PHIXER for Stereo Imager: width tools and mono phase cancel
A stereo imager, Mid-Side width boost, or Haas delay can feel huge in headphones. On phone, Bluetooth, club PA mono, or livestream fold, bass and body disappear while edges stay. Width is not the same job as stereo phase repair. Polarity, timing, Mid/Side balance, and true mono listen come first. Free phase-repair helps after residual L/R fights remain on a stereo bed you must keep stereo. It is not a stereo imager, and it does not replace a mono audition after you widen.
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 stereo imager, not a Mid-Side encoder, not a Haas delay, and not a substitute for mono audition after you widen. Use it after hygiene, when residual spectral cancellation remains on a stereo bus you must keep stereo.
Three stereo-imager failure modes this page covers
- Width boost that cancels on fold. Headphones feel wide; phone / club / livestream mono hollows bass and chest. Polarity and timing first; spectral tools last.
- Imager next to Mid-Side decode. Side boost into an imager (or the reverse) shares the same mono scoop when Mid and Side fight. Cousin: PHIXER for Mid-Side.
- Imager on multiband or bus stacks. Split-band width or bus imaging hollows a band when paths recombine. Cousin: PHIXER for Multiband.
Fast stereo-imager mono audition (about 60 seconds)
- Solo the imaged path (or the bus that carries it). Sum L+R with a monitor controller or utility. Do not mute one side to "hear the problem."
- A/B stereo vs mono across a sustained soft source and a kick hit. Note what disappears: kick body, bass weight, pad mid, vocal chest, hat air.
- Bypass the imager / width tool briefly. If mono weight returns, the Side boost / Haas delay / correlation settings may be the scoop, not free stereo. Then check Ø and a few samples of attack timing on L vs R.
- Confirm on a phone speaker, then again after Mid-Side or multiband joins the bus. Re-check after the master.
Honest order of fixes (before spectral phase rotation)
1. True mono listen after you widen
Hard L+R sum with both ears open on the imaged output or bus sum. Habit: mono check workflow.
2. Side amount, Haas delay, and correlation
If mono scoops only when Side is high or Haas is long, fix the width first. Linked stereo imagers often behave better than dual-mono wideners that fight each other.
3. Polarity before more processing
Flip Ø on one bus path or one side 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 after width. Often enough on phones and club fold.
5. Mid-Side and multiband before spectral tools
Mute Side boost or mute multiband width briefly. If mono weight returns, fix those cousins first. Cousins: Mid-Side and Multiband.
6. Skip when intentional thin mono is the point
Some Side-heavy beds are meant to stay edge-only in mono. Honesty list: When not to use PHIXER. Also see PHIXER vs stereo imagers.
7. Only then audition residual L/R spectral fights
If the stereo bed must stay stereo and fold still hollows 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.
Stereo imager setups and common mono failures
| Setup | Common mono failure | First fix |
|---|---|---|
| Mid-Side width boost | Bass scoops on phone fold | Mono listen; less Side; check Ø |
| Haas / short delay widen | Body dips when summed | Shorter delay; polarity; timing |
| Vector / correlation imager | Center thins when correlation drops | True mono; restore Mid; Ø |
| Imager after M/S decode | Side + width cancels on fold | Mid-Side |
| Imager on multiband bus | One band hollows when recombined | Multiband use-case |
| Imager into master | Streaming / phone fold thins | Mono check master; less Side |
Mid-Side and multiband cousins (short version)
- M/S decode and Side boost share center cancel with width tools when Mid and Side fight. Full write-up: PHIXER for Mid-Side.
- Multiband splits that carry per-band width share center cancel when bands recombine. Full write-up: PHIXER for Multiband.
- Polarity and attack timing still come first on every cousin. Spectral tools after residual L/R fights only.
When not to reach for PHIXER
- Side amount / Haas delay / correlation choices are simply wrong (fix the imager first).
- Wrong polarity on one bus path or one folded channel (flip Ø first).
- Obvious attack misalignment between L and R (nudge first).
- You only need a mono-safe center print, not a stereo bus.
- Intentional Side-heavy texture that is meant to stay thin in mono.
- Honesty list: When not to use PHIXER.