Support topics
Choose the mode in Correction mode at the top of the Tuning sidebar. Each item in the list carries the app’s own one-line description, repeated here word for word.
| Mode | What the app says | What plays | Added delay |
|---|---|---|---|
| Zero latency | “Corrects tonal balance with standard EQ filters. Adds no delay.” | The IIR EQ bands. | None |
| Minimum phase | “The same correction as Zero latency, built as one long filter instead, so it sounds almost the same. Adds no delay.” | A minimum-phase FIR in place of the EQ bands, at the same magnitude. | None |
| Mixed phase | “Minimum phase in the bass, linear phase above it. Adds the same delay as linear phase.” | One FIR in place of the EQ bands: minimum phase below the transition, linear phase above it. | 4095 samples |
| Excess phase only | “Corrects tonal balance like Zero latency, plus the measured timing errors that tonal correction cannot fix, only where the measurement is reliable. Adds the same delay as linear phase.” | The IIR EQ bands, plus an all-pass FIR for the measured excess phase. | 4095 samples |
| Linear phase | “Corrects tonal balance without shifting timing at any frequency. Adds delay, so suits playback more than live use.” | A linear-phase FIR in place of the EQ bands, at the same magnitude. | 4095 samples |
Minimum phase sounds almost the same as Zero latency, and that’s expected. Peaking EQ filters are minimum phase, so a minimum-phase FIR with the same magnitude has close to the same phase.
What it’s doing. In the app, for Minimum, Mixed and Linear phase, AudioMap renders the EQ band stage (your EQ bands, their band limits and the Wet/Dry mix) through the real correction engine, takes the impulse response, and designs an 8192-tap FIR to match its magnitude. The FIR replaces only that stage: the high-pass and low-pass filters, tilt and target stay standard filters in every mode. AudioMap Engine and the plugin build the same band-stage FIR for each mode.
Latency
The line under the Correction mode menu shows what the current mode adds at your interface’s sample rate: No added latency for Zero latency and Minimum phase, or Adds … ms latency for the other three.
- Zero latency, Minimum phase: no added delay.
- Mixed phase, Excess phase only, Linear phase: 4095 samples. That’s 85.3 ms at 48 kHz. The figure is fixed in samples, so it is shorter in milliseconds at higher sample rates.
This is the correction filter’s delay only. Alignment delays and your interface’s own latency are separate. The plugin reports this filter delay to your DAW, never the alignment delay, so delay compensation doesn’t undo the alignment.
Delayed modes and live sound
With Mixed phase selected, a Linear phase above control appears under the menu. Below that frequency the correction is minimum phase; above it, linear phase.
What it’s doing. A linear-phase filter moves an EQ band’s ringing ahead of the sound, as pre-ringing. A narrow band rings longest at low frequencies. The default is set so the narrowest band the fit can place (Q 15) pre-rings for less than about 20 ms, which pre-masking hides: 15 / (π × 0.020 s), about 239 Hz. Double-click the control to return to the default.
The mode belongs to the sound system, not to a source. Every source plays the same mode. The mode picker on an expanded source row is read-only. In help mode (press H), hovering it explains that one correction mode applies to the whole sound system, and points you to the Correction row at the top of the sidebar.
Every source also plays the same filter delay. In Mixed phase, Excess phase only and Linear phase, a source with no tuning, with its own internal crossover network or with no EQ bands plays the same 4095-sample delay as the others.
- A new project starts in Zero latency. Tune & Listen at the end of an auto-capture run sets Minimum phase when it builds the first tunings.
- A project saved with different modes on different sources opens with the most common one. If there’s a tie, it opens in Minimum phase.
- A source with its own internal crossover network keeps its EQ as standard filters in every mode.
- The plugin offers As saved (“Uses the mode the correction file was saved with.”) or any of the five modes. See Tuning for how Wet/Dry behaves in each mode.
A speaker’s measured phase is two parts: the minimum phase that goes with its magnitude response, and the excess phase on top of it. EQ fixes the first as a side effect. Excess phase only also corrects the second, with an all-pass filter that changes timing and not level.
What it’s doing.
- It finds the span to correct: between the two passband edges AudioMap measured for that source. Both edges must be measured, on a capture that carried coherence.
- It splits the measured phase into minimum and excess parts and removes the best-fit straight line from the excess. The slope of that line is plain delay, which is the alignment’s job. Its constant offset is removed too, and left uncorrected.
- It plays the inverse of what’s left, at unit magnitude, fading to nothing at each edge of the span. The EQ bands still do the tonal correction.
When it can’t design the all-pass for a source, that source plays its EQ only, and the source row (expanded) says why:
- EQ only — no phase measurement
- EQ only — no coherent measured range (AudioMap doesn’t have both passband edges, measured on a capture that carried coherence)
- EQ only — measured range …–… Hz is too narrow (too narrow for the filter to shape)
- EQ only — measurement is silent across its range
In help mode (press H), hovering the line shows: “Excess-phase correction needs a coherent phase measurement across this speaker’s range, so this speaker plays its EQ correction only.”
A refused source still plays the same 4095-sample delay as a source the all-pass corrects.
Tune from a measurement, not an RMS average
Also in Align & tune
Checked against AudioMap 2.0.0. Something wrong or missing? Tell us.