Originally Posted by cessna1466u
So almost 9cubic feet per cabinet. That is a little bigger than the marty cubes I have. Not too bad, just have to find the right box style and port size. Again thank you for all the help. I now have something I can go to him with. I know he thinks he needs a folded horn design or the tuba design to be able to get louder sound from these but maybe some cubes with the right ports might work out better for him as far as storage and carrying them around.
The "right" box will have dimensions that are based on "truck pack dimensions". This is a standard.
Typically, trying to hit as many dimension in multiples of 90" is a good thing. The most common are 22.5", 45", and 33", also referred to as 1/4, 1/2, and 1/3 "truck pack".
Port size can be calculated easily, most of the software programs will do this. The port area is based on an acceptable level of air velocity, typically 2-3% of the speed of sound. For pro audio designs, I've always gone at least 20% larger in area, which of course increases length too. Port noise in a home design at a few watts is one thing, pro audio designs spend a lot more time riding the ragged edge of disaster at their power limits typically, and larger ports make for less port noise.
Also, Baltic Birch plywood is the standard for good pro audio loudspeaker builds. 18mm would be my first choice, but 15mm could be used if you design nice internal bracing to keep the cabinet walls stiff. Bracing also is very important for overall cabinet strength, important when they're being moved and set up/down for a living. A pretty lightweight design could be had in 15mm with these neo woofers. For larger cabinets like these, good square cuts with straight edges are essential. I'd really recommend having a shop(wood supplier or otherwise) with a panel saw at least make the first or second cuts on the plywood stock first if you don't have a good table saw. Dado the top and bottom pieces to take the sides and baffles, as well as the first couple of major braces. It adds strength, but more importantly, makes it easier to assemble. Use pnuematic staples or finishing nails to pin pieces together as you glue up the cabinet(every 4-5"), and if needed, the occasional screw.
My preferred finish is Line-X. Period. The DIY Duratex/Polane types are okay, but Line-X outshines them all in toughness.
These will want a dolly to roll them around, or casters attached on a cut corner(See JTR Orbit Shifter Pro for an example), and handles-nice big recessed handles. Dual Neutrik Speakon panel mount connectors are the usual standard input, mounted on a nice recessed plate for protection.
Nice handle: http://www.parts-express.com/steel-bar-speaker-cabinet-handle--262-821
Nice input plate/dish: http://www.parts-express.com/penn-elcom-d028k-dish-two-ep-nl4mr-black-5-x-7--262-335
The best caster and standard for pro audio gear dollies: http://www.greatlakescaster.com/colson_caster_corporation___swivel_caster___4_x_2_polyurethane_on_plastic_swivel_caster-4.04109.929.php
The 3.5" version with 1.25" wide wheel is acceptable too, but the larger diameters roll over cracks and stuff better.
Tee-nuts for driver mounting, either 10-32 or 1/4-20, depending on the speaker basket holes.
Foam tape to seal the driver against the baffle.
Good old 12 gauge hook up wire for connections, and use the .187" quick connects on the Speakons. UL type 1015 stranded hook up wire, get different colors for + and -, and if using multi conductor Speakons(4 or 8 pin versions), don't repeat colors.
On the cabinet design, set back the front baffle an 1" to 2". You will want some kind of metal grill, either the round "waffle" style over each driver, or a full metal grill cut to size. On a large cabinet like these, a full grill will need to have a seat on all four sides. Good source for cut to size perforated metal grills already finished in black powdercoat: