MATT - The ASC Acoustic Test Signal
....play it first over headphones and then in your room. You hear a scale of rapid tone bursts that any HiFi system should be able to reproduce. Your system could but it can't because the room keeps getting in the way. Then concentrate on the sound stage. It's a mono signal and the image should stay stage center, tight and focused. But it doesn't.
This test is a rapid gated slow sine sweep. It demonstrates the musical clarity vs frequency of the HiFi system in your room. In some ranges of sound you will hear strong rapid dynamic sound level changes while in other ranges the tone bursts blur together in reverberant chaos. You can also hear the more familiar peaks and valleys of your room. Then play it again but this time close your eyes and concentrate on the sound stage of this perfectly mono signal. In some tone ranges the image stays put; stage center, small and tight, where it belongs. But the next tone range sees the image lose focus and fluff up into a ball of fog. And yet another sees the image up and wander off, flying around the sound stage like Peter Pan.
The objective of performing the MATT test in your listening room is to determine where you might move your speakers, listening position, and/or where to add acoustic treatment to your room to obtain the highest quality sound possible from the components in your listening environment.
To explore the musical intelligibility and the sonic image-ability of your audio system...
How fast is your room? Most audiophiles know how loud they can play their room before it begins to breakup. Even the speakers have a breakup threshold, above which we begin to hear cone breakup and box buzz. The MATT test is an easy way to ring out your room without risking doing damage to structure or gear due to sustained power at one frequency. At lower sound levels it checks out the room acoustic part of your listening experience, sorting out clear dynamic bandwidths from blurred bandwidths.