Definitive Technology SoloCinemo XTR Quick Reference Manual page 23

Connection Method #3:
All sources into your TV with analog output from the TV set to your
SoloCinema XTR.
Some older TV's have only an analog output connection. In this scenario, the TV
does all the switching between sources and the SoloCinema XTR is always set
to INPUT #4. A Dolby Digital or DTS digital audio signal cannot be passed
through a TV's analog output connection. The best audio signal quality that can
be reproduced using this method is two-channel stereo audio.
The surround processing circuitry designed into SoloCinema will simulated a
surround experience from the analog stereo input, but will not be as effective as
when processing a true digital 5.1 surround signal. This method works, but won't
offer the best performance, and is the least-preferred connection method of the
three described here.
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