Channel Strip Stereo Widening Plan

Goal

Add useful width control to each mixer channel without weakening mono compatibility, changing instrument patches, or confusing width with pan.

Recommended Control Set

• Width: 0% collapses to mono, 100% preserves the source, and 200% increases side level.
• Bass Mono: adjustable crossover, initially 120 Hz, below which the signal remains centered.
• Mono Check: momentary/latching audition of the channel collapsed to mono.
• Correlation warning: a small, non-distracting warning only when the widened signal develops persistent negative correlation.

DSP Placement

1. Instrument or sample output.
2. Channel insert processing and EQ.
3. Mid/side width matrix with bass-mono protection.
4. Channel pan and gain.
5. Post-pan meters and effect sends.

The width stage should use a gain-compensated mid/side matrix. The first beta implementation should not use Haas delay, because time offsets can sound dramatic in stereo while disappearing or comb-filtering in mono.

State And Automation

• Parameters belong to the mixer channel, never to an instrument preset.
• Width, Bass Mono, and Mono Check state persist with the project.
• Width and Bass Mono are automation and MIDI-learn targets.
• Metering occurs after width and pan so the display reports the audible stereo result.

UI Placement

Place the controls on a dedicated WIDTH channel-strip subpage beside the existing processing pages. Use one large horizontal Width control, one smaller Bass Mono control, a Mono Check button, and a compact correlation indicator. This keeps the main strip clean and leaves enough travel for precise adjustment.

Verification

• 100% nulls against the bypassed source.
• 0% produces identical left and right channels.
• Hard pan still produces silence on the opposite output meter.
• Bass below the selected crossover remains mono at all width settings.
• Automation is click-free and updates meters in real time.
• Project save/load restores all settings exactly.