Sound Check Tone Generator

Soundcheck Tongenerator, App Store Icon

This app is available at Apple’s App Store for iPhone and iPod touch at no charge. Current version is 1.21.


Sound Check Tone Generator provides sine tones of the exact frequencies to which a stock third-octave-band graphic equalizer is tuned to.


For a sound engineer, this is a handy tool to seek out the venue’s room resonances (aka “boom frequencies”, which, in a second step, you’ll want to attenuate using your graphic EQ).

The frequency numbers indicated on the picker wheel match the inscriptions found on graphic EQs (which are rounded off heavily). However, the frequencies you’ll hear follow the correct third-band math. Therefore, when the labels say 320Hz, 2.5kHz, or 16kHz, it’s actually 322.5Hz, 2.58kHz, or 16.38kHz.

Protect your hearing! Don’t expose yourself to sustained volume levels in excess of 85db. Also note that pure sine tones at high frequencies are unnatural to your ears and might cause per­man­ent damage. Use prudence!


We’re looking forward to hear from you:  E-Mail

Release Notes

03/11/11 V1.0 Release.
03/27/11 V1.01  Bugfix: Reacts more consistently to incoming calls.
Bugfix: Recovers gracefully when the on/off switch is flicked agressively.
10/7/13 V1.21  Overhauled for iPhone 5 and iOS 7.
Fixed a bug that rendered the high frequencies at a wrong pitch on some devices.


© 2011 Jürgen Völker. All rights reserved.