Theater Calculators
Stereo Speaker Equilateral Triangle Setup
https://www.theatersizing.com/calculators/stereo-triangle/
Estimate only — not a calibrated SPL meter, an acoustic report or an electrical design. Confirm with measurement.
Stereo Speaker Equilateral Triangle Setup
An equilateral triangle puts each speaker as far from you as they are from each other. Toe-in starts near 30° from straight ahead; listen and tweak.
Inputs
Results
- Speaker separation
- 2.80m
- Starting toe-in
- 30°
Calculation method
Separation equals listening distance. Starting toe-in is 30° from the forward axis so the axes cross just behind the skull.
Exact formula
s = d. Toe-in start 30°. Limits: ignores room boundaries, speaker directivity and the fact that cinema L/R often track the screen edges instead.
Frequently asked questions
Always equilateral?
It is the textbook start. Some rooms go slightly wider. Do not go so wide that the centre collapses.
Toe-in to the nose?
Start so axes cross just behind the head. Too much toe-in shrinks the stage.
What about a centre channel?
Film L/R often follow the screen, not a music triangle. Recalculate after the screen is hung.
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