I'm in a position where I need to install monitor speakers in an extremely awkward spot, above a sealing (out of sight for the public) behind - and very close to - the microphones on stage.

The microphones are pointing about 30-40 degrees away from where the monitors are allowed to be placed. Since I don't want to loose too much headroom before feedback kicks in, I'm looking for monitors with a narrow coverage angle in one direction, so I can tilt them slightly away from the mics.

The only type of speaker with such a directional characteristic to my knowledge is a line-array segment, and the smallest of these I could find is the OmniLine from Martin-Audio. However, I'm looking for a single (active) unit for the price of an Omniline wall mounting bracket ($300,-).

I also found some SoundLazer and Acouspade ultrasonic things which are interesting, but not available in any shop near where I live, and I'd like to hear them before giving it a shot (sounds a bit too tinny in the video demo's).

I'll be shelving off most bass to prevent resonance in the sealing, so bass response is of little concern. The sealing is quite low, so they don't need much power.

Does anyone know of affordable active (monitor) speakers with such narrow coverage characteristics?


After getting the answer I learned allot more about the type of speakers I was looking for. Some keywords can help anyone else looking for something similar. The type of speaker is usually called "column array" or "vertical array" speakers.

The extremely expensive models come with software that allow to aim or focus the beam of sound to specific angles. This is done by adding delay to individual speakers using Digital Signal Processing. It works according to the "Huygen's principle". Delaying the middle speakers will create a strongly focused wavefront, beaming to the center, while delaying the outer speakers forms a wider angle wavefront spreading in a more spherical manner.

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A portable line array kit with a mounting kit may be your only answer. Something like the a pair of HK AUDIO E435 with the install kit. I personally have a set in this configuration, and I've used it as house speakers/monitors combo where they were behind the performers and facing the house. There was little to no feedback from them except at the lower frequencies because the subwoofers are point sources, but I always roll off the low end on the mics. Now, my setup was farther away from the mics than what you may have.

Like I said before, line arrays will normally give you more headroom before feedback because of the nature of line arrays - many low SPL point sources with lower chances of getting in phase with the mics vs. one high SPL point source in phase. Here's a demo of what I mean, but with much more expensive speakers.

For you the HK Audio's may work (they are based in Germany) for you because of you budget.

  • Thanks! Super! exactly what I'm looking for! The K-array KZ12 also look great and have an angle of 20 degrees vertically according to the specs, but since I'm working out of sight I guess the E435's with an angle of 70 degrees might perform just as well. I guess the angles might be more similar than the specs show, depending on the frequency and decibel-threshold used to determine that angle. Is there a standard or do they all just generate their own specs based on self-picked threshold and frequency? Oct 4, 2014 at 11:58
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    I don't know for sure. It seems to me the ideal is for them to make the vertical coverage angle as close to 0° as possible. That way you can truly direct the sound like you would a beam of light/laser. BTW, I looked more carefully at the E435 specs and they are passive units with 70° horizontal coverage angle with no mention of vertical coverage angle, oddly enough. I believe you wanted active units, so the E435 may not work for you. The K-array KZ12's are not active units either. You may not have a choice in the matter of active units if you want something small. Oct 7, 2014 at 6:49
  • You're right, I'll be looking at some E435's coming Saturday. There is room to experiment with the coverage angle by rotating them, and maybe placing the speakers deeper into the sealing with some insulation beside could help. The amp will probably not fit in the space when fixed to the speaker so some soldering or alternative connectors will be needed. I'm also looking at other line-arrays, but most are hard to get, or extremely expensive. The most exotic ones I found are from japan (not what I'm looking for, but amusing). Thanks again. Oct 7, 2014 at 20:31

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