Quote:
Originally Posted by huff442
Question for 2fast4thelaw. Your subwoofer enclosure design intrigues me. I'm not familiar with the boundary loaded concept in a car sub. Is this similar in design to the super high output PA systems? Regardless, how did you determine the volume of the chamber in front of the speaker? What about the size off the slot opening?
|
The design is heavily influenced by High Output PA speaker design. The driver is angled slightly to horn load it to disperse bass energy. I will give a little tutorial on Boundary loading and Transfer Function and how they relate.
First off everyone knows that a subwoofer placed in a corner increases its output. This is because it has more boundaries to bounce off from. The more boundaries you can create, the more bass energy can be generated. In my enclosure the sub fires directly into the floor of the vehicle and bass is forces through a small chamber with a large vent at the very rear of the car. In a since this is a bandpass enclosure but the front chamber is not calculated to produce a specific frequency.
Transfer Function is maximizing the length of your bass wave from the subwoofer to you. In my enclosure the bass wave hits the very back of the car and bounces off of the rear window which then reflects it to the windshield which then reflects back to you.
Also Matt (BigAudioFanat) pointed out something I didn’t even think of. The downfireing driver transmits energy through the floor of the car so you get a lot of tactile feel. I feel this sub more than I can hear it. It feels like its right under my seat.
Here is a good link to illustrate what I am talking about.
Measuring Transfer Function, Boundary Loading & Soundwaves