Firing Subs down

Is it helpful when you have limited air volume inside the vehicle to fire the subwoofers down? For example, will it be more benifecial for me to fire 4 12's down rather than towards me or the back of the truck?

Casey

the only way that would accomplish using less air space was if you ment having the subs inverted on top of the enclosure. if thats what you ment then yes it will help with your airspace problem other wise no. also not all sub can effeciently be fired downwards as stated in many post lately 1 being here.

https://www.the12volt.com/installbay/forum_posts.asp?tid=30658&KW=down+firing

Another thing to consider is the opening or space between the subs/box and the floor. It you place the box to close to the floor, you can cause some issues with  cancellations and whatnot. I'm going thru this exact same thing with my setup (still working on).

According to JL Audio, the rule of thumb is the opening the subs fire out of must be at least 60% of the cone area of the woofer(s).

So be careful with how you set everything up, and you should be fine.

There needs to be "clearance" between the subs and the floor of your truck. This allows the subs to do their work (move back and forth) and produce sound. To get the box off of the floor, you will need to make spacer blocks around the perimeter of the box or just add so much extra stock to your box dimensions to get the box up. If you use the latter method, you will need to leave one (or more) sides open. This "opening" will need to be big enough to get the proper sound from your subs without wave cancellations occuring. See my previous post to determine the opening size.

In my case, I will be using 3 10" subs. Taking the surface area of (1) sub, multiplying X3, then multiplying again X.60, gave me an "opening" of 141.xx in^3. So my box needs to be like 3" from the floor with a width of nearly 47" across. Since I plan on using spacer blocks, I should be more than safe in getting the best sound from my system.

Hope this helps.