What is a Line Array Speaker System?

by Andrew Bishop

A line array speaker system is typically a string of passive or active (powered) speakers hanging from a truss, winch or beam, either side of a stage designed to deliver quality, clear and loud enough sound to an audience.

There is a debate on who invented line array but it first appeared in the early 80's in a primitive form but has progressed greatly in the last 40 years.

Why use a line array system over point source PA systems (stacks of boxes on the stage). What is the advantage of Line Array speakers?

  • Line Array is very directional and is suited to audiences who are seated or don't move great distances from a fixed location.
  • Line Array allows you to deliver an equal level of quality sound in equal quantity to the front, middle and back row of the audience.
  • Line Array properly set up directs the sound to the audience and not bouncing around or reflecting off the walls and ceiling.
  • Line Array cabinets properly aligned act as a column speaker vertically with a long throw that spread sound horizontally.
  • Line Array is a string of cabinets linked together with metal hardware allowing you to angle each speaker to cover selected parts of the audiences leaving no area without sound.
  • Line Array attends to the directional frequencies greater than 100Hz. Subwoofers take care of the low frequencies as this sound is not directional so they sit in front or just under the stage.

Line Array can take a lot of time to set up correctly, allow a full day if you are touring venues that are not known to you. Many touring bands prefer point source as you can set up in minutes but this tends to be for audiences less than 3000 people.

Are Line Array speakers active or passive and which is the best?

Active line array speakers have a dedicated amplifier built into every speaker in the array.

1. Active Line Array can only be used inside unless each unit is waterproof

2. In a live gig if a module goes down you cannot correct the sound easily without climbing up the array so some of the audience will get upset.

3. Passive line array gives the engineer precise control of each cabinet and is the preferred choice of 80% of sound engineers driving a desk with multiple bands on stage.

What is the best size of speaker for Line Array?

The most common line array speaker size in Europe is 8" although 4" and 6" are ok for smaller venues. The dual 8" array with throw 350 metres outside under normal conditions and is considered the optimum choice for PA rental companies.

How do you use a Line Array? Twin arrays with 4 cabinets in each array with dual 18" turbo subs is considered the best package. Drive this system with 2 x 4 channel 10kw amps one for the tops and one for the subs. A speaker management processor controls the frequencies delivered to the arrays and the subwoofers.

In Africa and India 10", 12" and 15" Line Array systems are deployed but for western ears and our music these systems can sound muddy and lacking in clarity due to the speed of response. In fairness these are often only used for the spoken word such as speeches and worship. Not rock n roll.

What to look for when buying a line array?

  • Check the individual cabinet hardware is certified and approved with CE markings
  • Ensure the hanging frame is approved and certified
  • Check the drivers are easy to change and are freely available not pricey specials.
  • Ensure there is "No Gap" between each cabinet as it is hung.
  • Pay attention to the weight.
  • Study the manufacturers warranty and after service.

 

If you are considering a line array system free and unbiased advice is available from bishopsound.com - simply email or call.