Active Portable Line Array

Active Portable Line Array


Designer:
SRL Loudspeakers

Project Category:
Loudspeakers/Cabinets

Project Level:
Intermediate

Project Time:
8-20 Hours

Project Cost:
Over $1,000

Project Description:
This project entailed building two (2) 12″ powered line array style PA speakers utilizing the best materials, components, and construction techniques.

Design Goals:
Build an enclosure that had very high SPL, power handling, and excellent fidelity. Maintain small size and weight while still having relatively low Fb and high SPL. Utilize line array wave guides for minimal vertical dispersion and greater on axis response.

Driver Selection:
Part # 290-589

Part # 290-527

Enclosure Design:
Enclosure was designed with two (2) separate chambers: the woofer chamber and the compression driver chamber. This made it much easier to prevent leakage through the wave guides or attenuation face plate. Box volume was 1.75 cubic feet with an Fb of 53Hz.

Enclosure Assembly:
5/8″ Baltic Birch plywood. Entire enclosure is held together with beach-wood biscuits,staples, and glue. This method while taking longer actually ensures a stronger bond and zero chance of vibration and resonant frequencies from fasteners coming loose.

The only fasteners that were used were 10-32 T-Nuts and grade 8 SHCS’s to hold the drivers in place. Truss head screws were used to mount the Penn-Elcom handles and jack dish into place with foam gasket around the flanges.

Crossover Design:
Dayton Audio PMA800DSP 2-Way Plate Amplifier 800W 2-Channel with DSP and Bluetooth – 1,500 Hz Crossover

Conclusion:
While this project was very time consuming, it yielded a product far superior than any big name PA speaker that could be purchased. We utilized the finest materials, construction methods, and Eminence Drivers for a high quality product. This design is very unique in the sense that there are next to no PA speakers in the line array format using wave guides like this. These speakers have such controlled response and significantly high output that they can be set very far from the audience without the high frequency breakup associated with standard wave guides. These wave guides only have 10-15 degrees of vertical spread which results in next to no ceiling or floor bounce. This gives the end user more flexibility when setting up a venue.

About the Designer:
SRL Loudspeakers (founded 2017)

We were founded on guitar iso-cabinets and quickly moved into designing and building sound reinforcement cabinets for DJ’s and mobile musicians. While lead times aren’t our selling point, our quality and tonal characteristics speak for themselves.

Project Parts List:

Dayton Audio PMA800DSP 2-Way Plate Amplifier 800W 2-Channel with DSP and Bluetooth – 1,500 Hz Crossover
Eminence Kappalite 3012HO Neo 12″ Speaker Driver
Eminence NSD:2005-16 1″ Neo Titanium Horn Driver 16 Ohm 2-Bolt
L-Pad Knob and Faceplate for 3/8″ Shaft
Parts Express Speaker L-Pad Attenuator 100W Mono 3/8″ Shaft 8 Ohm
Speaker Cabinet Port Tube 3″ ID x 4-1/2″ L

10 Comments

Add yours
    • 2
      Chris Lambert

      David — Thank you for the compliment. In regards to your question, it’s more of a hybrid of single cabinet used in a line array. The type of wave guides used in this assembly have only a 10-15 degree vertical spread like those used in line array cabinets. The purpose of this project was to make a cabinet with more of a point source style with the highs being completely focused vertically. They have a very wide horizontal spread, these particular speakers can throw much, much further than a typical exponential horn. The beauty is that there is next to no ceiling or floor bounce. You’re probably right that the title is a little misleading. My apologies.

    • 4
      Chris Lambert

      EC — you are not missing anything, the wave guides were not purchased through PE and I wasn’t sure how to list them due to this. They are manufactured by “P-Audio”. What you see are actually 2 wave guides, and two line array horn lenses. Behind that are two (2) 16ohm 1″ Eminence compression drivers wired in parallel to the amplifier.

  1. 5
    Roy Novio

    Nice project, I would like to build a couple or maybe 4 cabs for even longer throw for those large venues. I am a DJ and make this my next project I have 4 sound system that I chose to keep in my arsenal. But this is a big curiosity for me, although I am not fond of Eminence drivers one must think how the 12″ will sound with the Dayton amp crossed at 1.5kHz? I have 15 mm BB and the 12″ HO so I only have to get the waveguide and 2005 CD.
    Are there plans available? Thanks again!

  2. 7
    Joe ross

    Two of these stacked one on top of the other with waveguides lined up would be very effective for longer-throw applications. And I have been very impressed with the Eminence Kappalite series! Only suggestion I have is to replace the L-Pad with fixed-value low-inductance resistors that will be more reliable long-term.

  3. 8
    Tim

    The good thing about these is it seems like the tweeters wouldn’t interfere as much if you wanted to stack 2 or more cabs for extra SPL. My Bill Fitzmaurice cabs could do with this sort of waveguide in them.

Leave a Reply to Joe ross Cancel reply