Editing Subwoofer (section)

===Home audio===
The use of a subwoofer augments the bass capability of the main speakers, and allows them to be smaller without sacrificing low-frequency capability. A subwoofer does not necessarily provide superior bass performance in comparison to large conventional loudspeakers on ordinary music recordings due to the typical lack of very low frequency content on such sources. However, there are recordings with substantial low-frequency content that most conventional loudspeakers are ill-equipped to handle without the help of a subwoofer, especially at high playback levels, such as music for [[pipe organ]]s with 32' (9.75 meter) bass pipes (16 Hz), very large bass drums on symphony orchestra recordings and electronic music with extremely low [[synth bass]] parts, such as bass tests or bass songs.

Frequencies which are sufficiently low are not easily [[Sound localization|localized]] by humans, hence many stereo and multichannel audio systems feature only one subwoofer channel and a single subwoofer can be placed off-center without affecting the perceived sound stage, since the sound that it produces will be difficult to localize. The intention in a system with a subwoofer is often to use small main speakers (of which there are two for stereo and five or more for surround sound or movie tracks) and to hide the subwoofer elsewhere (e.g. behind furniture or under a table), or to augment an existing speaker to save it from having to handle woofer-destroying low frequencies at high levels. This effect is possible only if the subwoofer is restricted to quite low frequencies, usually taken to be, say, 100 Hz and below—still less localization is possible if restricted to even lower maximum frequencies. Higher upper limits for the subwoofer (e.g. 120 Hz) are much more easily localized, making a single subwoofer impractical. Home-cinema systems typically use one subwoofer cabinet (the "1" in [[5.1 surround sound]]). However, to "improve bass distribution in a room that has multiple seating locations, and prevent [[Null (physics)|nulls]] with weakened bass response, some home-cinema enthusiasts use 5.2- or 7.2- or 9.2-channel surround sound systems with two subwoofer cabinets in the same room.<ref name=HTSBG />

Some users add a subwoofer because high levels of low-frequency bass are desired, even beyond what is in the original recording, as in the case of [[house music]] enthusiasts. Thus, subwoofers may be part of a package that includes satellite speakers, may be purchased separately, or may be built into the same cabinet as a conventional speaker system. For instance, some floor-standing tower speakers include a subwoofer driver in the lower portion of the same cabinet. Physical separation of subwoofer and satellite speakers not only allows placement in an inconspicuous location, but since [[sub-bass]] frequencies are particularly sensitive to room location (due to room resonances and reverberation 'modes'), the best position for the subwoofer is not likely to be where the satellite speakers are located.

Higher end home-cinema systems and enthusiasts may also opt to take low-frequency bass reproduction even further by incorporating two or more external subwoofers.<ref name=DellaSala2009 /> Having two subwoofers placed around the room ensures even distribution of bass, reducing subwoofer localization and pressurizing the room with low frequency notes that can be felt, just like the cinemas.<ref name=ExpertsAgree />

For greatest efficiency and best coupling to the room's air volume, subwoofers can be placed in a corner of the room, far from large room openings, and closer to the listener. This is possible since low bass frequencies have a long [[wavelength]]; hence there is little difference between the information reaching a listener's left and right ears, and so they cannot be readily localized. All low-frequency information is sent to the subwoofer. However, unless the sound tracks have been carefully mixed for a single subwoofer channel, it is possible to have some cancellation of low frequencies if bass information in one channel's speaker is out of phase with another.

The physically separate subwoofer/satellite arrangement, with small satellite speakers and a large subwoofer cabinet that can be hidden behind furniture, has been popularized by multimedia speaker systems such as [[Bose Acoustimass Home Entertainment Systems]], [[Polk Audio]] RM2008 Series and [[Klipsch Audio Technologies]] ProMedia, among many others.<ref name=PolkAudio /><ref name=ProMediaUltra />

[[File:Subwoofer Genius 2.1 360(2).jpg|thumb|upright|A small subwoofer cabinet designed for use with a home computer]]

Low-cost HTIB systems advertise their integration and simplicity. Particularly among lower cost HTIB systems and with [[boombox]]es, however, the inclusion of a subwoofer may be little more than a marketing technique. It is unlikely that a small woofer in an inexpensively-built compact plastic cabinet will have better bass performance than well-designed conventional (and typically larger) speakers in a plywood or MDF cabinet. Mere use of the term "subwoofer" is no guarantee of good or extended bass performance. Many multimedia subwoofers might better be termed "mid-bass cabinets" (80 to 200 Hz), as they are too small to produce deep bass in the typical 20 to 100 Hz range.<ref name=AbsoluteBest />

Further, poorly-designed systems often leave everything below about 120 Hz (or even higher) to the subwoofer, meaning that the subwoofer handles frequencies which the ear can use for sound source localization, thus introducing an undesirable subwoofer "localization effect". This is usually due to poor crossover designs or choices (too high a crossover point or insufficient crossover slope) used in many computer and home-cinema systems; localization also comes from port noise<ref name=Garcia2017 /> and from typically large amounts of harmonic distortion in the subwoofer design.<ref name="subwooferSurSnd" /> Home subwoofers sold individually usually include [[Audio crossover|crossover]] circuitry to assist with the integration of the subwoofer into an existing system.