our chruch new sound system

[saramack]

The room is 80ft long by 80ft wide with a valted ceiling starting at 20ft and peeking at 45ft. We are placing the following sound system in and I will explain how we are doing it. I greatly welcome any and all imput.

(2) JBL vrx 915s 18s (non-powered) 800 watts at 8oms
We will be running them with (1) Crown xls 5000 (1100 watts per ch at 8oms.)
(4) JBL prosound 2way mains (600 watts at 8oms)
We will be running them with (2) Crown xls 5000 (1100 wats per ch at 8oms.)
(2) mackie s408 2way 4x8" rear house mains (600 watts at 8oms.)
We will be powering them with (1) qsc plx 3602 (750 per ch at 8oms.)
(4) seperate monitor mixes (with existing eaw and peavy monitorsl)
We will be running these with (2) Crown xls 802d 500 watts per ch at 8oms.)
All of this will run through a A and H gl2400, DBX DriveRack eq, Art 30 crossover, BBE 882i, Furman AR 20 II for all power amps and a Furman P-8 pro II for all other ac power such as wirless units.

We are planning to place the subs one on either side of the stage with two Jbl prosounds sitting at head level above the subs. The mains will be sitting side to side in a so that they are not facing streight out toward the house. They will roughly be at a 10 degree< to the house. The subs will face streight out. Mid-way back we will be placing the Mackie 4x8 one on either side of the room to help with the displacment of the front mains. I am not sure if a delay is needed with such a small room. any help here would be great. The walls are sheetrock with 1.25" foam padding and the ceilings are plywood. Our budget is 15 to 18K. The budget may help explain why we have chosen the above speakers. If there are any other thoughts please express them

Thanks.

[Gracetech]

Are you recycling any of this gear?
Got any pics of the room?(i like pictures)
What style of music?
What SPL do you hope to generate?(A weighted please)
What is your stage dimensions?

First off i would try to get the Mains up a ways so that you are not killing your front row. Even if you lift them 10' in the air. You will want to tilt down your mains as well so that the bulk of the sound goes into the audience and not bounding off the back wall. I don't thank you should go with Delays but that's just a guess going off of your room dimensions and nothing more. If you do need a delay i would suggest getting the processing to handle the delay. The idea on system integration is to keep the voices to a minimum and if you introduce a new voice that is just out of time with the main voice you will lower your intelligibility. Of course the delay of the monitors bouncing of the ceiling will cause this effect as well but we can cover that later.

Collect a bit more data and get back to us.

BTW Welcome to CMN!

crt

[waynehoskins]

Welcome aboard!

My first thoughts are generally in line with what Chad said, except that my preference would be to delay the rear fills. I've been told it's not necessary from an intelligibility standpoint for distances less than 50 feet, but it's amazing what even delaying the main PA to the stage will do, only about 5-10 feet, for transparency.

So yes, get the PA up off the ground (20 feet is a nice convenient number that comes to mind) if you can. There are some free softwares out there (Meyer's MAPP comes to mind) that will let you model the space with some stock set of loudspeakers in various places. The goal is to get moderately uniform coverage across the majority of the seats.

Not knowing JBL boxes well at all, my gut instinct is that you have more power to the tops than you need and not enough to the subs. At my church, which is a similar size except we have a drop tile ceiling at 12 feet, the main arrays are two boxes each side of Renkus CFX121 with one channel of Crown MT600 driving each box, and the subs are two EV MTL1X with a bridged MT2400 driving each, and the power distribution is about right. That sort of relative power seems to work out pretty well in many cases.

The other thing that jumps out is that, especially if the PA is wide open, one 20A electrical circuit isn't enough. Our amps are balanced on three circuits and never have we tripped a breaker. In the old days on a similar-sized crappy PA, with the amps on one circuit we would trip a breaker every now and then -- I think just in the Furman.

The analog crossover and EQ and BBE thingy seem extraneous with the Driverack (DRPA? 260? 480?). I think there are better options for system processors than the DR series too (BSS Soundwebs come to mind) -- there are many great DSPs out there, and it should be easy to pick one that's a good fit for your PA, application, and future flexibility. The one we have, for example, makes it possible to almost seamlessly integrate a "lecture" mixer as well, even with an automatic cutover. Still working on implementing that, but it's a piece of cake. (current bottleneck step: repair the lecture mixer)

Of course we still need more information, but those are my initial thoughts.

[saramack]

Thanks for the imput. First, the speakers that are up now are hanging about 20' the proplem is that they are overshooting the first three rows. the angle is good I think that they are too close to the front row. They are hanging right at the edge of the stage which is about 50wide. x 20 deep. Since they are hanging that high I am thinking it would work to move them back a few feet the throw should still overshoot the stage but not the front rows. Then the mackie 4x8s can take care of the back (with or without a delay I am still thinking about that.) The music style is contemperery for the most part but some live bands will come in from occation playing stuff like United, Chris Tomlin, Delerious and the like. If need be, we can bring the youth sound eq over for the concert feel for those events. I will upload some pic today if I can get them. We where going to use the DR 260 but that can change. I will check out the BSS.

Please offer any other imput you can.

Thanks.

[Brad Weber]

Could you maybe provide a little background on how you came to develop this particular complement of equipment? What are you trying to accomplish? What model are the JBL mains? Did anyone look at speaker locations and factors such as coverage when selecting the speakers noted? Is this equipment already purchased or on hand? Is the 50'x20' stage within the 80'x80' room dimensions, thus resulting in more like a 80' wide by maybe 55' deep listener area, or is the listener area 80'x80' with the stage outside of that.

I am a bit confused on the mains. You initially noted that you planned to have two JBL's per side at about head height (on stands?). But your latest post discusses some existing flown speakers. Is the intent to abandon or reuse the existing speakers? What are they and what about the existing system needs to be improved? Has anyone looked at the existing system to optimize it or see what might be done to improve what you get from the existing system?

As far as specific issues, I'm not sure why you feel that fills are needed. If fills are needed then with an 80'x80' room you probably need more than one on each side, the room is really too wide to be addressed with a single fill on either side side wall. The Mackie S408 with output that rivals the mains, a nominal 75 degree by 40 degree pattern and no provisions for a wall mount also seems an unusual choice for a side wall mounted fill speaker, but perhaps there is some specific reason it was selected.

How did you see the DR260 and ART crossover working together? As Wayne noted, there may be some overlap there. On the other hand, I do not see enough processing to support stereo mains, stereo subs and four separate monitor mixes. Did anyone sketch out how everything will interconnect? Maybe you could reassess the system processing and you might start by skipping the BBE Sonic Maximizer.

Is a single 15" sub per side enough? Also keep in mind that split subs can create a 'power alley' with high low frequency levels in the center of the room and areas off to the sides with much lower levels, a possible consideration when the listener area is wide. Is there any way to locate the subs together in the middle? That would avoid that potential issue and provide up to 3dB additional output due to mutual coupling.

Wayne had a very good point about the power, you are almost certainly looking at over a 20A load during some use and probably needing two or even three 20A circuits just for the amps.

That also segues into another area, that of the actual installation. Have you considered practical aspects such as power locations and capacity, cable paths, mounts, equipment space, etc.? Have you included all the related hardware, cable, racks (if necessary) and so on in your budget? Who is going to be installing the system and then adjusting and tuning it? Just want to make sure that such considerations are being properly addressed and don't become problems or surprises later on.

[Gracetech]

Hey Wayne i was talking about killing the Delays altogether. In a throw that short you can just hit it from the front and be done with it no need for a delay ring. If you do put in a delay ring i would absolutely time it correctly with the mains, which is what i was eluding to. 30 or 40 feet are perceptible to me and drive me nuts.

crt

[saramack]

Hi Brad. Thanks for all your imput. I will try to answer all of our queations and addresses.

How did I come to this choice of equipment... I have used a similar setup in a similar setting before. It worked well.

What are we trying to accomplish... We only have two jbl prosound 2ways flying at about twenty feet and hanging over the edge of the stage. That's it. Nothing more. This is why we are using the jbl prosounds. We already have them. I could get different speakers, but these are good for our cause. The rest of the equipment has not been ordered yet. So changes can be made. The 80x80 is including the stage so yes it is 80x50.

Where we will be placing the speakers... Yes, I was thinking about setting them at head level; but I have since changed that thought. I will fly them along with the subs. We are making an attempt to better the sound by replacing the current lack of a sound system. the existing system can not be optomized because it is not a system.

Why are fills needed... Because with the front speakers flying and angled so the front half of the house gets the sound it needs, the angle prevents the rear house from getting the sound it needs. The mackies where chose because they are set on a curced face not flat. So the speakers are somewhat dule directional. And for there pirce.

How do I see the DR and art working together...In the past we have only ran the subs through the crossover. We found we get more out of the subs when we can devote all the art to them. So in a since, they are two seperate issues.

Please explain why I should skip the BBE. It is a good way to punch the subs and mains seperate from one another. I have no problem dropping it but I need to know why.

Is a single 15" sub enough... The jbl vrx is a 18" speaker not a 15" but, yes it is possable to relocate the subs to the middle. If it works better, I am all for it.

Wayne had a good point... Yes I am aware of the power needed. I have 300 amps devoted for lights and sound. I plan to devote 80 amps to sound.

Have we conisdered power location etc... yes we have the location where we need them and the cable paths are ran. They where ran when the building was built. The mounts are in place and the ones missing we will put in. All of this is under controle. Yes all cables, hardware and racks etc. are ready.

I look foward to your further help and input. I hope I answered all your points and welcome any and all insight and suggestions.

Thanks.

[prochlea]

Have you bought the VRX yet? If you aren't flying them, you probably don't need the VRX model. The MRX is the same speaker, just without the flying hardware... and cheaper

[saramack]

We where going to fly them but, we are still in the planning stages. Are you sure the mrx are the same as the vrx? If so that explains why the srx cost more then the vrx unpowered. I did not look. I will check into it. The proble with useing speakers you hav never heard is the fact that you have never heard them and the shops around here don't carry them. I am planing to buy most of the system from B&H as I have used them in the past and turst them. An other suggestions would be great.

Thanks.

[Brad Weber]

Originally Posted by saramack

We only have two jbl prosound 2ways flying at about twenty feet and hanging over the edge of the stage. That's it. Nothing more. This is why we are using the jbl prosounds. We already have them. I could get different speakers, but these are good for our cause.

What are the speakers? I am not familiar with a "prosound" model and the specs for the mains could be very important.

Originally Posted by saramack

Why are fills needed... Because with the front speakers flying and angled so the front half of the house gets the sound it needs, the angle prevents the rear house from getting the sound it needs.

The problem is that with a listener area 80' wide and 50' deep, one fill speaker on each side will not really help, especially if you are running stereo. You would probably need several speakers across the width of the room to have an effective fill system. And that would be for a mono system, try to have stereo fill and the potential issues get even worse. If the speakers themselves are acceptable then I would really try to see if the mounting heights and aiming angles could be modified to improve the coverage.

Originally Posted by saramack

The mackies where chose because they are set on a curced face not flat. So the speakers are somewhat dule directional. And for there pirce.

They are not dual directional, in fact the nominal 75x40 pattern for the horn is narrower than most speakers and the configuration with multiple small drivers and somewhat larger horn provides more pattern control at lower frequencies. Many people also seem to find the S408 lacking in the lower mids, but you might be able to compensate for that, as well as trying to match the mains response, if you have dedicated EQ for them.

Originally Posted by saramack

Please explain why I should skip the BBE. It is a good way to punch the subs and mains seperate from one another. I have no problem dropping it but I need to know why.

The theory of the Sonic Maximizer is that speakers introduce phase and amplitude distortion so it introduces even more distortion that is assumed necessary to compensate. The problem is that modern pro speaker manufacturers and system designers go to great lengths to eliminate such issues in the first place. A Sonic Maximizer also does not necessarily mesh well with crossovers, for example how do the frequencies the 'LO Contour' control affects match with your crossover and does it end up trying to apply a single correction for two very different speakers and conditions? The general consensus is that these devices may be fine for individual source processing and production but they have no place in a good live sound system.

Originally Posted by saramack

Is a single 15" sub enough... The jbl vrx is a 18" speaker not a 15" but, yes it is possable to relocate the subs to the middle. If it works better, I am all for it.

You noted that the subs were the JBL VRX915 and the VRX915S is a single 15" sub, the VRX918S is the single 18" version.

[waynehoskins]

Originally Posted by Gracetech

Hey Wayne i was talking about killing the Delays altogether. In a throw that short you can just hit it from the front and be done with it no need for a delay ring. If you do put in a delay ring i would absolutely time it correctly with the mains, which is what i was eluding to. 30 or 40 feet are perceptible to me and drive me nuts.

crt

(Hey Chad, I was down your direction earlier today, Georgetown, but I didn't have time to swing farther south.)

Oh right, got it. Yeah, I agree, it shouldn't need a delay ring. There's enough ceiling height to get the arrays up high enough to not need it. Maybe a centerfill, maybe frontfills, but that's about it.

The reasons you don't want a sonic maximizer are too many for me to remember and express, but the core is that a sound system should be linear from console output to listener ears. A sonic maximizer is terribly nonlinear: it introduces all kinds of harmonic and phase distortion in the name of "sounding good". And my email just told me that Brad beat me to it.

A proper system processor will handle all necessary processing well. The only thing you might add is a graph in front of it if you have touring groups in; you'd leave the graph flat for you, but it lets the road engineer tweak the overall frequency response of the PA without having to mess with the DSP.

Any particular reason you're partial to JBL loudspeakers? There are many other excellent choices out there that you may be overlooking.

A model of the room and loudspeaker system would be a very good investment of your time. Without that, you're pretty much shooting blind.

[saramack]

hi again Brad and all.

Thanks for all your imput. I want you all to know that I am listening to everything you guys are saying. Given our budget and the fact that I am the best choice we must do this on our own. So any and all adivce will be greatly taken.

Given the general thought about the BBE, I will drop it. Thank you guys.

From my best understanding the JBLs are a line somwhat like the SRXs. They are 600watts at 8 oms and weigh about 90 lbs. They are 2way with a 15" speaker.

As far at the fills on either side, no problem. I can place them across the room and use 3 instead of 2.

I understand about the mackies and will replace them with a better suitted speaker. What would you suggest at around the 5 to 600 price range?

As far as the jbl 15" or 18", My typo. I make a lot of mistakes. They are 18"s

I wonder if placing the subs and mains in the front middle of the room with three fills across the back would be better? what are all of your thought on that? Any and all help is greatly taken.

Thanks.