BillFitzmaurice.info

Charles Jenkinson wrote: but not to play country.

'Cause if you do, you might attract some barefoot hillbilly who will go fishing with dynamite in your tank trying to catch him some supper!

bitSmasher wrote: wouldn't the air mass in a fake cab cause issues with a working sub underneath it?

It would.

Don't agree with this. I think any (almost) completed cab without a driver+amp may eat bass, potentially lots of it. If you must add fakes, make sure there is no full horn path. Close the fake horns at or even before the first corner.

If I may add my 0.02 in the currency of your choice:
When you are willing to go through all the trouble to build fakes, why not run the last few yards as well and make them real cabs. Sooner or later it will be known or rumoured that not all cabs are real. No good for your reputation. Better to have them all flap the pants of the punters (and avoid cancellations due to insufficiently separated subs).[/quote]

+1

I know with high end stereo speakers superfluous non-functioning speakers can eat bass, but I was thinking that the massive output of 8 t-60s would dwarf 4 dummies. I stand corrected. I also believe that if you're going to put in dummies, it's a bit of false advertising, false bravado that isn't necessary with these behemoths! Go big, all the way, and actually have what it LOOKS like you have.

I would try and install something that highlights the movement of air e.g. a small fog machine and fan laser.

I've wanted to do this, but maybe with a strobe light. Experiment with what freq of flash corresponds to what bass frequencies.

hifibob wrote:
The center of the stage (DJ booth area) is 10x12.. The 2 platforms are for the dancers/performers.. The space on the outer edges of the stage will be where the the cage holding the DR's will mount..

Yes 4 more tubas go under the center of the stage, So there will still be 8 functioning tubas side by side like the original plan..

If that's your arrangement, you may want to make sure you've got the amp channels and processing to delay some of the outer subs to the center pair. Your line is getting long enough it may cause cancellations out to the side of the array. If I don't do that with my t48's all in a line the drop off is very notable.

All in a line like that is just like any other line array. In this case the horizontal dispersion is tight, almost parallel lines from the row of cabs out to the audience. One benefit here (if you want to call it a real benefit ) is that you're pushing a single wavefront and lower extension is available. Think of it as being able to lowpass the T60s @ 16 Hz.

Hifibob, When you light this puppy off, remember to log on to the USGS website and see if you are showing up on their network of seismometers!

Why would you need to delay the outer row of subs? The mouths all line up with each other, and the signal is going to all the cabs at the exact same time, so they are all outputting the same freqs at the same time. I can understand if the room is large enough and you have subs at the back of the room, but why in this case? Trying to learn.

Aye and delaying the outside cabs can widen said dispersion, as well an maintain more forward directionality

Is this something I'd have to worry about with 4 T48 standing up next to each other? Not that I plan to run them that way, but thought I'd ask.

Unlikely. it might narrow the dispersion *a little*, but not like the 20 foot wide stack of T60's

That's good news. Thanks, Sine.

miked wrote:Is this something I'd have to worry about with 4 T48 standing up next to each other? Not that I plan to run them that way, but thought I'd ask.

It's only a problem once the width reaches more than one wavelength. That's no issue with subs, but unavoidable with mains.

so at 8 feet for the t48s, no issue. but the 20 feet for the T60s is definitely an issue above A 55hz.

sine143 wrote:so at 8 feet for the t48s, no issue. but the 20 feet for the T60s is definitely an issue above A 55hz.

+1, though it wouldn't be all that bad until perhaps 100Hz. It's the monster sub arrays 30 feet and wider that you sometimes see that reveal that the operator probably doesn't even know what a wavelength is.