Mixing & Output

Stereo Mixer 8

Eight mono channels into a stereo bus, with constant-power panning and per-channel mutes.

What is a Stereo Mixer 8?

A stereo mixer is the workhorse of any patch with more than one voice. You have a bass VCO, a lead, a pad, a kick, a hi-hat, an FX return - by the time you are making a real piece of music, the rack is producing five or ten or twenty separate signals, and they need to become a single L/R pair before they reach the Output.

At its core a mixer is just summation: it adds many input voltages together. What turns a summer into a *mixer* are two things: a volume control per channel that scales each input before it joins the bus, and a pan control that decides how much of that channel goes to the left bus versus the right bus. The math is small; the musical consequence is enormous - mixing is where a stack of monophonic voices becomes a stereo arrangement.

Mixers in the modular world come in many sizes - 4-channel performance mixers, 8-channel mixer-utilities, full 16-channel desks with sends and returns. They share the same architecture: per-channel fader, per-channel pan, often mute, all summed to a master section with its own volume and pan.

Our Stereo Mixer 8

Webrack's Stereo Mixer 8 is 24 HP with 8 mono inputs, each with a fader, a pan knob, and a mute toggle, plus a master Master fader and M.Pan for the whole bus. It outputs to a stereo L / R pair that you typically route into the Output.

Panning is constant-power (cos/sin law), not linear, so a sound centered at 0 is exactly as loud as the same sound hard-panned. Per-channel peak meters (and a master meter pair) read the post-volume signal and decay over ~300ms for visible peak-hold, so you can spot a hot channel by eye instead of by ear-pain.

There is no EQ and no aux send - this is a clean summing mixer, not a console. We chose that on purpose: in a modular, EQ and FX are their own modules (Filter, Reverb, Delay, Distortion), and the mixer's job is to balance and place. Keep effects on dedicated channels and route them in pre-mixer, the way a Eurorack performance setup does.

In a patch

The mixer almost always sits between the voices and the Output. Every VCA (or drum voice, or effect return) terminates in one of the mixer's mono inputs; the mixer's L and R outputs go to the corresponding inputs on the Output. A typical four-voice patch occupies channels 1-4, leaving channels 5-8 free for an FX return from a Reverb or Delay, plus a Stream In or sidechain source.

Pan voices intentionally. A common trick: pan the bass dead center, the kick center, and spread the melodic voices in a stereo arc - say -0.5, 0, +0.5 - so each lead has its own slot in the field. Drums and bass sit center because the low frequencies need both speakers to carry them; ear-level sources can be moved without losing definition.

Use the mute switches as performance gestures: drop everything except the kick to land a downbeat, then slam channels back in. Combined with a Clock and a Step Sequencer driving rhythm, the mute buttons are the closest a modular gets to a song arrangement.

Outputs

Out L (audio) — Left stereo output. The mixed-down left channel of all 8 inputs after volume, pan, and master processing.
Out R (audio) — Right stereo output. The mixed-down right channel of all 8 inputs.

Controls

Master — Master volume (0 to 1). Controls the overall output level of the entire mix. Start around 0.8.
M.Pan — Master pan (-1 to +1). Shifts the entire stereo mix left or right. Center (0) leaves the stereo image unchanged.

Inspired by

A classic Eurorack performance-mixer layout: a bank of mono inputs, each with its own fader, pan, and mute, all summed to a stereo master with its own level and balance. Constant-power pan (cos/sin law) keeps perceived loudness even as you sweep across the field.

WMD Performance Mixer
Intellijel Mixup
Frap Tools 321

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