Tap "Enable" up top once when the page loads, then Start Session each drive.
Audio: —
Drivetone generates its engine tone directly — no sound files needed. It reacts to speed; Bass/Mid/Treble below control each layer's volume live as you drive. Exterior boost and Play continuously live under Settings → Playback.
Sub/Bass/Mid/Treble each drive an oscillator layer — slide up for more of it, down to quiet it, and pick a waveform per layer to change its character. Growl darkens or brightens the overall tone; Thickness adds a detuned chorus layer to Treble for a fuller sound. Needs Web Audio (see the Audio status line above).