Mounting subs outside of box?

I've seen subs mounted outside of the box a lot lately.  I have 2 ten's with huge magnets and chrome/red-chrome baskets.  The back looks pretty sweet and I wouldnt mind showing them off.  Do the box specs stay the same when mounting this way??  Also does this help or hurt sound quality or does it stay about the same if you use the same size box?  And finally, I have heard that you need to wire the subs in reverse polarity if you mount them backwards.. is this correct? 

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Donnie

Some of the sub manufacturers now are including air space requirements in the manual for reverse-mounted subs.  What speakers do you have, and have you looked through the manual for that info?  When a sub is inverted, it is not taking up air space in the enclosure.  You have to account for that when you build.  Also, there is some area in the cone that is added to the enclosure air space, and that, too, has to be accounted for.

If you want to use the same box you have now, you can add solid filler at the cubic inches of the sub displacement.  Glue a piece of 2 X 4, or use a brick, to take up air space that the woofer is now (inverted) not occupying.  Find the displacement of the sub from the manufacturer, and measure the items you use to amount to the same cubic inches.  Cubic feet times 1728 equals cubic inches.

Wire your subs normally, according to the proper diagram.  You can reverse polarity at the amp terminals or use the 180 switch on the amp.  If you reverse at the sub, it gets confusing and can lead to double-reversing (which accomplishes nothing).  In fact, as long as the two subs are wired the same as each other, you can experiment at the amp terminal as far as reversing goes.  It's not always going to sound best with polarity reversed.  Try it both ways and use the way that gives you the most bass response.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

Just happen to come across this post and I have to say-That is probably the most and best information about inverted mounting that can be found on the internet.  people are wanting me to do it for them all the time, and i had to learn the hard way, trial and bust it up and try it again. stevdart, the world owes you a beer.  Keep up the good advice.

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If it don't fit, Force it.
If it breaks, You needed a new one anyway!

I have a pair of Volfenhag zx-4810 dvx subs.  I know a little about what all the specs mean, but I don't know if any of these is displacement or if I can figure it out with these.. here are the specs in the paperwork..

Fs- 27 Hz, Qts- 0.4448, Qes- 0.4745, Qms- 7.1149, Vas- 36 L, Sd- 0.0346m, Re- 3.2ohm, Nominal Impedance- dual 4ohm, Mounting depth- 152mm, mounting diameter- 235mm.   Can you tell me anything from that?

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Donnie

check out the link to the https://www.the12volt.com/caraudio/theile.asp  There you will find what all the little numbers mean, but I dont think the numbers you gave will help with driver displacement.  If not, look for one of equivalent size and shape that does give a figure for displacement.  Hope this helps.

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If it don't fit, Force it.
If it breaks, You needed a new one anyway!

If you can't get information from the sub manufacturer on the displacement or on the recommended box volume, then that is clearly an indication that this maker does not consider sound quality a priority.  In that case, it takes experimentation.

And thanks, tbirdman, for your comment above.  I would have to say that my post above has to do only with this situation, though, and is not a general purpose response to wiring inverted speakers.  This thread is a situation where all the speakers are inverted.

In a lot of cases, installs are done where there is a combination.  Some are mounted normally and some are inverted.  In these situations, the wiring that connects the speakers is reversed on the inverted subs as compared to the normally mounted subs. 

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

I just tried this for fun while I was re-building my trunk setup and it sounded great! Looked cool too. The 8000 mtx's I flipped have huge 102oz magnets that look really impressive. If I had space, I'd do a flipped enclosure with 2 Top-End Diamond Audio subs.

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BOOM, BOOM, BOOM BOOM....