Any published line array designs?

[mazeroth]

It seems like for a while line arrays were the speaker to build. However, I have never seen a published design for a pair of line arrays in the two years I've been into speaker building. I'd think there would have been some by now, but after searching and searching I've come up empty handed.

Also, has anyone built a "good" pair of dipole line arrays? I know a lot of dipole NSBs speakers were built, but I was curious if anyone ever built a pair using more expensive drivers?

Thanks!

[thylantyr]

People that do this for business reasons probably don't
want to share their passive crossover, but usually they share
the drivers used and you can look at the design for ideas.

Given the fact that there arn't many tweeter candidates suitable,
you end up seeing the same tweeters in line array designs.
For midrange or midwoofer, the choices are wide open.

If you run an active setup, synergy between a good tweeter
array and midrange can be found easily.

You really don't need published designs, make your own.
Find the tweeters first, the rest becomes easy ...

[mazeroth]

Thy,

I'm an active man myself. I was just wondering if anyone had posted a passive line array design.

I was considering the PT2 tweeters from Parts Express, but after reading Jonh Krutke's review of them, stating how they're one of the worst tweeters he's ever measured, I'm not so sure if that route is feasible. Are you EQing your line arrays? I know you also have some VERY expensive planar drivers and was wondering how the PT2 stacks up to them?

Thanks.

[roger_lew]

Have you seen these? They are not dipoles, but they do use more expensive drivers.

http://www.partsexpress.com/projects.../Kuze3201.html

[thylantyr]

Originally posted by mazeroth
Thy,

I'm an active man myself. I was just wondering if anyone had posted a passive line array design.

I was considering the PT2 tweeters from Parts Express, but after reading Jonh Krutke's review of them, stating how they're one of the worst tweeters he's ever measured, I'm not so sure if that route is feasible. Are you EQing your line arrays? I know you also have some VERY expensive planar drivers and was wondering how the PT2 stacks up to them?

Thanks.

The PT2 assessment is correct, but also there is mention of
of an already known fact. An array of PT2 is amazing as distortion
is significantly lower vs. the individual driver at the same SPL
level.

If you want success with PT2 then;

1. Use eight to twelve per tower.
2. Steep crossover slope. I use the digital crossover
at 1.71khz, LR 8th order.

Because it's active, fine tune that crossover point as needed.
If I crank up the tunes to extreme levels where people are getting
punished, I will raise the crossover higher to take the edge off.

If you are designing for maximum SPL, wire the PT2 array
for the lowest impedance and get a good amp. I drive my
array at 0.8 ohms per channel.

EQ? I use the presets in the digital crossover to create different
settings for the system as a whole. Mostly I attenuate midbass
and midrange down a bit, different levels of attentuation are
stored in memory. I do this to customize the sound experience for a particular genre of music, song or listening mood. Real time
tweaking is your ally.

An big array of PT2 wired for low impedance has alot of hidden
potential and when you look at the cost, it's a bargain vs.
store bought speakers. You'd have to spend $20k-$40k to
get a commercial line array to equal it or beat it, anything cheaper
in the store will not offer the SQL potential, not even close. {unless you have great horn speakers : }

[mazeroth]

Hmmm...You say the distortion of an array of PT2s is significantly lower than a single driver. Whenever I read about line arrays they always say you don't couple the planars/ribbons when it comes to SPL, as they have minimal vertical dispersion. So, in theory, when you're listening to an array of planars you're only really getting a good listen to the one that's at ear level, right?

Now, then there's the doubling of distance -3db an array gains over the -6db a normal point source exhibits. This would lower distortion as the planars would only require half as much power to play as loud as a single planar.

So in the end, what you're gaining is that the planars only have to play with half as much input as a single planar would require, which would drop down distortion. My question is, how much less distortion is there when you half power?

Thanks for the input this far. If anyone else wants to chime in, feel free

[karma]

im about to start a set i e-mailed this guy for his plans. nothing yet, he mailed back saying there in auto cad format and if i still wanted them. i never got the plans

http://home.earthlink.net/~ferretantics/linearray.html


just waiting for my 94 monsoon drivers to come in

with the lack of info on the net im going to publish my findings

there going to look like this pic


cheers

[Geek]

Originally posted by karma
http://home.earthlink.net/~ferretantics/linearray.html

I wonder why the SPL is so low?

[chainenoble]

maybe someone can correct me if i'm wrong.did zaph not do the tests 1st order @1000hz.but the suggest xover is 3order @2500hz pt2.wouldn't any tweeter have alot of distoration if crossed over so low?thus if the pt2 was crossed around 2500 would the distoration not be much lower??

[zenon]

To be a proper line array there are a few guidelines which must be obeyed. A good rule of thumb could be that It's not possible to make a proper line array using *only* "round" drivers (typical tweeters or the small mids shown above). Of course you'd use them for the mids but @ high frequencies you need to use some kind of planar tweeter.
James Griffin wrote a paper which covers the basic mechanics of how line arrays work (I am by *no* means an expert).
http://www.audiodiycentral.com/awpapers.shtml