Could I just cut bigger holes top and bottom and skip doing cutouts on the backs?
I would prefer to keep it it pretty much as is. Making bigger slots in the top and bottom might weaken them too much, and there's quite a bit of stress on the top panel from the mounting system-that-shall-not-be-named!
I want it to stay square, plumb and rigid with all the tension on there, without bowing or twisting.
Also, the cutouts in the back panel serve an acoustic purpose too: I don't want resonances going on inside the enclosure box, and those help to reduce the possibility of that. The size and location of those cutouts is not too critical, so you don't need to cut them with high precision, but I'd still like to keep them there, more or less like they are. In the original design, before you decided to remove the amps, they also had an additional purpose: cable access. You would have run your power and signal cables through those cutouts, and you also would have used them to get at the controls on the rear panel, without needing to remove the speaker from the enclosure. Those two are moot now, as you won't have the amps in there, some from that point of view you don't need them, but from the other points of view, I'd leave them in pace, roughly how they are.
- Stuart -
Correct. Unfortunately. Plywood is way to dense and rigid, compared to Homasote. Plywood is around twice as dense, and more rigid. We could substitute the insulation, if we really had to, but not the core.