Bi-amping help

[Kilowatt]

Ok, here's the problem:
The crossover frequency is 500Hz. There is 7200W RMS bass power and the subs total 105.4dB/W@1m. This should produce a loud (I suppose dangerous) 144dB peak SPL. The rest of the spectrum is covered by some 500 - 10,000 Hz horns rated 100W RMS and 106dB/W@1m each. How much power should go to the horns? How many horns?

Thanks.

[walker]

Kilowatt, I'm starting to get the picture here. We're not talking to a classical music enthusiast would want's 20dB head room, your playing with the big boys aren't you? This is a sound re-enforcement system you're building isn't it?
It helps to know where you're coming from, the rules change even though they shouldn't.
This comes from the Yamaha book on sound re-enforcement, the 50/50 power split occurs around 300Hz, at 500Hz the split is something like 60/40. I like to keep a little more in reserve for the top end, 50/50 wouldn't hurt, it just wouldn't be as economical.
These ratios get are VERY dependent on ambient acoustics, (indoor/outdoor). Also the ratios take speaker efficiencies into account and yours seem pretty balanced so I would start at 50/50-60/40.

With regars the number of horns, they will need to match the power used. It's often advisable to add a 20% margin. By the way I make the bass output around 141dB, (105 + 36, but I'm not adding acoustic coupling which varies greatly). Beware some manufacturers like to quote system power when rating their mids and tops.

I hope that helps some.
Regards WALKER

PS I'm curious, you in a band? Where's the rig going to get used?

[Kilowatt]

It's moslty going to be used outside or in large buildings. It's main purpose will be just as an expensive little toy that will let me play music at over 140dB. It's a big sound system, what can I say? Also, I have some friends in a band who may or may not be interested in buying such a thing.
Now, the sensitivity of the two sets is not going to be even close to balanced. The subs are 96.4dB each for sensitivity. All 8 of them would be 105.4 because you add 3dB each time you double the number of speakers. Just one horn is 106dB sensitivity, so the whole set of horns will be more sensitive. It's easy to figure it out for 50/50. 8 horns and 800 watts would be 50/50. (10log800)+115=144. The 8 horns would measure about 115dB sensitivity. The total SPL of the ENTIRE system would be 147dB in that case. Am I right? If my method of figuring this out is wrong, please let me know. What if I want to split it 60/40? I don't know how to figure that out.

[Edited by Kilowatt on 11-18-2001 at 10:45 PM]