Surround back speakers
The THX Surround EX format adds new “Surround Back” (SB) channels to the conventional
Change of positioning and acoustic image
with
FL | SW | C | FR |
SL ch |
|
| SR ch |
Change of positioning and acoustic image
with THX Surround EX system
FL | SW | C | FR |
SL ch |
|
| SR ch |
|
| SB ch |
|
Movement of acoustic image from SR to SL | Movement of acoustic image from SR to SB to SL |
Speaker(s) for one or two channels are required in order to achieve a THX Surround EX system with the
2Number of surround back speakers
With THX Surround EX, the surround back channel consists of one channel of playback signals, but we recommend using two speakers. When using dipolar speakers in particular, it is essential to use two speakers.
Using two speakers results in a smoother blend with the sound of the surround channels and better sound positioning of the surround back channel when listening from a position other than the center.
2Placement of the surround left and right channels when using surround back speakers
Using surround back speakers greatly improves the positioning of the sound at the rear. Because of this, the surround left and right channels play an important role in achieving a smooth transition of the acoustic image from the front to the back. As shown on the diagram above, in a movie theater the surround signals are also produced from diagonally in front of the listeners, creating an acoustic image as if the sound were floating in space.
To achieve these effects, we recommend placing the speakers for the surround left and right channels slightly more towards the front than with conventional surround systems. Doing so sometimes increases the surround effect when playing conventional
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