Hi Ricci I'm just finished work.

Some more info. The power input for the smaller box is 500 watts for max SPL plot. The max SPL plot for the larger box is 300 watts.

Most important is this fact. These are simulations! Although I greatly respect this program in it's ability to model things accurately it does so using the real world converted to mathematical formulas. I posted most of the graphs into 1 Pi because that is the best I ever get loading a horn into a corner which mathematically is .5 Pi. In real life expect about 3 to 4 db less efficiency. So more or less 98 to 100 db/watt loading these horns into a corner.

I greatly respect the work of Tom Danley. His Lab horn is a tour de force in heavy duty low end horn design. But he designed it for exactly what you have described. Production sound. No one in a home is going to push their subs to the same limits of continuous SPL that you find in the Pro sound world. We are dealing with loud and very loud transients. That is the second reason why one well designed driver can get away with what is simulated. We at home will never on a continuous basis be pushing a horn as hard as in a Pro environment. How many times at a concert or medium sized venue can you actually get proper corner loading? The difference as you know is 6 db in gained reflection. That four times the power. So I design a little on the edge knowing that a bit more performance can be squeezed out at the risk of driver longevity considering no one will really be pushing the horn so hard that driver longevity would be an issue. Almost everyone that has a horn loaded sub at home mounts it in the corner. It is the optimum location and this horn is designed for the optimum location. Not in the open or like the LAB horn to be used in stacks of three or more.

One more point. I have been working designing and building horns since 1995. Not a really long time but long enough to have learned a thing or two. First and foremost that simulations are just that. Close approximations.

As an example I followed a novel box design simulation that started as a what if kind of idea. A little down the design path I posted the results in the Unhorn proof of concept thread. It is to short to produce the low end output that it showed when simulated. That is until you take into account the tapping effect that the driver placement creates. It effectively doubles the length of the enclosure . The pinch point creates not a horn load but a sort of bandpass enclosure effect. It is neither a true horn nor a true bandpass box but a hybrid. It simulated well and measured well albeit with the drop in efficiency of about 3 to 4 db between the simulation and the measurements that I have always come to find when translating a simulation into real life. Squeezing that last bit out from a real world design is an evil task I wish on no one.

So much of creating a horn lies from the point of modeling to the creation of the actual horn. There is a real art to folding these beasts. And it is none to easy. I have been a cabinet maker for some 20 odd years. Not making kitchens but stuff furniture and fancy mill-work. And I have to admit to this that the Dual TRIO8 Unhorn took me three folds and almost a week of consternation. What Tom and other gents have presented is really good engineering. What I'm putting up here is an attempt at good engineering. The proof will be in the pudding.

This thread is a poll as to what some gents knowledgeable or just plain interested would think of either type of enclosure.

Below I simulated the two drivers ( Lab12 and TRIO12 ) in the smaller horn. At 1 watt and at 100 watts. Remember that this horn is designed for the TRIO12 and that is very important. The motors on the two drivers are very different in some respects as you shall see. One of the reasons why I chose 100 watts is because that is where the LAB12 runs out of excursion. The TRIO12 is just getting up to almost 1/2 speed at 100 watts. So taking this crude comparison two LAB12's would keep up with one TRIO12 in this horn. It would also allow a bit shorter horn path. But the overall volume would only go down slightly as the rear reactance annulling chamber would have to be larger with the two LAB12 drivers. The SPL would potentially go up by 3 db or double the power. But unfortunately 3 db is where normal untrained listeners just begin to hear a difference in SPL. So I'm not so sure it is worth it.

Mark