Reference tone

1000 Hz — 1 kHz Reference Tone

1 kHz is the audio industry's universal reference tone — used for level calibration, line-up tones and equipment testing.

Audio visualization
Hz

 

20 Hz20 kHz
Waveform
Volume50%
L/R BalanceCenter

Press Space to play

About the 1000 Hz tone

A 1000 Hz sine wave is the go-to signal for setting and checking audio levels. Broadcast and studio “line-up” tones are almost always 1 kHz, because meters and the ear are both well-behaved at that frequency.

It's also handy for a quick channel check: play the tone and use the balance control to confirm your left and right speakers or headphones are both working and roughly matched.

Because 1 kHz sits in the most sensitive part of human hearing, it makes a reliable tone for confirming that a signal chain is passing audio at all.

Technical details

Frequency
1000 Hz
Nearest note
B5 (+21¢)
Category
Reference tone
Period
1.00 ms
Wavelength (air)
34.3 cm
Octave up / down
2000 Hz / 500 Hz

Common uses

  • Set or check audio levels (line-up / reference tone)
  • Test speakers, headphones and audio interfaces
  • Confirm left/right channels with the balance control

Frequently asked questions

What is a 1000 Hz (1 kHz) tone used for?

1 kHz is the audio industry’s universal reference: it’s used to set and check levels, as a broadcast and studio “line-up” tone, and to test whether a signal chain, speaker or interface is passing audio cleanly.

How do I test my speakers or headphones with 1000 Hz?

Play the tone at a moderate level and use your balance control to confirm the left and right sides are both working and roughly matched. Because 1 kHz sits in the ear’s most sensitive range, any dropout or imbalance is easy to notice.

What note is 1000 Hz?

1000 Hz falls between B5 and C6 on a keyboard, but it’s used as a technical reference rather than a musical note. The generator shows the nearest note and how many cents away it is.

Nearby frequencies