PHIXER for Stereo Mic Pair: XY, ORTF, and A-B / spaced pair phase
A stereo mic pair can feel wide and honest in headphones: coincident XY, near-coincident ORTF, or a wider A-B / spaced pair on piano, choir, ensemble, or a room. On phone playback, Bluetooth, club PA mono, livestream fold, or a classical hall feed that goes LoRo, the middle thins and low-mid body dips while edges stay. Polarity and a few samples of timing come first. Free phase-repair helps after residual L/R fights remain on a stereo pair you must keep stereo. It is not a time-align tool, not a widener, and it does not replace a true mono listen on the pair.
Download PHIXER free YouTube tutorial
PHIXER is free stereo phase-repair (VST3/CLAP/AU · Win/Mac/Linux) from Riverflux Audio. Frequency-aware phase rotation for leftover L/R fights on stereo material. It is not a polarity button, not a delay matcher, not a widener, and not a substitute for mic placement. Use it after hygiene, when residual spectral cancellation remains on a stereo bed you must keep stereo.
Three stereo pair failure modes this page covers
- XY / coincident pair. Capsule angle and polarity still fight Mid on some sources. Image feels wide in cans; piano or choir body dips on phone fold.
- ORTF / near-coincident pair. 17 cm / 110° spacing plus angle can hollow the center when summed. Common on ensemble and room capture.
- A-B / spaced pair. Wider spacing adds time-of-arrival fights that polarity cannot fix. Cousin: PHIXER for Piano (lid XY + spots + spaced pair).
Fast stereo pair mono audition (about 60 seconds)
- Sum L+R on the pair bus (or monitor controller mono) with both capsules open. Do not mute one side to "hear the problem."
- A/B stereo vs mono across a sustained note and a transient. Note what disappears: low-mid body, attack, hall tone, or center image that was actually cancellation.
- Flip Ø on one capsule. Keep the flip that returns body without killing the pair. Then nudge a few samples of L vs R attack timing before chasing plugins.
- Confirm on a phone speaker, then again after bus EQ / compressor / reverb send. Re-check after OH / room beds join the pair. Cousin: PHIXER for OH / Room.
Honest order of fixes (before spectral phase rotation)
1. True mono listen on the full pair
Hard L+R sum or monitor mono with both capsules open. Habit: mono check workflow.
2. Placement and angle before plugins
XY angle, ORTF spacing, and A-B width are the first stereo-image tools. If the pair is too wide for the room, mono will always scoop the middle.
3. Polarity before more processing
Flip Ø on one capsule while mono. Keep the flip that returns body. Guide: polarity vs phase.
4. Attack timing before spectral tools
Nudge a few samples or ms so transient peaks agree across L and R. Often enough on phones, halls, and livestream fold.
5. Skip when intentional width or thin mono is the point
Some A-B pairs are meant to stay wide and thin in fold. Honesty list: When not to use PHIXER.
6. Only then audition residual L/R spectral fights
If a stereo pair must stay stereo and fold still hollows a band after the steps above, gentle frequency-aware phase rotation can help. Prove it with mono A/B. Watch the YouTube tutorial and the mono demo.
Pair types and common mono failures
| Setup | Common mono failure | First fix |
|---|---|---|
| XY coincident | Center body dips; edges stay | Polarity + angle; mono listen |
| ORTF near-coincident | Choir / ensemble middle hollows | Spacing check; flip Ø; nudge timing |
| A-B / spaced pair | Low-mid scoop from time-of-arrival | Narrow the pair or time-align first |
| Piano lid XY + spots | Lid pair fights spots on fold | Piano use-case |
| OH / room under a pair | Bleed + pair both hollow | OH / room use-case |
| FOH stereo pair + stream | Hall pair cancels on matrix / stream | Live FOH use-case |
OH / room, live FOH, and piano cousins (short version)
- Overheads and rooms can pile more cancellation under a stereo pair. Full write-up: PHIXER for OH / Room.
- Live FOH stereo pair plus foldback / stream matrix is the venue cousin of the same fold. Full write-up: PHIXER for Live FOH.
- Piano lid XY + spots + spaced pair is the keyboard cousin. Full write-up: PHIXER for Piano.
- Launch assets and what's new: What's new.
- Polarity and attack timing still come first on every cousin. Spectral tools after residual L/R fights only.
When not to reach for PHIXER
- Wrong polarity on one capsule (flip Ø first).
- Obvious attack misalignment on an A-B pair (nudge or narrow first).
- You only need one hero capsule or a mono-safe print of the pair.
- Intentional wide A-B texture that is meant to stay thin in mono.
- Honesty list: When not to use PHIXER.