V-MidsiderOut

What it is

V-MidsiderOut is the zero-latency decoder for a Mid/Side signal. It expects Mid on the left input channel and Side on the right input channel, then writes L = Mid + Side to the left output and R = Mid - Side to the right output. Its only parameter is Bypass.

Controls & parameters

The editor also shows a static decode matrix and processing-status display. These are not additional parameters.

Workflow / how to use it

1. Place V-MidsiderOut after V-MidsiderIn and any processing that treats the two channels as Mid and Side.
2. Confirm that Mid is on the left channel and Side is on the right channel entering V-MidsiderOut.
3. Leave Bypass off to decode the signal to normal left/right stereo.
4. Use the host’s normal stereo output after the decoder.
5. If bypassing for a comparison, remember that Bypass leaves the incoming M/S channel order unchanged rather than decoding it.

Use cases

• Complete an M/S chain: Pair V-MidsiderOut with V-MidsiderIn around stereo EQ, compression, or other processing that operates on the two channels independently.
• Decode an M/S render: Convert a file or routed pair with Mid on the left and Side on the right back to conventional L/R for monitoring or delivery.
• Restore width processing: Change the Side level or apply another operation between the encoder and decoder, then use V-MidsiderOut to reconstruct the stereo image.
• Unity round trip: With no processing between the pair, the half-scaled encoder values are added and subtracted back to the original channels: 0.5 * (L + R) + 0.5 * (L - R) = L, and the corresponding difference gives R.

Specs & requirements

• Formats: AU and VST3.
• Audio I/O: Stereo input and stereo output are configured. The source layout validator also accepts matching mono input/output layouts, but decoding runs only when at least two input and two output channels are present; a mono layout is therefore left unchanged.
• Latency: Zero processing latency. The processor reports a zero-second tail.
• Sample rates: No fixed sample-rate list is declared by the plugin source.
• Precision: Supports both FP32 and FP64 processing and follows the host’s active precision.
• MIDI: No MIDI processing is enabled.
• State: Bypass is stored as APVTS XML state. The plugin exposes one host program and does not implement preset programs.
• Platform: Workspace audio-toolbox build guidance targets macOS 10.15 or later.

Notes / caveats

• The decoder assumes the incoming channels are M/S, not ordinary L/R. Feeding a conventional stereo signal to V-MidsiderOut intentionally produces sum/difference output rather than a transparent pass-through.
• Bypassing V-MidsiderOut passes M/S unchanged; it does not convert it to L/R.
• V-MidsiderOut has no width, gain, or metering control. Make those changes in the processing stage between V-MidsiderIn and V-MidsiderOut.
• The conversion is an in-place, per-sample matrix with no parameter smoothing, metering, allocation, or delay in the processing loop.