Another Line Array Speaker Thread

dhenryp

Member
2003-08-03 12:52 am
Mass.
I’ve finally “finished” my line arrays using my DIY ribbons (see: http://www.diyaudio.com/forums/showthread.php?s=&threadid=50162). I say “finished” because the crossover is currently a junk box1k first order. I’ll probably build a more formal passive second order as a temporary measure until I complete an active crossover. The ribbon is a 47” seven segment ½” true ribbon. The main cabinet is sealed and has 14 – 4.5” PE Vifa buyout mid/woof (P/N 299-432) in a 4-3-3-4 taper. The main tower is East Indian Rosewood with Satin water based Poly finish while the tweeter box and base are black lacquer. How does it sound? I just finished it last night and have limited time on it but like it a lot. The Vifa’s have surprisingly good bass and the tweeter sounds clean and extended. It has a crude crossover and I’ve made no measurements yet so you can assume my listening impressions are highly with colored DIY builder pride. It’s my first line array and first ribbon (in fact it’s my first full range DIY speaker).
 

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dhenryp

Member
2003-08-03 12:52 am
Mass.
Cal - Thanks for pointing out the corner I missed. I'll get right on that:)

Paul - you are right abought the lacquer. It takes a long time - and just to site in a dark HT:rolleyes:

Mark - my next project is to paint the house. I'm thinking of doing it in black lacquer:D

Seriously, after the tempoprary second order, I'm building an active fourth order plus three chip amps to drive each speaker (one for the ribbon and two for the mid/woofs). This probably won't get done before the winter.
 
Hi Mallick and Tyimo,

Thanks for the complements. Jim's white paper was the bible for calculating aspects of the line array like line lengths and inter driver spacing. Anyone building or contemplating a line array should become familiar with it.

I'm not sure when I'll get back to serious tweaking/measuring - I've gone off to other projects for a while.
 

dhenryp

Member
2003-08-03 12:52 am
Mass.
We would obviously need a lot more information about drivers, sizes, distances to start to give an informed opinion, but ,in principle, a curved line baffle aimed at a listener in a fixed position would work. In fact I remember this exact thing being published in the old Speaker Builder magazine probably 5-6 years ago. You could great imaging by focusing the arrays. The disadvantage is that focusing the arrays so precisely on a single spot gives a VERY small sweet spot - the person sitting in the chair next to (or the person sitting in your chair who is significantly shorter or taller) would be listening to a quite different sound.
 
Tyimo said:
When we solve a problem than we get another new one....

The "solution" there is the head-vise missing from your illustration. :)

There was an article in Speaker Builder (IIRC by the Liberty Instruments fellow) on a focused array. I have also heard Terry Olson's -- his are really quite amazing, even more so when you consider the "no expense barred" approach he took ;)

I have a pic somewhere -- can't find it...

dave