Editing Subwoofer (section)

===Enclosure designs===
[[File:Bandpass enclosure.png|thumb|Compound or 4th-order band-pass enclosure]]

Front-loaded subwoofers have one or more subwoofer speakers in a cabinet, typically with a grille to protect the speakers. In practice, many front-loaded subwoofer cabinets have a vent or port in the speaker cabinet, thus creating a [[bass reflex]] enclosure. Even though a bass reflex port or vent creates some additional phase delay, it adds SPL, which is often a key factor in PA and sound reinforcement system applications. As such, non-vented front-firing subwoofer cabinets are rare in pro audio applications.

Horn-loaded subwoofers have a subwoofer speaker that has a pathway following the loudspeaker. To save space, the pathway is often folded, so that the folded pathway will fit into a box-style cabinet. Cerwin-Vega states that its folded horn subwoofer cabinets, "...on average, produce 6{{nbsp}}dB more output at 1 watt than a dual 18[-inch] vented box" giving "four times the output with half the number of drivers".<ref name="CerwinVegaUnderstanding" /> The Cerwin-Vega JE-36C has a five feet long folded horn chamber length in the wooden cabinet.<ref name="CerwinVegaUnderstanding" />

Manifold subwoofers have two or more subwoofer speakers that feed the throat of a single horn. This increases SPL for the subwoofer, at the cost of increased distortion. EV has a manifold speaker cabinet in which four drivers are mounted as close together as practical. This is a different design than the "multiple drivers in one throat" approach. An unusual example of manifold subwoofer design is the [[Thomas Mundorf]] (TM) approach of having four subwoofers facing each other and sitting close together, which is used for [[theater in the round]] shows, where the audience surrounds the performers in a big circle (e.g. [[Metallica]] has used this in some concerts). The TM approach produces an omnidirectional bass sound.<ref name=McCarthy2016 /> Cerwin-Vega defines a manifold enclosure as one in which "...the driver faces into a tuned ported cavity. You hear sound directly from the back of the driver in addition to the sound that emanates out of the port. This type of enclosure design extends the frequency capability of the driver lower than it would reproduce by itself."<ref name="CerwinVegaUnderstanding" />

[[Bandpass]] subwoofers have a sealed cabinet within another cabinet, with the "outer" cabinet typically having a vent or port.