tjamz

DB Drive K710 D4 has been a great sub and is priced right, but even a DB Drive K510 D4 would work well I'd think. Heck, you might even want to look at a K3 10D4 if you are looking for a lower power higher efficient (at lower power) sub. It really comes down to your amp at that point. You could probably look at Atomic OEM series 10's (not on their site unfortunately)

Who have you spoken with at RE? Try calling in and asking for Greg Carolus (if you haven't already). PM me if you need his direct contact info.

Tips for an IB setup: Seal the trunk from the cabin, this sounds like a no-brainer but can be difficult to do properly. This means you need to seal the rear parcel shelf, the back seat, the pockets that go over the rear wheels, etc... If it can leak into the cabin, seal it. Also with an IB setup the trunk acts as your enclosure. So a smaller trunk is kind of like having a smaller sub box, but usually the differences will be minimal since the trunk is still likely to be quite a bit larger than the "optimal" sub box. If you are looking for an added element of control, you could always try and fashion your own Aperiodic Membrane in front of or behind the woofer. Basically this becomes a resistively leaky box that in theory will produce the snappy bass on higher sub frequencies yet still go deep on lower frequencies. In the early/mid 90's these were almost a must have for SQ competitors. A good subsonic is good to have, but again, subsonic filters have become a "standard" on amps only in the last decade or so (maybe late 90's) and cars still sounded great in IB setups before then as well. It's not like a vented enclosure where the sub loses all linearity below it's F3 point, in this case it is still a linear roll off of about 6 dB/octave since it is just a large sealed box.

Of those, I've had best luck w/ MS-8 (EASY to set up) and Bit Ten (More advanced)

Personally, I'd put in an MS8/BitOne/Bit Ten or similar processor REQ was alright in that it improved the bass arbitrarily, but it did not have anything to reference it against (no reference disc sent with for calibration it basically just adjusted the entire bottom 2 octaves by a given dB of gain). The ones listed above are 3 that I've personally used/seen used (I'm sure there are others that work as well or maybe even better) that will analyze all of your speakers to help you set up not just your subwoofers but also the time alignment and imagining for up to 4 seating locations while restoring the integrity of the sound as it was recorded instead of how some car manufacturer thought it should sound. It will also automatically tune your system for you to give you an extremely good starting point.

The scientific explanation applies quite well in an open field environment OR anechoic chamber so long as a driver is not being driven beyond it's capabilities. It's funny that you don't agree with the scientific theory, yet you come to the exact same conclusion. As for enclosures not being equal.... By all things being equal (same sub, same amp, same listening environment, etc...) I meant that if the single sub setup had a 1.5 cu ft vented enclosure tuned at 35 Hz then the dual sub setup would have another 1.5 cu ft vented enclosure tuned at 35 Hz as well.

Commonly accepted acoustic theory dictates that if all else is equal (same make/model/enclosure/vehicle/placement/etc) dictates that 2 12's on 500 watts (total) will always be louder than 1 12 on 500 watts. You know, unless my professors all lied to me

Let's figure this out the old fashioned way (by using acoustical theory) Let's say that hypothetically a single 12" sub will get to 130 dB @ 250 Watts (this is what we are basing the rest of my example off of) If we double the power the amount of subwoofers we will pick up 3 dB according to accepted theory and arrive at 133 dB Alternately we could double the number of subwoofers (still remaining at 250 watts TOTAL) and gain 3 dB as well and also arrive at 133 dB If we double the amount of speakers (to two 12" subs) AND double the amount of total power (250 watts each/500 watts total) we will gain 6dB and arrive at 136 dB I conclude that 2 12" subs each receiving 250 watts (500 watts total between the pair) will in fact be louder than the exact same single subwoofer receiving 500 watts of power.

If the JBL MS-8 counts, then yes, I use that to restore frequencies off of stock head units (or even aftermarket ones)