Overview of surround formats in Logic Pro for Mac
Logic Pro for Mac supports 10 surround formats: Quadraphonic, LCRS (Pro Logic), 5.1 (ITU 775), 6.1 (ES/EX), 7.1, 7.1 (SDSS), 5.1.2, 5.1.4, 7.1.2, and 7.1.4.
The type and number of channels for each surround format is indicated by the numbers in its name. The first number indicates the number of main channels (ear-level speakers). The second number indicates the number of LFE channels (often, a subwoofer). The third number indicates the number of top channels (usually overhead speakers).
For example, a 5.1 surround system has five ear-level speakers and one LFE. Similarly, a 7.1.4 system has seven ear-level speakers, one LFE, and four overhead speakers.
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.
5.1.2 surround format
The 5.1.2 surround format starts with the same speaker configuration as 5.1 but adds two overhead side channels (left top mid and right top mid), placed left and right above the listening position. The 5.1.2 channels are left, center, right, left surround (left rear), right surround (right rear), left top mid, right top mid, and LFE.
5.1.4 surround format
The 5.1.4 surround format starts with the same speaker configuration as 5.1 but adds four overhead channels (left top, right top, left top surround, and right top surround), placed left and right, both in the front and rear above the listening position. The 5.1.4 channels are left, center, right, left surround (left rear), right surround (right rear), left top, right top, left top surround, right top surround, and LFE.
6.1 (ES/EX) surround format
The 6.1 (ES/EX) surround 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 surround format
The 7.1 format is designed for use in a cinema and home theater systems. The 7.1 channels are left, center, right, left mid, right mid, left surround (left rear), right surround (right rear), and LFE.
7.1 SDDS surround format
The 7.1 Sony Dynamic Digital Sound (SDDS) surround format starts with the same speaker configuration as 5.1 but adds two speakers (left center and right center). This is designed for use in a cinema equipped with Sony decoding and playback hardware. The 7.1 channels are left, center, right, left center, right center, left surround (left rear), right surround (right rear), and LFE.
7.1.2 surround format
The 7.1.2 surround format starts with the same configuration as 7.1, but adds two overhead channels (left top mid and right top mid), placed left and right above the listening position. The 7.1.2 channels are left, center, right, left mid, right mid, left surround (left rear), right surround (right rear), left top mid, right top mid, and LFE.
7.1.4 surround format
The 7.1.4 surround format starts with the same configuration as 7.1, but adds four overhead channels (left top, right top, left top surround, and right top surround), placed left and right, both in the front and rear above the listening position. The 7.1.4 channels are left, center, right, left mid, right mid, left surround (left rear), right surround (right rear), left top, right top, left top surround, right top surround, and LFE.
