P.A for Carols by Candlelight

[spazmatik]

Hey guys, im a student and have an assessment which requires me to design an audio system (P.A) for a Carols by Candlelight which will attract 1-2000 people. There is a set band that consists of drums, bass, elec and acoustic guitar and a keyboard. There will be 5 soloists which are backed up by a 30 peice choir. This will be an outdoor event, so there will be uncontrollable variables such as wind and other misc noise.

Ive figured that ill need a desk with a minimum of 24 channels and have decided to go for the Allen & Heath ML 3000 for FOH and utilising the Allen & Heath WZ16:2 for monitors. Does anyone know how much RMS i'd need for an outdoor gig like this? Ive estimated around 7-9000w RMS.

The band will be mic'd up like the norm and am planning on using condensors for the choir by having a pair of cardiods in a spaced pair position and also having another mic placed in the centre to fill in the field.

For FX ive gone for the Yamaha SPX 990, DBX 1066. As id need to tune the FOH speakers and monitors ive gone for the Rane DEQ 60 Dual 31 Band.

I need to know if my RMS estimation is alright, so i can then i can make a decision on my FOH speakers. Im still not sure wether to go for a ground stack set up or line array. Im kinda leaning towards the line arrays, as they have greater dispersion.

Am i doing ok guys? Thanks for any help.

[Jim vanBergen]

Hi Spaz, (got a real name?)
By RMS I'm assuming you are talking power, but specifying it the wrong way. What do you really want to know, where are you (state, country?) and...what is your PA?? Consoles draw very little. Backline is usually a couple of 20amp circuits. Your PA size is the question. You will see, if you do a search, a very similar thread recently (you might search Matico) and see similar responses. But for outdoors, when specifying a diesel generator, what you are suggestions is quite small- a 7000 or 9000 watt gennie is a couple of 15a circuits. You want to look at large portable gennies that spec power in KVA. Look at Cat Power or United Rentals and you'll see what I mean.

With more information, we can help you better. Let me ask you this, though-
Why do you want to only have 16 channels for monitors with a 24 channel FOH console? As I see it, you'll be needing all 24 channels in both locations, and more if you want to use those FX processors. I'd spec two identical consoles (personally, I'd go higher up the food chain if this is a project with no set budget) for FOH & Monitors. Don't forget a two way transformered-iso split and appropriate snakes.

Hope this helps.

JvB

[spazmatik]

Hey Jim, yes i do have a name, Clayton. Im from Sydney, Australia.
Thanks for replyin I think i might come off askin the wrong questions. Because im planning an outdoor gig, and the venue is a soccer field at a local sports ground. I wanted to know how much watts my P.A should be roughly to cover 2000 people? Am i asking that correctly? So taking that into consideration i can make my choice of speakers. Im assuming a gig like this will crank around 95-105dB SPL, which then i'd need at least another 10dB above that to cover my headroom.

Great point about the FOH/Monitor Consoles, well this isnt set on any budget, being as cost effective as possible is also in mind. Ive gone back and figured to use the TAC Scorpian 32ch both for FOH/Monitors.

Could you suggest any sort of P.A for a gig like this? As i mentioned in the earlier thread, im kind of leaning towards a Line Array which at least 2 15in subs. does that sound correct to you?

[63hz]

ring some production companies in sydney

they will have set systems to do the gig and will just need to know venue size, est crowd, and power available and a few other things that they will ask

No offense but your a fair way off the ball to pull off a gig of 2000 people, i wouldn't recommend 2 15inch subs for 100 ppl in a pub.

With a Line array you will then have to budget in rigging or lifters

brand names of mixing desk won't a difference unless the bands you have playing have certain riders that need meeting. (but most high end soundcraft, midas, a & h, yamaha will suffice)

And when you say you want 105db, where do you want that? at FOH, at the boundary of soccer feild,
i know in melbourne i've been stuck with some council regulations on SPL limits at the edge of my venue.

I've done FOH and monitors for several Carols By Candlelight in the past few years
ranging from 2000 to 10,000 people

As an Example the large one had 2 40ch FOH desks (running at the same time)
and a 32 ch Monitor Desk
The Second FOH console was for a full orchestra (so you wouldn't need that)

But there are a lot of places in sydney that do this all year round and know what gear and systems will work

[Larry Elliott]

+1 for what 63Hz says

[fifthcircle]

TAC scorpion? Can't say I'd be too thrilled to be mixing a show on one of those- especially as a monitor board.

You've gotten some good advice here. Rely on your PA supplier to get a good rig for you. If you have a couple thousand, you don't need a huge rig, but a small rig won't cut it. Something like one of the smaller line arrays would probably work really well for you (I've used rigs that range from a Dynacord Cobra to a QSC wideline for that number of folks with great results). A decent digital board will help by saving scene memories with your gain structure. If you prefer analog, go for a standard PA desk, not a recording desk. This can range from Yamaha or Soundcraft to Midas. At FOH, a matrix can be a very useful thing- if for no other reason than to distribute audio.

If what has been described here by myself and others isn't making sense, consider either passing on the gig or hiring a PA company that you can ride to get you what you need without your understanding.

--Ben

[bishopthomas]

The words "student" and "assessment" lead me to believe that this is another case of a school project and not an actual gig. Maybe we should change the name to HomeworkSlutz...

[Roland]

Well as this is some sort of school/college project, I'm not going to go into too much detail, it's for your learning to do the research kind of defeats the object if we tell you all, but a couple of pointers are here if you want to take advantage of them.

For starters, I wouldn't spec a rig like this with an old or out of date console. Chances are this sort of gig would as likely be on Yamaha LS9 or M7. 95-105db spl is way over the top, it's a carol concert not Van Halen, probably around 85 at the mix position would be closer. Line array/point source, it doesn't matter, both have strong points. It's about coverage and ultimately how much they want to spend. Systems are specified as SPL coverage or number of boxes, RMS wattage means nothing, I've heard (and used) 10,000 watt systems that can provide sound with a rock band for 5.000 + people at a pinch. I also know of systems that would use 4 times that to achieve the same output spl. Guesstimate 3-4 tops a side plus equivelant subs to do your job.

That's the rough, you can work out your own power factor from that.

Roland