Custom 12" L7 Box Questions

[Dan and Christy]

I am looking to relocate my 12" L7 from the rear storage compartment(off the port quarter if you want to get fancy) to the middle compartment(abeam to port I believe). I have a beautiful custom sub box now that just will not fit into the new location. I would like to keep the new box as low profile as possible, long and wide as opposed to tall and boxy. So, I guess there are a few specific questions;

1. How low and wide can I make the box?
2. Should I maintain the sub in the down-firing position?
3. Should I maintain the sub in a ported box?
4. If I build a ported box, does the location/position of the port make a difference?

I am open to all suggestions and really appreciate the help.

[G-MONEY]

I am looking to relocate my 12" L7 from the rear storage compartment(off the port quarter if you want to get fancy) to the middle compartment(abeam to port I believe). I have a beautiful custom sub box now that just will not fit into the new location. I would like to keep the new box as low profile as possible, long and wide as opposed to tall and boxy. So, I guess there are a few specific questions;

1. How low and wide can I make the box?
2. Should I maintain the sub in the down-firing position?
3. Should I maintain the sub in a ported box?
4. If I build a ported box, does the location/position of the port make a difference?

I am open to all suggestions and really appreciate the help.

The only thing I question is.... In that location will it muffle the sound not letting the sound out?

[Dan and Christy]

The only thing I question is.... In that location will it muffle the sound not letting the sound out?

Would running the port to the walk through wall help that at all?

[chpthril]

I was just reading an older thread about custom boxes that Phil had posted some great info, as usual, and now I cant find it From a non-technical standpoint, the shape is not as important as hitting the suggested net volume. Phil had also suggested to CP3, the he needed to vent the compartment to let the sound out, it made a huge difference in level and quality when he opens the storage door.

[lee]

Why not mount it in the bulkhead under the drivers helm with a box on the back side?

[Dan and Christy]

Why not mount it in the bulkhead under the drivers helm with a box on the back side?

I already have a 12" MTX rocking there

[chpthril]

I already have a 12" MTX rocking there

Which MTX? Have you though about putting the L7 in it's place!

[Dan and Christy]

Which MTX? Have you though about putting the L7 in it's place!

I would like to keep both if possible I appreciate good bass

[Dan and Christy]

I'll have to check which MTX it is, but for some reason I think it is a Thunder 7000 or 9000 maybe?

[chpthril]

I would like to keep both if possible I appreciate good bass

Just kinda thinking, with the 750W RMS L7, the MTX might be like blue on black..........with the L7 in the right place and dialed in, you'll never miss the MTX (especially if it's the 200W Marine MTX)

[chpthril]

I'll have to check which MTX it is, but for some reason I think it is a Thunder 7000 or 9000 maybe?

Yeah, if it's a Thunder series, that's a serious sub

[philwsailz]

I am looking to relocate my 12" L7 from the rear storage compartment(off the port quarter if you want to get fancy) to the middle compartment(abeam to port I believe). I have a beautiful custom sub box now that just will not fit into the new location. I would like to keep the new box as low profile as possible, long and wide as opposed to tall and boxy. So, I guess there are a few specific questions;

1. How low and wide can I make the box?
2. Should I maintain the sub in the down-firing position?
3. Should I maintain the sub in a ported box?
4. If I build a ported box, does the location/position of the port make a difference?

I am open to all suggestions and really appreciate the help.

Hey you all, so sorry to be late to the party....

1. The key is total volume. Measure height, width and depth, and multiply them together. that will give you the gross external volume, (easier to measure). Make the new box fit, but make it so that the gross external volume is the same.

2. Down-firing usually provides some acoustic benefit, due to boundary loading. It also protects the woofer; more important in my opinion.

3. Ported will be the loudest, so yes. If you have a port tube in your current box, try to re-shape the new box, (question 1) so that the existing port can be installed. It will work the same if you can do this. If it is a slot port, you have to handle it a little differently, but I can help there.

4. Port location usually makes little difference. In rare cases it does, but this is really rare...


As for installing it in your compartment and accidentally containing the sound, the best thing to do is to find a good location to cut a large hole or two to let the sound out. I am thinking a 5" hole or two... Cosmetically you can make a little disk of ABS plastic, or something like that, cover it with window screen cloth, or even black double knit polyester. Then use some spare speaker grils, (try your local car stereo shop; they usually have hundereds laing around) to cover the little disk(s). That is just one option... They key is to get it hammering with the hole, and then do something to dress up the hole so it is not fugly...

Hopefully that all makes sense; if not post a reply here, (so other can see what you are doing) or PM me.

Good luck!

Phil

[Dan and Christy]

Thanks Phil, I was wondering where you were yesterday.

A quick question, you mention possibly cutting two holes in the walk through wall to let the sound escape from the closed hatch to the boat, do I route the port via some sort of flex hose to the holes or am I reading this completely wrong? Thanks guys, again I appreciate the help.

[Dan and Christy]

Another question, I can't seem to find a consensus on the size of a ported box for the L7. Any suggestions?

And yet another, I think I am starving the L7 for power, any good suggestions on an amp? I believe it is 750 RMS.

I am getting ready for the winter projects and want to get my crap in line before diving in and tearing stuff apart.

[philwsailz]

Thanks Phil, I was wondering where you were yesterday.

A quick question, you mention possibly cutting two holes in the walk through wall to let the sound escape from the closed hatch to the boat, do I route the port via some sort of flex hose to the holes or am I reading this completely wrong? Thanks guys, again I appreciate the help.

Reading it wrong sort of...

You want the sound output from the port and the woofer combined, not just the sound from the port. Simple holes with no tubing will allow the combined output of the woofer and the port to be heard.

If you go and add tubing to connect the enclosure port to the holes, you will change the tuning of the enclosure; not something you want to do. The results are unpredictable, and are usually worse.

So, just cut the holes, (or hole of any other design you think is cool and works for you) dress them up somehow without restricting sound/air flow and let that suffice.

Cool?