Audio system design for 600sq M

Hi everyone, first post so hello from me.

I'm trying to design a loudspeaker system for a climbing wall, the total area is approx 600sq M that needs to receive a reasonable quality sound.
I've had a look through google and I can't find much information on the design of the overall system, clearly there is alot of specific box design etc... (which will be great in a few weeks when I'm making them...) But I'm really having trouble getting information on the system as a whole.

I would be looking for a directional speaker system because we want the people climbing to hear the music but if you are in the cafe etc... then you would not be bombarded by thumping techno hahah. Are there any articles or guides you know of that I could read to give some insight into the design of public audio systems?

At home I have a NAD 3020 amp and some Mission m70 speakers, great for my room but probably not loud enough for a climbing wall. I'm going on a hunch that the system in the climbing wall will be very similar, the only difference being the total power consumtion!? Would that be about right, or is there more to it?

AS I say i'm really clueless so anyhelp would be greatly appreicated.....

Even to begin with I don't know what sort of power the amplifier should be rated at, my NAD at home is 28W @ 8ohm, so going on that I'd have thought that something like 500W @ 8ohm would be ideal... What do you think?!

Thanks, Will.

Well, I recon this is a Tony ASS question.

But just for starters, realise that Bass is omni-directional, containing and directing it is not easy.
Your mid and top frequencies can be dispersed in, "Beams" by cabinet design. IE 60/40 degree dispersion.

Over to the experts.

First things first, Is it your intention to put the speakers in the wall, or only aim a system at it?

For comps we set up a scaffold tower in the centre of the hall with speakers under the tower firing at the wall and climbers area...

Quite a lot of dust in the system after though, so have a regular (weekly?) cleanout. Chalk for the hands gets all where.

Hi, have got some more information over the weekend as I didn't have much to go in my first post... here goes;


Some Criteria;

I have a budget of approx ~ £300 - £400

Make a sound system for a medium sized climbing wall, total climbing area is ~ 600 sq. M.


The building is a large warehouse which is being shared with another company, due to this at times we will want to be able to turn the bass down so as not to disturb the other occupier, however at weekends we will want it thumping!

The required inputs are;

Tuner
Microphone
3.5mmm jack
Laptop/PC
CD player

Set up;

I've spoken to a couple of friends who have suggested slightly different ideas on a theme

a) Inputs > Pre Amp > Amp > Speakers – The pre amp would allow me to select different inputs but not allow me control the volume of the bass vs mid / high speakers?

b) Inputs > Mixer > Amp > Speakers – Will the mixer allow me to turn down the bass speaker without affecting the mid/high speakers volume?

Equipment;
going on advice

Mixer = £60?
Haven't decided on a model etc.. yet but I'm informed there not too pricey and power isn't an issue because there on the signal side.

Amp =
2 channel, 500W RMS per channel @ 8 Ohm ~ £130 ish

Speakers =
2 x 12” mid high drivers 300W each £120
1 x 15” bass drivers £ 100

cabling = speakon connectors and some cable as yet undecided because I'm not sure on length of run.. £50

How would I wire the amplifier up with 3 speaker cables and only 2 speaker outputs on the amp, I guess if I wired the bass driver and the mid and high onto 1 channel and only a mid/high on the other channel it would unbalance the system?

Would it be better to have a separate amplifier for the bass speaker altogether? If this was the case would it be a requirement to buy another bass driver so I had one for each of the amplifier output channels ? Or would this be over the top for my needs?

Sorry if I have asked lots of questions, there is so much variation and I feel a bit lost!
I haven't really started looking at equipment yet properly, I had a quick browse and I think I can afford all the bits at a reasonable quality I thought I would try and make a list of the equipment I needed and then shop around to acquire it.. Second hand etc... ebay...

thanks for taking the time to read, any input would be great!!

Will

and a picture of the proposed layout

Edit: Tony Ass: The speakers will be aimed at the climbing wall, see diagram. The position of the speakers is open to suggestion I just put them on the diagram where I thought would be suitable!

Edit 2:

Change of plan, Initially I'm going to build 2 MT 130's that I've found on the plans section. I will power them from a 400W per channel amplifier, this should be adequate as the bass drivers are 300W and the tweeters are 80W. The Amp input will come from a pre amp with cd / tuner inputs. I'll KISS to begin with and if we feel the need for more bass then I can upgrade at a later date.

will.

you'll get no bass from an mt130. better off buying some cheap reflex cabinets and dotting them around.
the climbing wall i use have a pair of extremely cheap skytek cabs hidden in the rafters and an even cheaper amp driving them. the setup is adequate as they never seem to crank it right up.

@ Cudds : When you say I wont get any bass, I'm not sure I follow, looking at the bluearan website they are offered as a bass / mid low driver?? I would of thought they would produce quite alot of bass!? no? I guess the thing is were coming from different areas, no bass for you would most likely be a lot of bass to me haha!!

Well, got the purchasing eyes, last night I bought a QSC RMX 2450 ,

750W into 4 Ohm per channel. I was reading a lot about sizing of the amp for speakers and the general consensus was the amp should be roughly 1.5 - 2 times as powerful as the RMS rating of the speakers, so if I'm gonna build MT130's that's approx 380W a channel @ 4ohm, so I figured this amp should suffice!! On that note has anyone got any recomendations for passive crossovers? or do you build your own with a 1st order / 2nd order pad?

Also got some sweet news that I have some more money to play with, so I was thinking about making a bi amped cubo 12 so supplement the system. Whadda ya think?

many thanks, Will.

just wrote a long post but deleted it by mistake! smiley11

with the mt130 it is the horn that will stop you getting bass, not the driver. it will only support loading down to about 120hz.
a bass reflex cabinet will allow lower response (around 60hz) for a smaller package and prob be plenty loud enough.

what drivers are you looking at?

the beyma passive xovers seem good. saying that, fane have a few current designs with passive xovers tailored especially for the cabinets... www.fane-acoustics.com/downloads ... rapres.pdf
www.fane-acoustics.com/downloads ... ure_12.pdf
www.fane-acoustics.com/downloads ... ure_15.pdf

you dont need to worry too much about doubling amp power as recorded music has a lower dynamic range. that rule is more for live sound where peaks of 10db or more can be sent to the amp.

haha I've done that before myself a few times...
So the drivers I was looking at were the recommended ones with the enclosure; the BMS 4550 and PD 121... sorry I'm a bit unsure which part your referring to as the horn, reading your response it sounds like your referring to the whole enclosure? However I thought the horn was the plastic part that screwed onto the tweeter (sorry I'm not so good with the terminology yet)
Would you mind explaining a little about why it will limit the response to ~ 120Hz? I thought that the horn was there to improve the coupling of driver to free air, but I didn't think it would limit the drivers ability to produce lower frequencies? Just looked at the data sheet for PD121 and it's range only starts at 100Hz...

The links you posted to the Fane website looked great and I prefer the price!! thanks alot, I only had one question from looking at the PDF's.... now this may sound stupid but;

In the 12" reflex enclosure the 2 drivers being used are;
Crescendo 12MB
and CD 150...
So I looked up the driver impedances and their both 8 ohm, so if they were being used with a crossover they would have to be wired in parallel, (is this strictly true?) and so two 8 ohm speakers in parallel is 4 ohms. However the PDF from Fane clearly says its an 8 ohm speaker cabinet! This really confuses me! Unless the crossover has a 4 ohm input impedance, but then this would be a very poorly designed filter no? baa. Sorry if this is a really stupid question but I'd like to clear it up! Thought I'd got this clear.

thanks alot, Will.