The classification of speakers has different viewpoints and specifications. According to the acoustic structure of speakers, there are closed boxes, inversion boxes (also known as low-frequency reflection boxes), passive radiator speakers, and transmission line speakers. See the relevant Q&A for their respective characteristics. Phase inversion box is the mainstream of the current market; Judging from the size and placement method of the speakers, there are floor boxes and bookcase boxes. The former is relatively large, usually placed directly on the ground, and sometimes foot nails for shock absorption are installed under the speakers.

Because the floor box has a large volume and is easy to use larger and more low-noise units, its low frequency is generally good, and its output sound pressure level is high and its power carrying capacity is strong, so it is suitable for use in occasions with large listening area or more comprehensive requirements. The bookcase is small in size and generally placed on the foot stand. It is characterized by its flexible placement and does not take up space. However, its low frequency is generally lower than that of the floor box due to the constraints of the box volume and the caliber and number of low-noise units.

The carrying power and output sound pressure level are also smaller, which is suitable for use in smaller listening environments; According to the bandwidth of the playback, there are broadband speakers and narrowband speakers. The planning policy of most speakers is to cover as wide a band as possible, which belongs to broadband speakers. The most common narrowband speaker is the ultra-low sound box (low sound gun) that is bulging with the home theater. It is only used to restore a band from ultra-low frequency to very narrow low frequency.

According to whether there is a built-in power amplifier or not, it can be divided into passive speakers and active speakers. The former has no built-in power amplifier while the latter has one. Now most household speakers are passive, but the ultra-low sound box is generally active.