Crossovers

Crossover is near the top of the Tuning sidebar. Open it with its chevron. After an auto-capture run it opens by itself, except when every suggestion is already on or the only one left is a frequency you switched off. Next to the title, a count shows how many crossovers are on, for example 2 of 3 on.

You need at least two speaker groups. With one, it says Add a second group to suggest a crossover.

Crossover design needs AudioMap Pro or a trial. On other tiers, opening the section or turning it on shows the upgrade prompt instead.

• Each sub (band-limited) group gets one low-pass (LP). If the sound system has no full-range top, adjacent groups are paired in order instead.
• Each full-range top group gets a high-pass (HP) when it overlaps the sub or meets it across a measured gap.
• Tops never cross over to each other. Two full-range groups are aligned broadband instead.
• The suggested top that reaches lowest is the sub’s default partner, and its HP is linked to the sub’s LP: one frequency and one filter for both sides. Another suggested top whose own frequency is above the LP keeps its own HP.
• A sound system with no full-range group pairs neighbouring groups instead.

What it’s doing. AudioMap looks at the overlap between the two groups’ measured passbands, from the top’s low −6 dB point to the sub’s high −6 dB point (where a side doesn’t roll off, the end of its measured passband), and never below the sub’s own low end. It scores each frequency in that window by how coherent both measurements are there, and marks it down where their levels are more than 10 dB apart. The best-scoring frequency is the suggestion. Where several frequencies score within 1% of the best, it takes the one nearest the middle of the window (on a log scale). If the two never meet but both edges were measured, it suggests the middle of the gap (on a log scale).

The response it reads is chosen automatically. For subs: the coverage average, then the listening position, then the near-field sweep. For other groups: a gated capture from the best-geometry position when one passes the room gate, then the listening position, then the coverage average, with the near-field sweep last. A capture taken with a crossover engaged is skipped. To use a different one, right-click the group row, choose Choose measurement… and pick Listening position, Coverage area average, On-axis near-field (wizard sweep) or a single measurement under All measurements. Automatic (follows your captures) goes back to the default.

When there’s no suggestion, the row says why, for example:

• No suggestion. Measure Subs first.
• No suggestion. Subs’ high end wasn’t measured.
• No suggestion. The overlap between Subs and Mains couldn’t be judged.

Set by hand opens the field to type your own frequency. Where a speaker’s measured limit is known, the field starts there. In help mode (press H), hovering the field says it’s the measured limit, not a suggested crossover.

1. A new row’s field already shows the suggestion. Type a frequency or step it to change it. Where the row holds a different value, Use suggested <N> Hz appears under it. In help mode (press H), hovering it says “Replace this frequency with the one from the latest capture.”
2. Check the filter: Linkwitz-Riley, Butterworth or Bessel, at 12, 18, 24, 36 or 48 dB/oct. The default is Linkwitz-Riley 24 dB/oct (LR4). Linkwitz-Riley has no 18 dB/oct.
3. Turn it on with the section’s power button or the filter’s own button (below).

While any crossover is on (the section power button is lit), typing, stepping or Use suggested turns that row on. Otherwise the value is only stored. A new capture updates the suggestion, not your frequency: only Use suggested or a partner pick (below) replaces it.

• Section power button (in help mode: “Turn every crossover off. Each frequency is kept.”). When off, it turns on every crossover that has a frequency. It never replaces a frequency you already have.
• Each LP and HP has its own button. In help mode it says, for example, “The Subs low-pass is on. Click to turn it off; its frequency is kept.”
• Linked / Unlinked: linked, the LP and HP share one frequency and one filter. Unlink to set each side on its own.

When a sub could cross to more than one top, the top’s name on the sub’s row (dotted underline, with a caret) is a menu. It lists each of those tops with its suggested frequency. Picking one sets the row to that partner’s suggested frequency at once. The filters move straight away if a crossover is already on; otherwise only frequencies already stored move.

The same choice sets the sub’s relation on the Timing tab, so the sub is aligned to the top it crosses to. The sub’s level is matched automatically to the level of that partner just above the crossover (a lift of −6 to +12 dB). What plays is limited to +6 dB in total, and a limited speaker is marked; Tuning › Levels shows each part.

A top on its own row has a menu too: From its own low end, or With Subs to cross over with the sub. A top set to cross with the sub follows it. In help mode, hovering its frequency says “Follows the Subs crossover. Change it on the Subs row.”

• Mains measured down to 90.0 Hz, leaving a gap from 70.0 to 90.0 Hz. The sub’s low-pass is on and stops below where the top was measured down to, so nothing plays across that range.
• Mains and Subs both play from 60.0 to 110 Hz. Both filters are on and the sub’s low-pass sits above the top’s high-pass and the top’s measured low end, so both play across that range.
• LR 12 needs one side inverted. Time alignment sets it. (for example) Shown on a crossover that is on, when both sides use the same 12 or 36 dB/oct slope, in any family, and play the same polarity. If you set either polarity by hand, the second sentence reads Subs polarity is set by hand: invert it in Timing.