Box Building


All subwoofers are NOT created equally. Just because it is a 12 inch subwoofer does NOT mean it works in ANY 12 inch subwoofer enclosure!

It is beyond the scope of this tech tip to discuss all the virtues (pros and cons) of each.  We will keep the discussion to sealed versus vented
as these are the 2 most commonly used enclosures for car audio applications.

Remember there are 2 types of energy in car audio.  Electrical, which ISN’T free, and acoustical – which is FREE.  Typically no one complains to their retailer/installer that they got TOO MUCH BASS!  Everyone complains about not getting enough!!! So let’s FIX that!  Design and build better subwoofer enclosures.



SEALED: Advantages

1. Simple to build, no real thinking involved.Hard to screw up

2. Best phase and time response.


SEALED: Disadvantages

1. Loose typically 3 – 6dB of output versus vented

2. You’ll need 6dB more power to get to the same point in output as a vented enclosure. Or like going from a 500 watt amplifier to a 2,000 watt amplifier. And the subsequent additional current draw. 500 watts is about 58 amperes, versus 2,000 watts which is 233 amperes (full power current draw)



VENTED: Advantages

   1. Gain 3-6dB of output over sealed. Or
       roughly the equivalent of having a 500
       watt amp “act” like its 2,000 watts.
       Vented Enclosure is giving you FREE energy
   2. Better transient response.
   3. Less current draw because you can utilize 
       a smaller amplifier.

 VENTED: Disadvantages

   1. Much harder to design and build. Really
       need a modeling program to do that.
       We recommend WinISDPro. Which is
       FREE!    Go to this URL:         

   2. Typically about double the size of a
       sealed enclosure. But still relatively small
       in the scheme of things.
   3.  If you design the box incorrectly (in other
       words mistune it, for example tune below
       Fs of driver {highly discouraged}) it can
       damage the woofer