power vs cone area

Dragon_fire · Post by **Dragon_fire** » Fri May 20, 2005 1:45 pm

It has always been my understanding that larger cone area produced better results then more power. Is this correct ?
Im thinking along the lines of would (4) 10 inch subs given 200 watts each be louder then (2) 12 inch subs given 400 watts each ? given that the subs are the same sensitivity etc etc. im wonder this becuase im thinking of getting rid of my (2) JL 12w6v2's and replacing them with maybe (4) 10's of an undecided brand.

Jszar · Post by **Jszar** » Fri May 20, 2005 2:18 pm

you have the basic idea right. you'd have to double the amount of power to gain just a few decibles, where as adding a sub would give a gain of several depending on the situation.

Dragon_fire · Post by **Dragon_fire** » Fri May 20, 2005 4:11 pm

double the power rms to gain ~3dbs (Which is effectivly a double in "volume"). Alright, just making sure. Thanks for the reply

Post by **GlassWolf** » Fri May 20, 2005 4:22 pm

no.
double the power = +3dB
going from one sub to two = +3dB
double the audible volume is +6 to +10dB or four to ten times the power.

remember these are vague rules of thumb and a lot depends on the drivers themselves. if you reach peak excursion before you double the power for example, you won't get the same gain from double the power as you would from twice the number of subs. There are a lot of factors to consider so there's no cookie cutter answer to this that'd apply to all situations, or even most of them.

Dragon_fire · Post by **Dragon_fire** » Fri May 20, 2005 4:30 pm

bah, foiled agian.... grrr I hate this hobby some times.

audiobass10 · Post by **audiobass10** » Fri May 20, 2005 6:23 pm

A lot of times it really comes down to the box. That's somethin i've learned through various comparisons between setups. For instance my 15" Comp VR blows away 15 L7's sealed and even some in shitty ported boxes. Really take the time to learn what designs are good and what works in your vehicle. 4 10's can get hella loud if you know what you're doin. For that matter 4 of practically anything can get loud, but in most cases you'll have to sacrafice some major SQ. But honestly, what SQ buffs run 4 sub setups anyways.

Mithrandir · Post by **Mithrandir** » Fri May 20, 2005 7:48 pm

i believe a lot has to do with the box

71buickfreak · Post by **71buickfreak** » Sat May 21, 2005 4:39 am

here look at it like this. I recently did an SPL\SQ dual system for my buddy. I used a 2.5cube box, with a large spl port (tunes around 45hz, is 45square inches and 13.5" long) and a slide-in SQ port that is 15 square inches of port area and 15.5" long. this is for a single 12. in his 01 eclipse, running a single Crossfire 2000d at 4 ohms (Ineed to get it down to .9 ohm for SPL but it doesn't have the voltage where it needs to eb yet) and using the SQ port it hit 137 flat on the new dB drag meter. all we did was uncork it (used the large port) and it hits 142. no change in power settings, nothing. Compared to his last vehicle, which I built, that had 4 crossfire 15"s in a wall in 2 seperated enclosures ported, running 4 amps that system did a 150 on the Audio Control meter, which when compared to the new meter, plays 6-8 db higher. So, taking that into consideration, the 1 12" is louder than the 4 15"s. It all has to do with the box. the sub just needs to be able to handle the power and have enough excursion. I run a single 10 in a 1 cube box in my convertible and it is loud enough for any sq guy and would give most other set ups a run for its money. I haven't metered it yet, but its in the 138-140 range.

Mithrandir · Post by **Mithrandir** » Sat May 21, 2005 8:50 am

heh if you can explain to me how to hit 140 with 2 12 id be happy

71buickfreak · Post by **71buickfreak** » Sat May 21, 2005 9:50 am

what kind of car do you have?
The system in the eclipse has a single 12" crossfire XT212 sub, 1 Crossfire 2000d amp. currently we are suing a single 2 ga power wire, but we need to upgrade to 2\0 for better voltage during competitions. We are using a 2.5 cube box ported with a 45 sq" area slot port, 13.5" long. this setup in your car will yield similar results. The key for big SPL is to find your cars resonant freq and tune your box about 5 hz below that. this gives you a natural boost form the box and the car and when you play that freq, it will be friggin loud. I build dual-purpose boxes, where I have large main prot and then a slider which allows me to tune it down for SQ