Difference between HD15 & HD215

As an HD215 is two HD15 cabinets in a single cab, the frequency response will go very slightly lower and you should get an extra 3dB provided you have the extra power. And yes, the HD15 would be easier to transport.

A single HD15 is an awkward heavy cube with a PD154. Build HD215s, put a wheelbarrow style handle and castor set in them, and thank me later.

Risc_Terilia wrote: I've always thought of an HD as a pretty light box.

Thats what i thought, its just a cube with 2 main panels and 2 small panels with a driver, it doesnt get much lighter than that for a bass cab does it?

I would go for the 215, less trips to the van with a slight increase in weight, a 215 is big enough to put wheels on which IMO is much better than lifting and carrying boxes around!

not much point in changing the xover freq, especially if you runing them above scoops, the extra low end you get from the HD215 will be covered by the scoops anyway. Leave the crossover as it is, but you dont want to be running your drivers down to 0hz do you?

there's not much point building loading and running a set of cabs to cover 20hz of mid bass is there?

Run the HDs up to 160 like they are supposed to, let your mid tops do the rest, nothing will be strained unless you push it and the system will sound fine. if you want slightly more kick once the system is built, use your EQ to add it in.

They will not generate a "harder kick", they will just handle more watts within a smaller freq range

Risc_Terilia wrote: I've always thought of an HD as a pretty light box.

It's not the weight, it's the distribution of it and the opportunities for handle placement plus lack of castors. You end up hand balling a lot more than you really need to, and there's almost no benefits over doubles because you wouldn't really ever use them in singles.