Bit of progress,
Boxes are built save for the baffles, I am just in the progress of adding some additional small bracing areas to the cabinets. Just things like reinforcement triangles joining panels together and hopefully slightly reducing the resonance of some of those panels, or at least pushing it higher.
I probably should have built these with 25mm MDF, I did my towers and rears with that wood and its most definitely far more inert and rigid as a whole with that wood, bit of a bummer, so I guess just making sure I do the best bracing I can for what I have...
I have decided I am going to save the $600 cost of veneer and finish these with Duratex. I admit its the easy way out and a little bit of a shame, but the reality is, I care very deeply about BLACK theatre and maximising contrast from my projector, so, just as I have black velvet covering all the veneer and thus, reflection on my current towers, with curtains on the opposite sides completely blocking any view of the veneer, I felt it was just going to be a waste of time since the first thing I would do is cover them with velvet again, furthermore, when I finally get to be able to build a proper screen wall and stick these beasts behind an AT screen, they will completely disappear. So duratex it is. I will save the single sheet of Jarrah I have for smaller projects where the beauty can actually be on show. This does however significantly speed up the time to finish and the ease of finish, now I can just sand the boxes totally smooth baffles attached and hit them with a spray gun.
LF Boxes... still adding more bracing to these, I think I might even add some lead or bitumen to the inside, and then some foam over that. Thoughts? They will only need to play up to about 350hz crossover, and the good thing is they will be structurally disconnected from the mid and tweeter box.
Ports are rounded over on the inside of the box, so they should have good airflow, I will also round-over the exit of the port.
Mid box, will add some more bracing triangles connecting the middle window to the sides and top/bottom in that exposed front section there. I think for these I definitely will add a whole lot of bitumen or some sort, dense foam, and then even some poly fill as these are going to be sealed, I want to do my best to subdue that rear wave. 350hz - 1200hz.
Tweeter Box. Same thing with the bracing triangles here, and the bitumen, foam and polyfill. One thing I sort of discovered, I may have made that window just a little small, when I was hitting the boxes with compressed air to get some dust off, when I hit that tweeter box, it resonated, I think I have inadvertently created a sort of massive internal port. I think what I may need to do is take a drill to the front bracing window there on the sides and open it up, add some smaller 2-3inch holes on either side for eg to just break up that effect. Perhaps 4 holes on the outer corners will do.
Any thoughts on where I may need to add some more bracing ?
You think adding some strips here would do anything (See the black lines)? Or do they really need to be hitting the very opposite panel? I guess I could do that, just insert it far enough into the box that the rear of the woofer wont interfere with it.
The red lines are things I am already doing... just haven't glued them yet.