Put Your Room to the Test

Art Noxon, PE Acoustical, and founder and president of ASC, invented the TubeTrap in the 1980’s. It was quickly recognized that these devices improved the musical realism of every playback system with which they were integrated.

However, the difference was not manifest in a “flat frequency response”, as the measurement tools of the day (and to this day!) emphasized. Instead, it was the time-domain performance of the room, encompassed by the terms decay and reverberation, and shown to some extent in waterfall charts, that was drastically improved, and brought tears to the eyes of those blessed with experiencing systems optimized in such a way.

It was not about the steady-state performance of the room or stimulation with clean sine waves. It was about the fast tracking of the room, the ability to decode 1/16th notes and faster, across the entire audible bandwidth, that made for unparalleled musical realism. Transient accuracy, with associated harmonic structure, was the path to true high fidelity.

Building on these observations, the MATT Test was developed to help quantify the dynamic articulation and allow a rapid assessment of a room’s capabilities to reproduce… music. Hence the name, the Musical Articulation Test Tones.

You may already know about this test. You may already know it is freeware, and available for download several places, not least of which being at our online store. What you may not know is that you can perform much of the analysis yourself, at home, and use it to optimize your listening experience.  Read through the instructions below, and then download the test file… and prepare to make some adjustments to your system :)

Enjoy!

Can your sound system play back 1/16th notes at 120 bpm? Sure, your speakers can play it, but does it reach your ears clearly? Well, here’s the definitive audio test for the HiFi listening position, the ASC MATT audio playback test. It’s a 7 in 1 listening test. You’ll find you can’t listen to more than one thing at one time, even though in reality varying combinations of these separated listening experiences are going on all the time

1. First, you listen and concentrate on how the sound level varies over the first 5 octaves of sound. This is in effect sounding like the common sine sweep frequency response curve.
2. Play it again but this time concentrate on the clarity or blurring in the articulation of the staccato 1/16th notes as they play up and down the scale. Play it louder or quieter, explore how the musical quality of your playback setup varies with loudness.
3. Play it again and this time concentrate on imaging, the stability and focus of what should be a fixed and dime sized center stage image throughout the first 5 octaves of sound.
4. Play it again and this time concentrate on the sound of the attack transient* of each tone burst, a tick-thump type of sound. It will begin to disappear well before the staccato blurring effect takes place.
5. Turn the volume up and this time listen outward, opening up to sounds from the room itself – sympathetic tones, rattles, drones and tinging sounds that are not coming from the speakers but are coming from the sympathetic vibration of walls, floor or ceiling, cabinet doors, book shelves, windows, panel doors, lamp shades, vases and decorative art.
6. Turn the volume up, stand near a speaker and listen to it working. You’ll find that the box will buzz here and a hum there. Because the tone burst is so short, there is no risk of damaging the speaker.
7. Play it again, a number of times, and each time vary the loudness of the playback. At quieter levels the playback seems just fine but above some loud level the playback seems to get out of control. Back the loudness down a bit. Just below this out-of-control sound level is the maximum listening level for your system, essentially how fast you can go. In very good rooms this might be as high as 95 dBA but most can run in the 85 dBA range while some (lots of glass) rooms run as low as 75 dB.

*The MATT signal is a 1/16th second tone burst followed by a 1/16th second period of silence which ends with the beginning or attack transient of the next tone burst. What you hear isn’t the tone, but something more like a “tick-thump” type of sound which precedes the tone. This is the attack transient of the tone burst. As early reverberation and reflections fill the 1/16th second of quiet time preceding the onset of the next tone burst it raises the noise floor and masks or covers over the lower level leading edge detail in the attack transient. This masking effect reduces the listener’s ability to perceive the shape of the leading edge of the tone burst, the tick-thump begins to disappear and all we hear is the tone burst itself. This loss in the perception of attack transient detail occurs before any sense that the staccato of the notes are beginning to blur together. The information in the attack transient is what makes the sound from a particular instrument sound distinctly like it comes from that instrument. It puts the musicality into the music.

A complete discussion of the MATT test can be found here: acousticsciences.com/matt

The MATT test can also be purchased on CD