Bass Reflective

Bass-reflex enclosures improve the low-frequency response of loudspeaker systems. Bass-reflex enclosures are also called "vented-box design" or "ported-cabinet design". A bass-reflex enclosure includes a vent or port between the cabinet and the ambient environment. This type of design, as one may observe by looking at contemporary loudspeaker products, is still widely used today. Although the construction of bass-reflex enclosures is fairly simple, their design is not simple, and requires proper tuning. This reference focuses on the technical details of bass-reflex design.

 

  Ported

Ported Enclosure

Ported enclosures use a tuned port or vent to increase output at lower frequencies. Air inside the vent acts like a piston or motor that moves in the phase with the woofer reinforcing frequencies.

Pros: Increased efficiency, increased low frequency output, relatively low distortion.

Cons: Larger enclosures less tolerant of design/construction errors, no woofer control below tuning frequency.

Ported SPL

Ported (SPL)

Extremely large enclosures with very large port area. These enclosures have high ripple and are used to pinpoint and boost a specific frequency.

Pro’s: Very high SPL

Con’s: Very high f3 (woofer control is lost below f3), trying to reproduce musical frequencies will result in woofer failure.