[RNRGAGNE]

Sorry don't know how to fix it but it's basically a graph representing what he said.

[JohnR]

Here's your thread on avsforum:

http://www.avsforum.com/avs-vb/showthread.php?p=20354100

Here's what I get when I model two drivers in 200 liters each (purple) - compared to IB (black) with 300W per driver:



I'm not going to post the excursion graph but I'd say it's reasonable - if you want to be sure that you stay under Xmax then drop power to 200W per driver.
 
Will you melt the drivers with 200/300 W each in a large sealed box? I wouldn't have thought so, but don't hold me to it if you do....

If your electronics are up to it I do like your last suggestion of using the IB15s for music and building a dedicated LFE sub for HT.

[JohnR]

If your electronics are up to it I do like your last suggestion of using the IB15s for music and building a dedicated LFE sub for HT.

And... it looks you already have nice baffles made for those already. Why not just stand them up in the room and measure them?

[RNRGAGNE]

I think I'd have to rip the wall down to get the baffles out because of the way they're built in.. 

When you say 300w per driver - would that be 600w per pair regardless of how they're wired?

[JohnR]

I thought you were going to have to rip them out anyway. But yes, the modeling was with 300W per driver. Really, I'm just suggesting that you spend a bit of time to learn how to do your own modeling for yourself

[RNRGAGNE]

Yeah the room would be quite different though if I had the front wall ripped out. I might build temporary baffles to try out just for fun. Maybe it was wishful thinking that I'd get an easy foolproof answer asking the questions I did! No such thing I guess lol!

[RNRGAGNE]

If you could humor me one more time, how much power should I use if I try a couple of OB's with two driver per side?

[RNRGAGNE]

A temporary box wouldn't be too tough to try either I suppose...

[JohnR]

You've totally lost me, I thought you were moving them to a different room anyway.

[RNRGAGNE]

Sorry my friend, if I've totally lost you imagine what it's like inside my head..

The room I'm going to build won't be too disimilar in the front lay-out from the one I have now so if I don't rip down the front wall I can test these units with the screen and speakers in position to give me a better feel for what results to expect in the new room to some degree. 

[gitarretyp]

I'd go for ~300W per driver in an OB.

What ThomasW said about not using this in a sealed enclosure is a little alarmist. No, these drivers don't have the thermal capacity of a driver designed to be used sealed, but I highly doubt you'll burn-up the coils using them in a large sealed enclosure. Keep in mind these drivers (or at least their 10 and 12" counterparts) are regularly used and recommended for use in auto applications, where IB means using the trunk as a large "sealed" box. If you want an authoritative opinion, pose the question on the AE forums, but I'm pretty confident they'd be fine in a large sealed box.

[RNRGAGNE]

Does the impedance I wire them at have any bearing on things or just on the amp load? (The ICE amps I have are stable down to 2ohms..)

[RNRGAGNE]

If you want an authoritative opinion, pose the question on the AE forums, but I'm pretty confident they'd be fine in a large sealed box.

Great idea!

[JohnR]

Does the impedance I wire them at have any bearing on things or just on the amp load? (The ICE amps I have are stable down to 2ohms..)

No, just on the amp. If the amps are happy with 2 ohms, then give it a try that way. Although I'm just wondering... don't you already have that sorted out with your current setup?

[RNRGAGNE]

I've had them for so long I don't remember how I arrived at the power when I set them up. I'm powering them at 250w @ 4ohms per pair.

[RNRGAGNE]

Quick update,
I buit a pair of temporary OB's with these drivers. They turned out really easy to EQ, ending up flat through their FR range according to Audyssey, and sounded really good with music, same as the IB in that respect, but running them in L/R mode they couldn't keep up in output with the mains when the volume increased. Running them summed made an appreciable improvement, but in the end they just don't get me where I want to be.
I'm going to put them in large boxes, 400L/pair x2 and see what that gets me.

[mcgsxr]

Output in OB is the main challenge - as you noted, good sound is not that hard to chase down at reasonable levels, but to hit the high spl, you would need a LOT of woofers!

I bet the sealed boxes do the trick for you - helps that you started with quality drivers!