Surround sound effects in movies, music, and games are most noticeable with direct speakers.
In general, most people prefer direct speakers if they listen primarily to multichannel music.
The speakers that most people have in a basic stereo setup are typically direct-radiating speakers.
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If used as side-surround speakers, the sound is output both toward the front and rear of the room.
If used as rear-surround speakers, they output sound in both directions along the rear wall.
The dual speakers used in a bipole speaker are in phase, meaning that both speakers output sound simultaneously.
Bipole speakers create a diffuse surround effect, so the location of the speaker cannot be pinpointed.
Bipole speakers are a good choice for movies and music and are usually placed on the side walls.
In a large room, bipole speakers and direct-radiating speakers both work well.
If you prefer directional sound from the back of the room, bipole speakers deliver from that area.
The purpose is to create a diffuse and enveloping surround sound effect.
Dipole surround speakers are usually preferred by movie enthusiasts and are positioned on the side walls.