Question 1

Is SonicForge free?

Accepted Answer

Yes. It is free, MIT-licensed, open source, and needs no account or sign-up. There is no paywall and no advertising.

Question 2

Does it upload anything or record me?

Accepted Answer

No. There is no backend. No analytics, no telemetry, no CDN and no cookies. The microphone opens only while a room-calibration measurement is running and is released as soon as it ends; no audio is recorded or stored, and only a 96-point magnitude curve leaves the analyser, staying in your browser.

Question 3

What frequency range can it generate?

Accepted Answer

From 0.05 Hz to just below Nyquist - 24 kHz at the default 48 kHz sample rate, or 48 kHz if you switch the audio context to 96 kHz. That covers infrasonic, audible and ultrasonic bands.

Question 4

Why can I not hear frequencies below 20 Hz?

Accepted Answer

Your speaker cannot reproduce them. A laptop driver rolls off below about 400 Hz and a bookshelf speaker below about 50 Hz, so the signal is being generated correctly but not radiated. Use the am() command to deliver an infrasonic envelope on an audible carrier instead.

Question 5

How does the speaker water eject work?

Accepted Answer

It plays a 165 Hz pulse train at high excursion, which moves the driver far enough to physically push trapped water out of the grille. Point the speaker downward and take headphones off first - at that level in-ear playback is genuinely unsafe.

Question 6

Does it work offline?

Accepted Answer

Yes. A service worker precaches every shipped file, so once the page has loaded it runs with no connection at all. It can also be installed as a progressive web app.