Room Acoustic Simulator — design target, speaker coverage heatmap and verdict

What the Room Acoustic Simulator does

Enter a room size and choose an application; the application suggests a design target SPL — the level you want in the listening area — and you can set your own. Add loudspeakers from 2265 models across 45 brands, mix brands and models freely, drag each one into place, aim and tilt it, and read how evenly the level falls across the room. Every speaker keeps a stable number (S1, S2 …): change its model in place, duplicate it, mirror it into a symmetrical pair, or remove it, and undo any step.

Of those 2265 models, 2134 are checked against a source naming that exact model, 13 against a secondary specification source, 44 are carried as indicative, and 74 are under review. The picker prints that status beside every model. A further 236 speakers in the public catalogue cannot be placed here because this calculation cannot represent them honestly — subwoofers, line-array elements, steerable columns, and models whose coverage angle is unsourced or disputed. The picker still finds them and says why.

How the estimate is calculated

It is a free-field, direct-sound estimate. Each loudspeaker loses level with the inverse-square law — 6 dB per doubling of distance from a 1 m reference, the point-source case — and is attenuated off its axis by a simplified roll-off: 6 dB at the edge of its published −6 dB coverage angle, growing beyond it. Wall and bracket cabinets are aimed and tilted; ceiling and pendant speakers fire straight down, so their coverage cone is measured from vertical. Overlapping speakers are summed as energy (two equal speakers add 3 dB). Reflections, reverberation time, room modes, air absorption, per-frequency behaviour and phase are not modelled.

A line or column source radiates a cylindrical wavefront near the cabinet and loses closer to 3 dB per doubling of distance there. This tool applies point-source spreading to every model, so for a line or column source it overstates how much quieter the back of the room is than the front — the front-to-back variation shown is larger than the cabinet would produce.

The level is not taken from the speaker’s maximum. All speakers share one system level at 1 m (plus any trim you set), and the tool solves that level so the median of the room equals your design target. A speaker’s published maximum SPL is only a ceiling: the tool never drives a speaker above it, reports when the target cannot be reached even at the ceiling, and flags a speaker left with less margin than the application’s programme peaks typically need.

Reading the results

Within ±3 dB is the share of the listening area within 3 dB of the design target — a planning convention, not a standard: two speakers whose −6 dB coverage edges meet leave roughly a 6 dB window. Evenness is the level range across the middle 80% of the room (10th to 90th percentile), so a single hot corner does not dominate it. A coverage gap or hot spot is named only when at least 10% of the room is more than 6 dB below or above the target. Headroom is how far below its published maximum a speaker runs; where a model has no usable published maximum it is shown as not assessed rather than estimated.

Suggested design targets

Each application suggests a starting target. These are planning assumptions informed by common practice, not standards, and you can change the target for any application.