Pi is a funny thing…

Back in the day when I was 16 and got my first car I was extremely pumped to get a stereo system in my car. I didn’t have a ton of money but wanted… No I HAD to get a system. I started with a Jensen A220 2 channel amp and some 6x9’s for the rear dash. I had state of the art flip down Sony ES cassette player that had preouts for the amplifier. I hooked the amp up to the 6x9’s and let those babies sing. It was awesome. At least it was awesome for a week until my buddy for some Rockford “by one get one free” Series 1 8” subwoofers. They were 99 bucks for the pair! He had the same Jensen amp I did and we built the box out of MDF in wood shop at school. It bumped and I had to get something bigger and better. My uncle worked at a car audio shop called Auto Tech at the time. 

He hooked me up with a pair of 10” Rockford “Punch” subs in a box with a Plexiglas face, spackle painted inside and a light that flashed with the bass. It was the coolest thing ever and it was way louder than my 6x9’s and my buddies Series 1’s.  I was still using the Jensen amp and was pretty happy. This is what got me into the car audio industry and now have spent a lifetime in it in some way. The good old days…

Once I started selling and installing car stereo I was trained on what you could do to make a system louder and sound better. All of the manufacturers had training times set aside for us each year and we got to learn all about the gear they offered and why one brand was better than another. I learned a ton and one of the best lessons was how to get more volume and that is what I’d like to share with you.

There are only a few ways to get more SPL from a system. Here they are…

Sound Damping

This is a great way to get more out of the system you already have. It’s also the least expensive way to get more SPL. By eliminating the sounds outside the car from coming inside the car you hear more of the speakers and less of the road noise. This helps you hear more of the bass and less noise. It didn’t really add more SPL though but tricked your ears into hearing more of it. By the way this is also great for sound quality and dynamic range!

More Power!

You would think that by doubling your power you would double your sound. Unfortunately it doesn’t even come close. There is a little rule we have that goes like this. Doubling your power merely increases SPL by 3DB. This is the least volume difference a person can hear. So all you did was turn the dial up 1. Yep. Depressing isn’t it. A good amp is important and goes a long way but don’t expect to blow your windshield off just because you added more power.

Increase Cone Area

This is by far the best way to get more bass. By increasing the surface area you are able to push more air back and forth creating more sound!  The percentage increase is not exact because it depends on what you started with but it’s a lot more than 3db when you double cone area. A LOT MORE!  Just don’t think that by going from 1 12” sub to 2 8” subs you are effectively getting a 16” subwoofer worth of performance. Nope. 2 8’s have about 12 square inches in surface area less than 1 12” does. Pi is a funny thing. To calculate surface volume of a woofer use: Area of a circle = πr2


There a few other techniques we can use to increase SPL like rebuilding a better box or stuffing it with poly or glassing the inside etc… The best way to get more SPL is to get more woofer area. Then do sound damping and finally get a big nasty amp. If you’re like me you’ll never stop making your system better. Just wait until you want to get the best sound quality possible. It’s fun but requires a lot of time and good gear.

Have fun and turn down those bumps 6 blocks before you get home. Your Minneapolis neighbors will appreciate your neighborhood car audio more when they do not hear it..

If you are looking for more help, more woofer area, more power or some sound damping products come down to our shop and show us what you have. We would be more than happy to show what’s possible and get you hooked on a nice system for your vehicle. We have certified technicians and perform professional installation. We offer many brands of car amplifiers, car subwoofers, and products to connect your smart phone to your car audio system.