TTG said:
It's the airspace difference probably. Explorers have a huge amount of airspace over pickups and little cars, so the bass tends to not be as aggressive as it would in a smaller confines.
I thknk it's more frequency-dependant. Trucks have a much smaller cabin, resulting in a higher resonance frequency. This means that the truck is gonna peak much higher than an SUV. In my Ranger it's set up for loooow bass (I still wanna go lower) with an amp about the output of the JBL mentioned above. It really slams, I hear the looooow notes, but the loooow notes just are not as pronounced as in my gf's car.
My gf's car is a Taurus with fold-down seats. The box is tuned higher (it's a leftover box from my Ranger), and it has a much smaller amp than the Ranger. It might not hit as hard, but due to the much lower vehicle resonance frequency, the looooow notes are acccentuated much more than in my Ranger. I really feel my innards shaking.
TTG said:
Your best bet to get more thump is going to be get a ported or bandpass enclosure, you'll feel it a lot more due to the air coming out of the box.
You kinda got it right. Ported boxes just tend to be more efficient than sealed boxes. Sealed boxes simply allow the output of the front wave of the cone to be introduced into the vehicle cabin. The rear wave kinda pressurizes/depressurizes the enclosure, resulting in the "acoustic suspension" that controls the cone.
Ported boxes allow some of the energy resonating from the rear wave of the cone to work in harmony with the energy resonating from the front wave fo the cone. If you did not have a box the bass would get cancelled out. The rear and front wave must not come into contact with each other. The ported box is tuned to a specific frequency. The port is not a hole in the box, but a mass of air contained within the port that resonates at the given frequency. As the output of the sub nears the tuning frequency (Fb), the air in the port starts to resonate more and more. Put a plastic bag in front of the port on any enclosure while the sub is playing. The air does not just move out. It resonates back and forth, as long as the frequencies closest to the Fb are being played by the sub.
The port length allows for the rear wave to be out of phase 180 degrees. This means that the front wave and the rear wave that comes out of the port are now in phase with each other. They will not cancel each other out (or at least not nearly as much as a freeair subwoofer). The port can be considered a freebie subwoofer in the enclosure. You need to be careful with port size. Smaller ports result in shorter ports, but you can get a whistling or popping sound at high outputs near the Fb. Larger ports result in much longer ports (making box designing more complicated), but the larger the port area the more output that can come from the port. However TOO LARGE of a port can be bad.
The kind of bandpass most people know about is the 4th order enclosure. This is where the sub is in a sealed box. The front wave plays into a ported chamber. Depending on how it's designed the enclosure can have a wide bandwith (or frequency response), or it can be super-peaky at a small bandwith and sound like a one-note fart-monster. The latter is becoming popular in SPL competitions.
For more information on box types, check out this very informative website:
http://www.diysubwoofers.org/
TTG said:
That being said my new 12" Alpine Type-R in a bandpass box it barely fits in hits very hard even while underpowered.
The 2005 Alpine Type R subs are really good drivers. My buddy kinda discovered them. I mean who would think a "Type-R" sub would be any good. He was testing subs and came across one. For the low price the thing got really loud and handled an arse-load more power than the 500 watt rating Alpine gave it. These bad boys excel in ported boxes. With ported boxes you can tune them to meet your needs. It sounds like you want a higher-tuned box to sound more like your buddy's pickup truck.
Box tuning goes like this. You usually get an even amount of output with varying tuning frequencies, provided the box size itself is the same. A lower tuned box would result in the output being spread across a much wider bandwidth. Lower frequencies would be much more accentuated. However, in a higher tuned box, the output is much more concentrated at the tuning frequencies. It sounds a lot louder to the ear. One benefit of a higher tuned box is you can give it a wide port area, and then later you can add a port plug to reduce the port area, giving you a lower tune. Once you tune lower it's muuuuch harder to re-tune it higher.
Honestly a single Type R would handle that amp, provided you know what you are doing with it. Otherwise you could just pick up a pair of subs, and it will still match well with that amp. If you needed enclosure design help let me know and I will see what I could do. To begin with I would need EXACT MEASUREMENTS. First of all give me the (1) maxiumum WxDxH that you can use. Second I would need the (2) maximum WxDxH that you would like to use up to, meaning what restrictions in WxDxH you would like to place on the box.
Tempe
