I am looking into these for some buddies of mine that have a band. They really need to fill in the bottom end with some good bass. I purchased a pair of stage 4's from you years ago, and haven't been in the mood for new speakers since. They are awesome, and when my buddies were talking about a sub, you were the first guy I thought of. Here's my questions.

What material do you recommend the sub boxes be built out of?

Would a single 12 pi sub driven with 800 mono watts be better than 2- 3 pi subs driven with 400 watts each?

Is the bass from the 12 pi directional, like a typical horn is?

Is the heat exchanger required, and can it be added later?

Do you have people using 12's and 3's in bands now?

How much does the 12 wieght? It looks huge?

Thanks