This signal is a killer for bad boxy rooms.Įach file is recorded as a mono WAV file at a 44.1 kHz sampling rate. With a little practice you can tell some things about the frequency content of the reflection. It contains enough power to be quite audible, and is excellent for finding those surfaces that may be a problem, such as rear walls and balcony fronts. It's a short (13 ms?) flat spectrum chirp that repeats every few seconds. For example, if you'll set up your console so that the usual feedback culprits (mic inputs) are just on the verge of feedback, and then play one of the fast moving swept sine wave files (especially the one second sweep from 30Hz to 4kHz) over the loudspeaker system, you will likely hear the most problematic feedback frequencies ring out prominently.Īnother fun one was contributed by fellow CSC member, Dale Shirk. If your loudspeaker system has some particularly sensitive feedback frequencies, the swept sine waves can be a real help in finding them. I think you'll be surprised at what you hear.

Even better, put a subwoofer or a floor monitor in a corner of the auditorium and try it again. Or if you really want some entertainment, feed some of those really low frequency sine waves over your loudspeaker system and then walk around the room listening for the room modes and nodes. If you have a TEF, you already have this signal. It's actually a unique pink noise signal created specifically for use with the TEF analyzer. Note: The 'TEF' version of the pink noise may or may not be useful to you. (Be careful to pull the master fader down before you make that adjustment so you don't hurt your speakers or someone's ears!) If you have a sweepable EQ, set the boost/cut knob for maximum boost or cut, and sweep the frequency. Burn them onto a CD or save them onto your USB jump drive or your iPod so that you'll always have ready access to them.įor example, if you're wanting to teach yourself or your tech team what the channel EQ is capable of on your console at church, feed the pink noise into a console channel and listen to what happens to the sound when you make adjustments to the EQ settings on that channel. Download them to your own computer, or to the computer at the sound booth in your church. These commonly requested test signals can prove invaluable, so we have provided them on this web page for your convenience.

Audio test tones download