We are fortunate to have lots of high quality equipment available to us for making acoustics measurements. We regularly use EASERA from AMFG for making impulse response measurements in rooms and to measure reverberation times and other useful acoustical parameters. Recently, we also have been using the AudioTools iOS app developed by our friends at Studio Six Digital for amazingly high quality measurements using only an iPad – a traveling acoustician’s dream!
However, all of these measurement approaches usually involve using a loudspeaker to create the test signal. Sometimes, the sound of the loudspeaker in the room is exactly what needs to be tested. Other times, we would rather have a sound source located where musicians are located, and a loudspeaker is either not readily available or really is not the best representation of the musicians’ sound anyway…
Enter the Big Red Balloon.
This humble device has been used for direct measurement of room impulse responses for a very long time. It’s reliable, loud, highly portable, and has good frequency response way down to the 63Hz octave band when you blow them up really big.
Did we mention loud? It is important to remember hearing protection and also to be sure that anyone who might be nearby knows that it’s just a Big Red Balloon going “bang!”
Here is a fun sequence of images showing this in action: