Array Me in the Right Direction [message #18176] |
Fri, 14 October 2005 22:15 |
Cuppa Joe
Messages: 103 Registered: May 2009
|
Viscount |
|
|
Could someone here please guide this amateur to a forum which covers arraying horn-loaded systems for pro audio sound reinforcement? (I'm already acquainted with Mr. Fitzmaurice's site, by the way.) Vertical, horizontal, point-source, whatever. Pro & Con arguments are both welcome. My many thanks for any input!
|
|
|
Re: Array Me in the Right Direction [message #18177 is a reply to message #18176] |
Sat, 15 October 2005 07:37 |
wunhuanglo
Messages: 912 Registered: May 2009
|
Illuminati (2nd Degree) |
|
|
May I suggest going to JBL Pro and reading their papers and application notes on their Vertec system? Compare that with say EAW's stuff and you should have a pretty complete picture. Pro Sound Web (www.prosoundweb.com) is a good user site. FWIW
|
|
|
|
|
Re: hmm [message #18181 is a reply to message #18180] |
Sun, 16 October 2005 10:13 |
Cuppa Joe
Messages: 103 Registered: May 2009
|
Viscount |
|
|
Yes, I've found good reading in the past on the Meyer Sound website. Hey Mike, that other link looks like it'll be a fun read! Thanks, man! However, I'm still trying to dig up reasons and opinions as to why the horizontal, horn-loaded curved arrays of the past are in the dumpster. It's been suggested, even when horn-loading mid/high paks so there's an almost complete segregation of coverage angles between sources, that the concept still doesn't work. I have an interest in arraying some DDS 2-25 horns (25 x 30 degrees) in 25-degree traps over a yet undetermined midbass section. The idea seems straight-forward enough to me, but I've been told that it won't fly in the real world. (The Nexo reprint I have doesn't really explain why a well-designed HF horn--properly crossed--in a matching trap would exceed its coverage angles so severely that it would degrade the entire array's performance.) Comments, please??
|
|
|
|
|
|
Re: Array Me in the Right Direction [message #18185 is a reply to message #18176] |
Wed, 19 October 2005 16:05 |
Todd W. White
Messages: 16 Registered: May 2009
|
Chancellor |
|
|
Most of the line array stuff is pure hype. When discussing this issue recently, a friend of mine put it well when he said: "People seldom need the power density that a line array can provide, and almost never have a seating area that is the right shape to be covered by a line array. And you can't just stick a pair of them side by side to widen the coverage. Most projects can't fit a tall enough line array to have a broadband line array behaviour, so in the frequency range it would really help (80-250Hz) most of the line arrays used aren't line arrays at all." Referring to the ad hype, he said: "At least they generally haven't included the old Meyer B.S. that promoted the idea that the sound could go out so far and then just drop off. Line arrays just keep going and going and going, except for excess atmospheric attenuation of course. "I never hear that issue addressed when people claim 500'+ of coverage without significant level loss, maybe at 500Hz, but the 4khz will be sucked up by the air by the time you get that far away, and a good bit of 2khz too. The last time I actually used a line array it was a stack of 4x 203B/290's in a Giant Voice system. Even if you can get true line array behaviour and make the wavefront cylindrical rather than spherical, you can get the drop off in level down to -3dB/doubling of distance, but the excess atmospheric attentuation doesn't change, it's still something like -8dB/100ft @8kHz and -5dB/100ft @ 4kHz." I think Barry McKinnon said it rather well...
|
|
|
Re: Array Me in the Right Direction [message #18186 is a reply to message #18185] |
Wed, 19 October 2005 19:51 |
Cuppa Joe
Messages: 103 Registered: May 2009
|
Viscount |
|
|
I've also wondered in the past how the short-throw horns in some line array designs could get the HF to the back of a concert venue. However, for the most part, I have nothing against line arrays, as they have their place in pro audio. I was mostly curious about why the horizontal, arced point-source systems had mostly disappeared. Based upon the recommended reading and responses, I've arrived at two conclusions about horizontal VS line arrays: 1)You can't get away from imperfections in any arrayable system (such as lobing error and comb-filtering, etc.), but most are less obvious in vertical line arrays. So, you have to be more careful about the design compromises you choose to tolerate for the horizontal. 2)Since horizontal tight-pack systems aren't truly "point-source" because they can't actually emit from a common locus, your choice of components and their arrangement becomes more critical than with vertical arrangements. It seems to me that redesigning the horizontal tight-pack array of olde is more of a challenge than it is an impossibility!
|
|
|