The 6th and 7th channel are a matrix of info from the 5.1 surrounds, in time there will be true 7.1 content but not just yet. If you are talking about true 7.1 material then its the decoder for either your DVD or movie Pro/Reciever will control the steering based on your speaker configuration so your not simply missing sound because of fewer speakers.
Surround back spkrs in 7.1 vs 5.1 surround spkrs
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In a 7.1 setup....if a 5.1 movie soundtrack is being played, do all seven speakers engage or just 5? In this instance, does the sound just go to the surrounds rather than the surround back speakers?
In the converse...if a 7.1 soundtrack is being played through a 5.1 system, does the surround back tracks get played through the surrounds? In other words, does all the information get played back in two separate rear channels rather than four surround channels?
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In a 7.1 setup....if a 5.1 movie soundtrack is being played, do all seven speakers engage or just 5? In this instance, does the sound just go to the surrounds rather than the surround back speakers?
In the converse...if a 7.1 soundtrack is being played through a 5.1 system, does the surround back tracks get played through the surrounds? In other words, does all the information get played back in two separate rear channels rather than four surround channels?
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