Should I move the woofer closer to the top edge of the cabinet, since there will be no tweeter on board? What change(s) do I need to make to the port given the change in woofer and cabinet volume? If I go 3/4 instead of 5/8, do I need to further adjust the port size, or just reduce the thickness at the port to 5/8?

Keep your ears and your mind open.

With each different model woofer, the box is tuned differently, appropriate for the motor's characteristics. If you use the Alpha 12, the box will need to be at least 5 cubic feet. So the cabinet size of the tower two would work pretty well, but the cabinet should be tuned a little lower. PiAlign recommends 5 cubic feet, which should be considered a minimum volume for that particular woofer. Other motors will have their own unique requirements for motor chamber, so it is best to match the woofer with an appropriate box. But it's pretty easy to do, and I think you'll be very pleased with your results.

The system you've described sounds nice, and if you need any of the parts, we have all of them in stock. We have everything available from the midwoofers and compression tweeters to the horn flares and crossovers. You might find it easiest to purchase a three π kit in the "π Speaker Kits" section rather than to order parts individually.

Nearly as soon as I posted, I realized a 2pi didn't make a lot of sense for where I was going.

I'm in what gets referred to around here as the"tube-friendly" camp, although I think a lot of us are actually in the SET-friendly camp, which is even more demanding and less forgiving than some of the PP tube amps. So power handling is not a consideration, but keeping the amp happy is. The less compensating I have to do in the xover, the better I like it, so flatter uncompensated response looks like a good thing.

I'm going to use Martinelli horns w/PSD2002's. I'm thinking that I should be able to cross them over somewhat lower than the smaller flare on the face of the spkr cab allows. Does this make sense?

Keep your ears and your mind open.

I'm sure you'll be very pleased with the midrange response of the Delta 15, so don't hesitate to crossover high.

G.

Actually the meeting's the 3rd. I goofed on the first announcement. I try to keep 'em on a Sunday.

10's! Yeah, now yer talkin'!

Keep your ears and your mind open.

And no matter what he says, the 10's are out of the question. (At least as long as I live on the 3rd floor!) ;-)

Thanks for all the info. Can't wait to build these babies!
Keep your ears and your mind open.