SPL Society

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Hey everyone, I just wanted to share with everyone a few of my plans.
Basically me and a friend at Sussex University have decided that we are going to start a society based on the following ideas:
-Building a fully functional, high power, high quality PA system
-Throwing Free parties in Brighton, events at clubs and at both Unis
-Having a place where DJs can meet and share songs, interest and teach people who are playing with the idea of trying their hand at it.
-Gathering all Audio enthuisiasts in Brighton together, to compare systems, Hifi, mods, etc

So its going to be very DIY orientated; we will be funding it all with personal cash, hopefully the Uni will help out and and money made at events.

Thats about it, so if your in or around Brighton area then give me a shout! Or if your on ye Olde Facebook, check out this:
Girls should make the first move, and that first move should be a sandwich. Boxes | Facebook


Also if anyone has any experience with this sorta thing, I am very open to advice and any help I can get.

Cheers,
Will
 
High Power... Well I want at least 20KW of bass bins and corresponding amplifiers, erm, a good 10KW for mids and another 5KW or so for highs?
I don't really know to be honest, that's a very long term goal.
The TI chips sound interesting though, I'm going to have to look at that, is that 600W into 8Ohms?
My current Kit consists of some custom Cabs with some 15" drivers that I can't identify; they're called "Eminence Decimators", and I think a company called Custom Sound had something to do with it. They also have two Motorola Piezo tweeters per speaker.
For an amp I'm using a Matrix UKP1000, which isn't quite fully working, there's distortion on one channel.
 
High Power... Well I want at least 20KW of bass bins and corresponding amplifiers, erm, a good 10KW for mids and another 5KW or so for highs?

Where do you plan to plug that lot in? You can get 3kW out of a standard double socket, so maybe work on that? As a thought, a system with a 12" mid-high cab, with an 18" sub per side (properly horn loaded for maximum efficiency), each with it's own 600w amplifier. You'd be going places then... It'd certainly be enough for club use.
 
1kW into a good bass bin is a lot.
1kW into a horn loaded bass is more than a lot.
1kW into each of a pair of stacked hornloaded bass is even more than an awful lot.

2kW into a pair of 90dB/W @ 10m listening distance is going to satisfy most audiences indoors.

There is no need for 20kW.
 
No need?
Explain this:
Valve Sound System

If I was using it in a club then yeah, your right I wouldn't need that ridiculous amount; however I'm going to be throwing some pretty big free parties in Brighton, in big open fields, where I'm sure that a stupid amount of power would come in handy. Maybe 10KW is still a bit of an exaggeration though.

Didn't realise you could only get 3Kw from a wall socket.. Hmmm, many wall sockets? :p

It is all in planning stage right now so this is all good information, cheers guys.
 
Yeah, 13A fuses, x230v = near enough to 3000w.

PA Systems - something to read.

Put it this way, 100w and a pair of 12" speakers will be at talking volume 100m away (outdoors, but near a building). More speakers = more projection, especially when stacked vertically.

By stacking the speakers vertically, you limit the vertical dispersion, thus improving projected SPL (it's no longer omni-directional). I proved this theory to myself when I put the 12" cabs one on top of the other. The only problem was, due to the interaction of the tweeters, there was a very small "rip your ears off" zone, where there was a horrendous amount of treble. The solution: disconnect one of the tweeters!

Anyway, working to 3kW ensures your system can be used anywhere. Constantly blowing fuses isn't particularly good to listen to, and replacing the fuse with a 6" nail is plain dangerous.
 
these two statements show you are way out of your depth.
I hope some of your colleagues have some safety sense.

Dude, that doesn't need to be said. Plus it was a joke, hence ":p"...
I'm new at this and want to learn exactly how to do this, I've started it as a project with a University friend to try have some fun and act as a learning experience.

Chris, cheers for the advice. I knew stacking provides some improvements but I wasn't sure how..

As it seems that high power is a lot less necessary than I thought, I think we may focus on high quality and efficiency instead.

Was also wondering, if wall sockets only provide 3KW, how do this big mental rigs in say, Fabric for example, or Digital power their rigs?
 
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Stacking cabs used to be the way it was done in the 80's and early 90's, but there's far too much interference when done UNLESS the cabs are designed to array together (much easier said than done). That's one of the reasons why line arrays became so popular. If you are going to use a regular point source cab, then delay zones are your friend. :)
 
Delay zones are separate speaker systems located further out in the room, field, etc. These speakers are time-aligned with the main systems to maintain volume and intelligibility from the front of the audience area to the back. It can be one speaker on either side of the room or a bunch on scaffolding 300 feet from the mains in a field.
 
Yeah, 13A fuses, x230v = near enough to 3000w.

Anyway, working to 3kW ensures your system can be used anywhere. Constantly blowing fuses isn't particularly good to listen to, and replacing the fuse with a 6" nail is plain dangerous.

The fuses should hold for more than 3kw multiplied with 3 maybe 4, as long as it is music and not constant sinewaves. Some modern amplifiers like digam K20 for example also has programmable powerdraw limits. However that amp will actually draw 13A/230v at 18000watt with pinknoise-1/8, see datasheet:
http://pro-audio.powersoft.it/download_get.php?obj=827


BTW, when talking about amplifiers, well: the scale is logaritmic so it will go up very fast... twice the power is just slightly more, ten times is more noticeable...
However, units like TC-Finalizer can add a lot more healthy "percieved loudness" to the sound than multiplying of the amplifiers can...
 
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I had a look at the TC Finalizer 96k; it looks like a damn nice piece of kit! Just I may have to save my pennies.. Or student loan :p.. This is why Im so poor!!

So does that work by converting the sound into digital and then resamples and converts back to analogue? I can imagine that If there is a mixer with a digital output to hook it up to then the improvement would be a lot more.
 
We use both the finalizer 96. And finalizer express at work- theater use.
The 96k is one heck of a powerful processor, but the express is a bit easier to use with fewer options. Not a bad thing for live use where time is precious.
They both work as you said, and the same goes for any true digital processor with analog i/o.
 
Yes, it is digital with adda converters.
But it is the multibandcompression and the tubelike distortion (DRG) that does the trick.
Depending on how clean and dynamic your rig is to start with, you can add up to 10-15dB of percieved loudness with those, but if your rig is bad to start with it wont do any greater difference.
There is also a discontinued unit called Triple-C that also has those functions, but personally i like the EQ and the other FXes that exist in the finalizer.
Also, look for the original finalizer wizard not the plus or 96k, those later ones are more subtle than the original and therefore more suited for studio.

BTW, i tried the express for 5 minutes once and disliked it very badly, the real one or the tripleC is much better.
 
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We seem to be stabbing in the dark here, so let's set some reasonable constraints.

Budget
Audience/area you want to cover
Size/weight of this rig (important for transport costs)

ElectroAudio - there's some mistake with that datasheet. The watts out when running at 13A@230v = 2250, with 763 watts being lost as heat.

The rated power is 18,000watts, sure. But it's never ever going to get there unless you use an alternative power supply.

These delay zones may be something to look into, but it depends on exactly how much area you need to cover. A couple of full-size bass horns and some decent mid-highs would suffice for a large area. You wouldn't need a lot of power either, if you design the mid-highs for efficiency. A 12" mid with a resonance of maybe 80Hz would have an efficiency of well over 100dB. Suddenly, you don't need much power to go very very loud.
 
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