$250 MTM Vertically Oriented Measurements

What would happen if we take that MTM speaker and turned it on its side? I did just that, by modifying my high-tech stand with another piece of wood and some tape. It may not be pretty but it’s for the science, right? I dropped a Center Stage acoustically transparent screen down behind the speaker. It didn’t affect the acoustics and I could get better photos.

In the 1/24 octave chart below, we can see the effect from rotating this speaker vertically. The horn tweeter isn’t as happy, exhibiting worse off-axis response from 4 k to 10 kHz, but you can see the frequency response from the midrange drivers shows much less wave interference.

If we look at the same slice at 1244 Hz to compare its lobing to the horizontal orientation, you can see from the below chart that for the specific frequency it was successfully eliminated. I won’t be showing any more of these charts because while they show the lobing shape more clearly, the 3D charts have more color. That must be a good thing.

To better gauge the audibility of orientating the speaker vertically, the chart below shows the measurements with 1/6 octave smoothing. The horn is clearly not designed to be rotated 90 degrees, but by not having horizontally arraigned redundant drivers, we have improved the smoothness of the speaker’s off-axis response a great deal. In the midrange drivers’ frequencies, the standard deviation improved to 1.19.