Classe Audio SSP-600 owner manual Multichannel formats, Post-processing possibilities

multichannel formats

post-processing possibilities

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By contrast, modern soundtracks use discrete channels of information. That is, each speaker has a distinct signal that is completely independent of every other channel. This approach is clearly more desirable, since it gives the movie makers more creative control over the quality of your experience. Musicians also prefer discrete formats, since it allows them to place their instruments and voices with greater precision, to create the musical effects they desire.

There is a host of various multichannel formats available. Here is a summary grid to help you sort out the possibilities.

Name	# Chs	Discrete?	Notes
analog stereo	2	yes	as found on almost all sources,
			including tape decks & CD players
multichannel in	6-8	yes	a multichannel analog input used
			mostly for SACD & DVD-Audio
Dolby Surround	4	matrix	the original matrix decoding system
Pro Logic			designed to squeeze four channels
			into two and then retrieve them
Dolby Digital	1.0-5.1	yes	the most common modern digital
(AC-3)			source, used in HDTV, DVD, etc.
Dolby Digital EX	6.1	mostly yes	the center rear channel is a matrixed
			channel hidden in the left and right
			surround channels; all others are
			discrete
DTS	1.0–5.1	yes	similar to Dolby Digital in practice,
			though it uses a different technology
DTS-ES Matrix	6.1	mostly yes	the center rear channel is a matrixed
			channel hidden in the left and right
			surround channels; all others are
			discrete
DTS-ES Discrete	6.1	yes	all 6.1 channels are discrete

Once the SSP-600 has decoded the signal it is provided in the appropriate manner, you still have some options as to whether you would like additional processing of the signal.

This point is sometimes confusing. The first thing any surround processor must do is to recover the various channels that were intended to be delivered into your home. This might be a single mono signal, or a Dolby Digital Surround EX soundtrack with 6.1 channels, or anything in between; it may have been delivered to your home via a satellite receiver, a cable set top box, or a simple DVD disc. Regardless, the first task is to recover as many channels as are being delivered, with great accuracy and fidelity.

Having done so, however, it may make sense to provide further processing, after the fact. Hence the notion of post-processing.

For example: movie soundtracks are created in highly-standardized environments, in order to offer excellent performance in large, commercial theaters. Acoustically, your home is a radically different environment than that for which the movie soundtracks were optimized. Therefore it makes sense that you might want to compensate for the differences between the intended environment (a commercial theater) and your actual environment (a domestic living room or family room).