First, what kind of material is the box made out of...ask if it's MDF. (Medium Density Fiberboard) If it's just particle board don't buy it. It'll break up with all that SPL over time. You can tell the dif between the two, MDF wood is very fine, it's basically just glued together sawdust with extreme pressure and heat. Particle board on the other hand is grainy, you'll be able to pick out each small chip of wood. It should be at least 3/4" thick...this is a must!!!!!! Anything smaller, leave it, MDF or not...although it's highly unlikely to find MDF less than 3/4".
Second, run your 12w6's in a series/parallel combination for a 4 ohm load. jlaudio.com gives you a diagram how to do it, it's actually really simple. Basically there are 2 voice coils on the w6's, one set of pos/neg connections on each side of the speaker. On each speaker connect one + to a - on the other side of the speaker...do this on all three. Now you should have a + and a - open on both sides of the speaker. Now connect all three's speakers positives together in parallel and all the negatives the same and you'll have 2 wires at the end. The speakers are designed to be used this way, they have 2 leads on each + and -. Read them out with a meter and you'll get 4 ohms. (3.94 actually, close enough)
I run my 3 12w6's the same way with 1000 watts mono and end up with 156db!! (of course, I built my box with type B bracing and a double face with Tube Driver Amplifiers)
Don't forget to use damping inside the box. use a whole bag of polyfil...you can get it at any fabric store, costs about 3 bucks.
Christian
