audioJS

Room and speaker measurement

A sine sweep plays through your speakers and is recorded by your microphone. You get the frequency response, RT60 and latency.

Turn the volume to a comfortable level, place the microphone where you listen, then press start. The sweep lasts 3 seconds.

Nothing is uploaded. Everything runs in this tab with @audio/measure, @audio/synth, @audio/mic.

Room acoustics measurement, no software to install

The page plays a logarithmic sine sweep from 20 Hz to 20 kHz through your speakers, records it with your microphone and computes the impulse response by deconvolution with @audio/measure. From the impulse response it derives the frequency response (1/6-octave smoothed, normalized at 1 kHz), the reverberation time RT60 and the round-trip latency. Everything runs in the browser.

How to get a useful measurement

Reading the result

A response within ±3 dB from 100 Hz to 10 kHz is good for an untreated room. RT60 below 0.4 s is what mixing rooms aim for; living rooms sit around 0.5 s. Latency includes your audio interface and operating system, so it is not a pure acoustic figure, but it is stable for the same setup.

Questions

What do I need? Speakers or headphones and a microphone in the same room. A laptop measures itself; for real speaker data use an external microphone, ideally an omni measurement mic, at the listening position.

What is RT60? The time the sound field takes to decay by 60 dB after the source stops. It is estimated from the impulse response by Schroeder backward integration and extrapolated from the -5 to -25 dB slope (T20).

Why does the response look wild below 200 Hz? Room modes: standing waves between walls create peaks and dips of 10 dB or more. That is the room, not the speaker. Move the microphone and compare.

Is anything uploaded? No. The sweep, the recording and the analysis stay in your browser.