Vocal Booth Design Calculator

A vocal booth's job is to kill reflections fast enough that a microphone hears a dry, close-up voice with no boxy room sound behind it, and this calculator works from your booth's dimensions and how much of its interior surface gets acoustic treatment to predict that outcome. It computes total room surface area, applies your treatment percentage to find the treated area, and assigns a Noise Reduction Coefficient (NRC) by foam or fiberglass thickness — thin 1-inch panels absorb only around 0.3 of incident sound energy, while 4 inches or more approaches full absorption near 1.0, since thicker porous absorbers reach effectively down to lower frequencies. Combining treated-area absorption with an assumed 0.05 NRC for the untreated bare surfaces (drywall, glass, etc.) gives total absorption in sabins, which feeds the classic Sabine reverberation formula to estimate RT60.

The ideal vocal booth range is roughly 0.2-0.4 seconds — long enough to avoid an unnaturally dead, claustrophobic sound but short enough to stay controlled; the calculator rates your result as ideal, acceptable, or too reverberant against that band. It also flags the lowest problematic standing-wave frequency, derived from the speed of sound and twice the booth's longest interior dimension — small booths with parallel, untreated walls are prone to audible resonant buildup at this frequency and below, which acoustic foam alone does little to fix since bass wavelengths are too long for typical treatment thickness; bass traps in the corners are the real remedy. Material cost simply scales treated area by a per-square-foot rate that rises with panel thickness.