Quadraphonic surround format

The quadraphonic surround format consists of four full-bandwidth channels, arranged as front left and right and rear left and right (left surround and right surround). It is an old format used for music delivery. Mike Oldfield’s “Tubular Bells” is probably the most popular release in this format.

LCRS surround format

LCRS stands for left, center, right, and surround channel. This is the original Dolby Pro Logic format. The surround channel (placed directly behind the listener) is a bandwidth-limited (the treble content is reduced) monophonic channel.

5.1 (ITU 775) surround format

5.1 (ITU 775) is used for a few surround standards. This is the most common of the surround formats, and is the one you are most likely to use. The 5.1 channels are left, center, right, left surround (left rear), right surround (right rear), and LFE.

6.1 (ES/EX) surround format

The 6.1 (ES/EX) format is used for Dolby Digital EX or DTS ES. The 6.1 channels are left, center, right, left surround, surround (rear center), right surround, and LFE.

7.1 (3/4.1) surround format

7.1 (3/4.1) uses the same speaker configuration as 5.1, but adds two additional side channels (left mid and right mid), placed directly to the left and right of the listening position. It is designed for a big cinema, in other words.

7.1 (SDDS—Sony Dynamic Digital Sound) surround format

7.1 (SDDS—Sony Dynamic Digital Sound) adds two additional speakers to 5.1 (left center and right center). As with the other 7.1 format, this is designed for use in a large cinema, equipped with Sony decoding and playback hardware.