Subwoofer enclosure or IB sub speaker ring mount to wall:
@Addicted had asked me a question regarding my sub placement and this setup. He mentioned that I did not talk about how to install my enclosure in this thread. I haven't finished the install yet, so I had not posted anything on it yet. Until I do, here is how I intend to install the enclosure.
With either an IB (infinite baffle or free air) or an acoustic suspension enclosed sub, optimum placement would be the same. Getting 100% of the grille area into the listening environment will get 100% of the sub involved in musical reproductive support. Anything short of that is well, short of that. So choosing to to with a sealed enclosure vs IB would be a waste of time and money if I didn't achieve at least that. I won't get into ported designs as they just fall short of this as well. The mounting to follow gets 100% of what a 10" JL marine sub can deliver. The only way to get more bass is to have greater driver surface area (bigger sub or more of them), and/or more power behind the sub(s). Consider that putting a sound system in an open air boat is already a compromise of sorts, but life is full of compromise.
My mount will be the same as my IB install was in the Nauti Dawg, with the wall of the compartment sandwiched between the speaker itself, and either the birch speaker ring (IB sub), or the sealed enclosure (AS sub). In the Dawg, it was a speaker ring that the sub was secured to, not the wall. In the Blue Yonder, it will be the enclosure that the sub is secured to, not the wall. The enclosure with hole cut for the sub will sit flush against the interior wall of the compartment. It will be braced and supported from underneath to let it sit flush. The angles are not square, and the wall surface is fiberglass and not smooth. So I have used a grinder to just take the surface down a tad and will seal the box to the wall using silicone between them. Two screws will hold the box to the wall and in place, until the speaker is installed to actually sandwich the wall. The key is that nothing in this speaker mount is connected to the wall. Because the tremendous excursion of that driver will flex and crack a fiberglass wall easily if it is expected to carry the load placed on it. In other words, it can't carry that load long term. So you mount this speaker so that the wall is not part of the connection, and is merely sandwiched between the box and the speaker. I have said that now about 4 times in this post alone, because it is often missed and important to understand that having mounting screws that bite into the wall will chip/crack/splinter/spider and cause visible cracks in the wall eventually...and worse, it will counteract the travel of the speaker and you will lose performance from it. So mounting it where that won't happen is important. The way to do that, is to oversize all of the speaker mounting holes through the wall. So that the speaker mounting screw passes through the holes, and does not hold to the wall. The screw will hold to the box, not the wall. This requires test fitting and brings to mind, the chicken and the egg theory. Once the box is mounted and secured, you can't get behind it, but you need to align, drill, and check all of this. So set and drill your wall for the speaker mounting holes and make sure they don't hold and can be pulled out from the wall first. And very important...make sure you countersink and deburr all the edges of any hole through fiberglass to prevent it from chipping and spider cracking. Now that you know the mounting screws go through the wall and don't bite in it, you can silicone and secure the box for mounting. The speaker will mount to the box, through the wall, without the teeth of the screws pulling on the wall and cracking it.
I will take pics of the sub going in as I do it but I hope this helps some of you that have inquired how I was going to mount this box in the compartment.
