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.