What is line array loudspeaker and its application ?

What is line array loudspeaker and its application ?

Summary

Line array speakers can also be appropriately hung, aimed and bent in accordance with the specific shape of the performance location, which can provide outstanding sound quality performance to most audiences.


Because line array loudspeakers have several very practical characteristics such as uniform horizontal coverage, strong vertical directivity, and low sound energy attenuation in the radiation area, they are gradually replacing traditional loudspeaker arrays in many sound reinforcement fields. For sound reinforcement at the same volume in the same place, the line array speaker system may be smaller, lighter, and easier to lift.

Line array speakers can also be appropriately hung, aimed and bent in accordance with the specific shape of the performance location, which can provide outstanding sound quality performance to most audiences.

Line array is not a line source

  
The line sound source is composed of a series of drivers with equal distances. The prototype of its initial application was produced in the 1850s, and it was originally designed to improve the intelligibility of speech in the reverberation hall. The use of line sound source is based on its very small vertical pointing angle. If its vertical direction is 0 degrees, this is what we call a "cylindrical wave". Whenever the sound source distance doubles, the energy of the cylindrical wave will attenuate 3dB, but the sound source distance doubles the energy of the "spherical wave" will correspondingly attenuate 6dB.

The actual work of the line array

  
The outstanding ability of the line array lies in its ability to provide uniform sound pressure coverage from the front row to the back row of the auditorium. The sound pressure level from the back row to the front row is almost the same.
The loudspeaker used in the horizontal array is designed to compress its spherical radiation waveform into a pie shape, such as 60°x40°, 90°x40° or other similar designs, so that it can provide good coverage for the sound reinforcement of the venue. If it is directional to cover a small area, you can align the speaker's radiation principal axis to the rear row and align the –6dB attenuation angle to the front row to obtain uniform sound pressure coverage.

If the height of the hanging point is sufficient, the position and angle of the speakers can be fixed so that the distance from the first row to the horn is half of the distance from the last row to the horn. At this time, the discrete control ability of the horn itself to its radiation angle can well balance all of this, so that the front and rear fields can get consistent and uniform sound pressure coverage and effects.


Functional requirements of line array speaker modules

  
When we combine the acoustic requirements of line sound source coupling and the benefits of the "J" shape in practical applications, the design goal of the line array speaker module becomes clear.

  ●The playback range of the full frequency band.
  ●The unique driver selection and cabinet design require that the center distance between the cone drivers be less than 1/2 wavelength below the crossover point.
  ●For the part where the center distance between the units is greater than 1/2 wavelength, the waveguide is required to provide a straight or very narrow vertical direction (<10°).
  ●In order to produce a continuous wavefront, the exit height of the waveguide must not be less than 80% of the height of the speaker module.
  ●With minimum size and weight under the premise of allowable output power.
  ●Simple, fast, safe and reliable hanger.
  ●Simple, fast and clear line and signal routing process.
  ●The matching array design software can easily set the length, position, pointing direction, and bending angle of the array. At the same time, provide the correct coverage relationship prediction for the venue.
   ●The use of multiple units in the designated frequency band (the audible range of the human ear) requires the horizontal distance between the units to be as small as possible to provide continuous radiation diffusion in the playback frequency band.