger output mode is useful for extracting a beat from music
• Sliders and CV jacks control each filter s level
• Slew switch applies slew-limiting to the CV level jacks, which prevents clicking from clocks or triggers
• Each bank has 11 scales of 20 frequencies/notes each
• User-programmable scales (select octave, chromatic note, and microtonal adjustments for each note in the scale)
• Scale banks for Western, Indian, Chromatic, Microtonal, Equal tempered, Just intonation tunings
• Rotation/Spread moves about an entire bank, or can be limited to a single scale
• White noise is normalized to the inputs, so the SMR can be used without an external signal

Advanced Functionality

• Program your own scale. The frequency of each of the 20 notes can be assigned by setting the octave, the semitone, and coarse and fine microtone. Up to 11 scales can be saved permanently in the user bank
• Adjust color scheme of the LEDs. Pick a preprogrammed color scheme or create your own using the sliders to set Red/Green/Blue values. Custom color schemes can be saved permanently
• Save your settings in one of six parameter banks. Note position, scale and bank selection, Q value, Lock settings and color scheme can be saved and recalled on the fly. On startup, the SMR loads settings from the last saved bank.
• Optional alternative filter type for a more exponential decay when plucked and different timbral qualities. Freq jacks no longer track 1V/oct in this mode.
• Slider LEDs can be assigned to display level for each channel (combination of slider position and CV on the jack) or clipping for each channel.

Controls, Inputs, and Outputs

• Six sliders control level of filter
  • White LED on each slider indicates gain (selectable to indicate clipping)
• Six CV inputs for level of each filter (slider attenuates CV on jack)
• Twenty full-color LEDs indicate which filters are assigned to which channels
  • Color on LED ring match colors of Env Out LEDs
  • Brightness of each LED shows level of each filter
• Q (Resonance) knob
• Q (Resonance) CV jack
• Stereo input and output (divided into even/odd bands)
  • Odd input jack and Even output jack serve as Mono in/out
• Rotate Clockwise and Rotate counterclockwise trigger jacks
• Rotate CV input jack maps any waveshape to a rotation pattern
• Scale CV input jack selects scale from current bank
• Spread knob sets the interval (spacing) between channels
• Spread CV input jack
• Morph knob sets speed of crossfading, rotating, or spreading
• Morph CV input jack
• Six CV outputs follow envelope of frequency content per band
  • Fast | Slow switch selects envelope tracking speed, or Trigger output mode
  • Pre/Post switch selects whether Env Out jacks track the filter before or after the slider attenuates
• Six Lock buttons lock the frequency of each channel
  • Button is lit when locked
  • Turning Q knob while holding a lock button also locks the Q value (button flashes to indicate Q-lock)
  • Lock jack toggles lock status of even or odd channels
• 1V/oct Frequency input jack for even and odd channels
• Odds Switch selects if 1V/oct Freq jack, Freq Nudge knob, and Lock jack control all odd channels (1/3/5) or just channel 1
• Evens Switch selects if 1V/oct Freq jack, Freq Nudge knob, and Lock jack control all even channels (2/4/6) or just channel 6
• Slew switch enables slew-limiting of incoming CV on the level CV jacks (click and pop prevention).
  • The amount of slew limiting is proportional to Morph setting at the time the switch is flipped on.
• Scale Rotation switch enables filters to rotate into the next scale each time they rotate fully around

Eurorack Ready

• 26 HP Eurorack format module
• Maximum Depth: 0.95" (24mm)
• Includes power ribbon cable with 16-pin Eurorack power header
• Power consumption: +12V: 110mA, -12V: 28mA