OT: FBT Line Arrays

Discussions about the use and operation of SAC (Software Audio Console)

Re: OT: FBT Line Arrays

Postby Butch » Tue Aug 27, 2013 11:09 pm

Line arrays just like any other speaker system are used improperly probably more often than not :lol:
Just checked out a church install 4 VRX cabs in a single line in the center of a wider than deep seating area and the top 2 were pointed directly at the back wall 20 feet up

Butch
Butch
 
Posts: 107
Joined: Wed Jul 11, 2012 11:41 pm

Re: OT: FBT Line Arrays

Postby soundguy » Wed Aug 28, 2013 2:45 am

randyhyde wrote:Line arrays suffer from a lot of phase distortion that you don't get with point-source cabinets. So yes, they're inherently inferior to point-source speakers.


This is close to being the most utterly foolish comment I have heard on this forum, other than some comments from the Kool Aid crowd praising the genius of the great one. You clearly have little or no experience with line arrays or you couldn't say that.

Soundguy
soundguy
 
Posts: 338
Joined: Thu Jun 14, 2012 7:21 pm

Re: OT: FBT Line Arrays

Postby IraSeigel » Wed Aug 28, 2013 7:55 pm

soundguy wrote:This is close to being the most utterly foolish comment I have heard on this forum, other than some comments from the Kool Aid crowd praising the genius of the great one. You clearly have little or no experience with line arrays or you couldn't say that.

Soundguy


+1
Sorry Randy.
IraSeigel
 
Posts: 213
Joined: Fri Jun 15, 2012 9:58 pm
Location: Bainbridge Island, WA

Re: OT: FBT Line Arrays

Postby Jeremyjo » Mon Sep 02, 2013 9:31 pm

A line array, as it is commonly termed these days, typically made up of several enclosures hung (or stacked) vertically and often with inter-box angles in the single digits, is absolutely a model of massive comb filtering. That's precisely how they work "constructive interference", if you will. Several point source boxes next to one another doesn't make a line array at all frequencies, but at lower frequencies relative to enclosure size and spacing, they do exhibit line array properties.

It is fooling oneself to think of the impulse response of a line array as having no phase interference, distortion, aberration etc. Every listener point will have multiple arrivals from the many elements of the array. That "smears" or "spreads" the impulse response out over time. A perfect line array would not have this problem, but the best we can do is pack drivers as closely together as possible and operate them in a bandwidth that keeps them interfering with one another...
Jeremyjo
 
Posts: 20
Joined: Sun Jul 22, 2012 1:16 pm

Re: OT: FBT Line Arrays

Postby BrentEvans » Mon Sep 02, 2013 9:47 pm

Jeremyjo wrote:It's fooling oneself to think of the impulse response of a line array as having no phase interface, distortion, aberration etc, e.


Again, the oddities happen in the vertical plane, and our ears are oriented horizontally. With line arrays, you simply don't hear the comb filtering.


every listener point will have multiple arrivals from the many elements of the array. That "smears" or "spreads" the impulse response out over time

This is why array design and driver spacing is so very important. If the drivers are close enough to acoustically couple, the time differential isn't audible, but rather is part of the constructive interference which creates the line array effect. IOW, you aren't hearing multiple individual drivers, but the effect of all the drivers coupled together.
User avatar
BrentEvans
 
Posts: 269
Joined: Thu Jun 21, 2012 5:05 pm

Re: OT: FBT Line Arrays

Postby mattseymour » Tue Nov 12, 2013 2:25 am

I've heard line arrays used properly (outdoors and with a large array) where they've sounded superb with excellent even coverage. I've also come across the used like Randy describes, too few modules to work properly (does two boxes really make an array? Certainly so t be anything like a line source) or in low ceilings rooms etc. it's back to the age old problem of the right tool for the job. The smallest array I've seen work well was a Meyer sound setup with a smaller array of 4 boxes used for fill.
mattseymour
 
Posts: 147
Joined: Thu Jun 21, 2012 2:42 am

Re: OT: FBT Line Arrays

Postby kdiamond » Sun Nov 24, 2013 9:04 am

Funny how we came to choose FBT for our choice of PA. I was in Thomann store in Treppendorf. There is a room with many monitors for many brands. To put is simple, old model of FBT Verve 12MA blow all others away by far!!! (There were heavy priced (also biamped) monitors from D&B,EV,Dynacord,JBL,QSC, Seeburg,RCF, DB Technologies ) That's when and why I became interested in FBT. I don't know about Modus, But we own a FBT and we couldn't be more satisfied. They all have custom B&C speakers. We compared Verve 112MA to LA acoustics 12XT and both were extremely close sound wise.

I learned not to read the specifications. Just go and listen to the system. That's what we did, was blown away and bought it afterwards. We also went and audition Master Audio. Specification are great, LAN management too, but would not like to comment the sound.

We have:
4 x Qube QSA 18SA
6 x Qube QSA 112A
6 x Qube QSA 112.0A
4 x Mitus 218SA
4 x Mitus 118SA
2 x Subline 15SA
4 x Mitus 152A
8 x Verve 115MA (coaxial)
2 x Verve 112MA (coaxial)

Br,
kd
kdiamond
 
Posts: 5
Joined: Tue Sep 25, 2012 7:51 am

Re: OT: FBT Line Arrays

Postby randyhyde » Fri Nov 29, 2013 11:36 pm

Saw the same system at another show tonight (two blocks from a show I was doing).
Sounded just as bad...

On another topic, tonight I used four brand-new PRX 715m powered speakers as monitors. Everyone complimented me (without me asking) about how good they sounded. Given my mediocre opinion of the PRX 600 series cabinets, this is a good start for this new line. As such, I think I'm going to get the 718s XLF cabinets as subs to compliment the PRX 625 cabs I'm currently using for the tops on my B rig.
Cheers,
Randy Hyde
randyhyde
 
Posts: 385
Joined: Tue Jun 12, 2012 1:42 pm

Re: OT: FBT Line Arrays

Postby gdougherty » Sun Dec 01, 2013 12:05 pm

randyhyde wrote:Saw the same system at another show tonight (two blocks from a show I was doing).
Sounded just as bad...

On another topic, tonight I used four brand-new PRX 715m powered speakers as monitors. Everyone complimented me (without me asking) about how good they sounded. Given my mediocre opinion of the PRX 600 series cabinets, this is a good start for this new line. As such, I think I'm going to get the 718s XLF cabinets as subs to compliment the PRX 625 cabs I'm currently using for the tops on my B rig.
Cheers,
Randy Hyde

I've seen plenty of desk monkeys at festivals destroy the stage sound on an otherwise decent point source setup. If it's playing recorded tracks with the processing set to flat, then I'm up for blaming the gear. Otherwise, it's much more likely to be the operator.
http://softwareaudioconsole.wikidot.com The start of a wiki. It's slow going and there's a ton of info that should be in there yet.
Biggest item is the Command Reference on how to do most actions within SAC. It's 90% of what you need for UI proficiency.

g is for George
gdougherty
 
Posts: 407
Joined: Fri Jun 22, 2012 5:10 pm
Location: Westminster, CO

Re: OT: FBT Line Arrays

Postby lowdbrent » Mon Dec 02, 2013 9:11 am

I see somebody "went there" with the Danley reference. Danley does a great job at making some loud systems with lots of impact. They also do a great job of marketing minutia and publishing specs that do not mean squat. Take some of their subs for example. They publish SPL specs in excess of 140dB SPL, referencing a frequency above 125Hz. I think it was almost 200 MHz. Then, instead of using the standard 0, -3 and -10 for frequency response, they give a -4. Where did that come from and why is only specified on one speaker in the line? Odd.

I like Danley, but they need to get in line with EV and others who publish real world specs and deliver gear that meets or exceeds those specs.
lowdbrent
 
Posts: 71
Joined: Sun Aug 05, 2012 5:54 pm

Previous

Return to SAC Discussion

Who is online

Users browsing this forum: No registered users and 10 guests

cron