youve all heard of them. literally. people whose cars you can hear coming for miles. people who wake you and your family up in the middle of the night with that obnoxious rap music. SPL enthusiasts.
i myself was once one of that genre. my old chevy corsica in her prime could hit well over 150 decibels with my twin power acoustik fubr 10" subs, and 1600 watt amp. the sound system was so loud that when i competed, i had to stand outside the car while the subs were going as not to destroy what was left of my hearing. back then, i did SPL (sound pressure level) just to be annoying.
now, i do it more for the techie aspect of things.
i recently installed a 200 watt RMS Audiobahn 8" dual voice coil subwoofer, and a Legacy 600 watt max 2 channel amplifier for my camaro. in no way is it as impressive as the 150dB system of my old car, but this little sub has impressed me in its own right.
i toyed around with different wiring configurations and different box designs and such. not suprisingly, some configurations were better than others. and being the technogeek that i am, i questioned why. ohm's law helped me figure it out.
my subwoofer can be wired into either a 2 ohm or 8 ohm configuration. meaning that depending on which configuration i used, i would have either more or less power running through the subwoofer. i initially used the series (8 ohm) wiring configuration because it's what i have always used, it is the safest configuration, and should be compatible with almost any amplifier.
it was loud, but i wanted to see if i could get it louder, so i switched over to the parallel (2 ohm) wiring configuration, and the subwoofer tripled in volume.
i researched electrical impedance on the internet, and i found out that the lower the impedance (ohms), the less resistance is encountered (resistance is futile if less than one ohm). 2 ohms obviously offers less resistance than 8 ohms, therefore, more power is offered to the subwoofer, thus increasing output.
also, the type of enclosure (speaker box) influences the decibel output of the subwoofer. i chose and built a vented box because of its acoustic properties. vented enclosures offer better acoustical properties whereas sealed enclosures do not. internal volume of the enclosure plays an important role in the acoustics as well. if the enclosure is too big, it will produce a poor sound, and if it is too small, it will do the same and possibly damage the subwoofer.
so next time someone wakes you up at three in the morning by blasting some Mike Jones out of their trunk, dont hate; participate! electrical engineering and acoustics are fun!
all wiring diagrams are property of Rockford Fosgate and i used them without permission.
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