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[Matthias Heitzer]

 The percieved equal sound distribution is often a result of the broad dispersion and reflexions from walls and ceiling and not of the geometry of the array. 

[Brad Weber]

The percieved equal sound distribution is often a result of the broad dispersion and reflexions from walls and ceiling and not of the geometry of the array.

This leads to the topic of direct versus indirect sound, the resulting coverage versus intelligibility and why achieving both acceptable coverage and acceptable intelligibility can be such a challenge, particularly in difficult environments.  To achieve a system with good intelligibility for all listeners the general goal is typically to provide good, and equal, direct coverage for all listeners while also minimizing the energy hitting other surfaces, thus maximizing the direct-to-reverberant energy ratio at the listeners.  And you want to do this for all frequencies of interest.
 
A column or compact line array may help limit the vertical pattern and thus reduce the sound hitting the ceiling, which could indeed be beneficial for intelligibility, but I'm not clear on how it would resolve any front-to-back coverage issues.  And since these devices typically have broad horizontal patterns that often also vary significantly with frequency, there may be some aspects related to the horizontal pattern to also consider.  I'm not saying they may not be a good option, just that you'd probably need to look at it in more detail.

[Matthias Heitzer]

(Oh, there are a few lines missing, i have somehow overwritten them:
For 1kHz, the nearfield for a 1m array ends at ~1,5m, you might gain distance with a halfspace placement, but only
for low frequencies where the nearfield is a lot smaller. No way you can use the popoluar -3dB at double distance with such small arrays.)



Actually you're rather running into trouble, because the line source can work for the highest octaves and the resulting tonal difference from first to last row can't be compensated because there is no practical way to drive small elements of the array individually.
But the proposed model has nasty lobes above and beneath the main axis in the mid and high frequencies, what indicates a very poor coupling in the upper octaves.

marketing doesn't solve real world problems

[Scott Hofmann]

(Oh, there are a few lines missing, i have somehow overwritten them:
For 1kHz, the nearfield for a 1m array ends at ~1,5m, you might gain distance with a halfspace placement, but only
for low frequencies where the nearfield is a lot smaller. No way you can use the popoluar -3dB at double distance with such small arrays.)

Actually you're rather running into trouble, because the line source can work for the highest octaves and the resulting tonal difference from first to last row can't be compensated because there is no practical way to drive small elements of the array individually.
But the proposed model has nasty lobes above and beneath the main axis in the mid and high frequencies, what indicates a very poor coupling in the upper octaves.

marketing doesn't solve real world problems

On the other hand, having actually heard the MA12 in a real installation, they can work very well for spoken word and reasonable music levels. Admittedly it was in a much larger space about as wide as it was deep. And, they were set up as two columns high on each side. Clearly, one's mileage may vary.

[ProSoundWeb Community]