ACOUSTIC PLANNING TOOL
Know your room.
Understand your bass.
Explore room resonances and speaker placement in rectangular, L-shaped, and U-shaped rooms. Move the speakers and listening position to compare predicted low-frequency behavior.
Calculation methodAnalytical rectangular-room modesModels rigid boundaries and a uniform ceiling height. Predictions are for planning—not a substitute for measurements.
INTERACTIVE FLOOR PLAN
Speaker & listening positions
Speaker Listener
Drag the speaker and listener markers to explore different placements. Select a room mode to see its pressure pattern.
Position coordinates appear here
Coordinates measured from the lower-left corner of the overall room bounding box.
LOW-FREQUENCY BEHAVIOR
Estimated response at the listener
Room + speaker Speaker only
Relative response with coherent direct-field propagation and damped modal corrections. Mode lines are optional; horizontal grid lines are spaced at 5 dB. This is not measured or calibrated SPL; use it to compare layouts, not predict exact peak amplitude.
RESONANCES
Room modes
| Frequency | Mode | Coupling* |
|---|
*Coupling combines pressure at the source(s) and listener. It is not an absolute mode strength or audibility score. Click a row for its pressure map.
ACOUSTIC DECAY
Estimated reverberation time
Interpretation
Calculate to see modal behavior.
Rectangular modes use the analytical rigid-room equation. L/U modes use the lowest 28 horizontal modes from a 2D finite-difference eigenvalue calculation on the stepped floor plan, combined with analytic vertical modes for constant ceiling height; the L/U results are therefore incomplete near the upper frequency limit. All boundaries are assumed rigid. The solver is grid-limited; frequencies near the high-frequency limit and narrow corners are less reliable. No furniture scattering, windows, openings, impedance walls, phase-correct loudspeaker model, or direct sound/reflection paths are simulated. Speaker-to-listener response is a relative, uncalibrated direct-field plus damped modal Green-function correction referenced against heavily damped modes. The reference model, rigid wall assumption, and uniform RT60 can significantly affect peak/dip magnitudes. Optional room gain is a simple 6 dB low-frequency shelf whose knee follows the room longest dimension, not a measured boundary model; complex room reflections and path-dependent phase remain unmodeled. Coordinate inputs and placement can be compared but do not predict exact in-room peaks. Verify recommendations with a measurement microphone.