tullamore wrote:I think 10s will generally be tighter than 12s and, more importantly, as your 'ear' develops over time, you'll find yourself increasingly picky about quality. Is it possible to put a whole bunch of 8 inch speakers in series? What do you think that will do?
Hey Henry
Generally a 10 will play tighter than a 12 of the same model woofer, by virtue of less moving mass making it easier to control. However, there are many 12's that play tighter than 10's, and many 10's that play lower than 12's of other types.
The human range of hearing is usually about 20Hz-20kHz, so we want to generate this as realistically as possible in our sound environment. In order to achieve low bass like 20Hz, you need a speaker that is capable of playing deep frequencies. Sometimes achieving this means giving up upper bass tightness, because a looser long-throwing woofer is often more difficult to control at higher frequencies.
An ideal audio setup would have two sources... left and right... because we have two ears. Headphones are generally as close to ideal as we can get (though they have size limitations which often limit their acoustical bandwidth). In the home, we can have two speakers with equal path lengths (the distance from the speaker to your ears), which play full range as well. In a car this is much more complicated, as you are sitting off to the side, and you don't have a lot of room.
This is where you start playing with the acoustics of the car. To your advantage, a car has what's called "cabin gain", which is a phenomenon that occurs when the long bass waves reflect inside of the vehicle, offering a ~12 decibel/octave boost starting at approximately 60-80Hz or so. Because of this, if your woofer naturally rolls off at 12dB/oct at the cabin frequency, the gain will act to neutralize this, and you will end up having much more low bass than you would get in a home or open air situation.
To your disadvantage, you have stuff like phasing, time alignment, reflections and other acoustical issues to contend with. These effects can be challenged by using installation techniques, like sound deadener, EQing and DSP, which is all part of the fun and magic of car audio.
To contend with space, we also use acoustics to our advantage. The human ear is not good at locating deep bass frequencies, circa below 60Hz. Because of this, most of the best setups end up having some very capable midbass drivers up front, which take care of the upper bass region. Then you can get a deep playing subwoofer to handle only the lowest notes, and the effect is that, when properly phased, it sounds like this subwoofer is playing out of the front speakers.
So to relate this back to the main topic... I ran the RSD 10" for quite awhile, then switched to a pair of RSD 12's. The 12's would tear the car apart, but were obviously strained to play tight off of my meager 350 watts (when they could easily handle 1000). After putting the 10 back in for snowboarding season, part of me misses the ridiculous bass, but this 10" blends so much better with my front stage.
This is currently because I do not have the best up front midbass, nor do I have the processing it takes to properly phase subwoofers. My crossover frequency is around 90Hz or so, which means that the 12's were getting rather boomy and positional when pushed to the limits of my amplifier. The 10 on the other hand stays quite efficient in this range, and is much harder to locate... but I don't get the hilarious car shaking effects.
I will also be trying a single RSD competition 12 in a short amount of time, followed by a JL 8W7 woofer. With the 8W7, I am likely going to install it in a ported enclosure instead of my usual sealed, in order to make up for some output lost due to the smaller cone area, and boost the bottom octaves a bit. I am hoping this will give me the super tightness and boom that I want. If not, we'll just have to keep trying until I get it right. This is one of the unfortunate circumstances of my diverse musical tastes. If I just listened to rap, I would want a low playing loud woofer. If I just listened to metal, I would want a fast high playing woofer. Unfortunately I like both, and then some, so there's always going to be room for improvement.
An array of 8" drivers is an interesting but expensive prospect. If you can find an 8" woofer that can play flat down to 20Hz with cabin gain, while running it in an an array off of a reasonable amount of power, you could have a very nice setup.