Metronome and tuner
Keep steady time with an accurate click, and tune your oud, guitar, violin or ukulele with your microphone.
Metronome
Time signature
Clicks are scheduled ahead on the audio clock, so they stay steady even when the screen is busy. Keep the page open: some phones pause sound when the screen locks.
Tuner
Instrument
The microphone is used only while the tuner is on, only on your device. Nothing is recorded, uploaded or saved. Stopping the tuner (or leaving the page) switches the microphone off.
Good to know
Ordinary page timers can drift by tens of milliseconds. Here each click is booked a moment ahead on the sound card's own clock, a method from the Web Audio community, so the beat stays steady.
It compares the sound with itself shifted by tiny delays to find how often the wave repeats (the YIN method). 100 cents make one semitone; within about 5 cents sounds in tune to most ears.
A common Arabic tuning, from the lowest course to the highest, is C2 F2 A2 D3 G3 C4 (do fa la re sol do). Players also use other tunings: some tune the lowest string to D, E or F, and Turkish ouds sit a tone higher. Pick what your teacher uses.
Standard pitch sets the A above middle C at 440 Hz. Some orchestras tune a little higher, to 442 or 443. Move the A4 slider if your group does.
Sources: ISO 16:1975, standard tuning frequency A4 = 440 Hz. De Cheveigné A. and Kawahara H. (2002), "YIN, a fundamental frequency estimator for speech and music", Journal of the Acoustical Society of America 111(4):1917–1930. Chris Wilson, "A tale of two clocks: scheduling Web Audio with precision" (web.dev, 2013), for the look-ahead scheduling. Oud tuning: the low C (C–C) Arabic tuning, C2 F2 A2 D3 G3 C4, as described by oud teaching guides (oudforguitarists.com, "Best oud tuning for beginners", which names it one of the two most common Arabic tunings, with high F tuning); other tunings exist. Guitar E2 A2 D3 G3 B3 E4, violin G3 D4 A4 E5 and ukulele G4 C4 E4 A4 are the standard tunings.