Originally Posted by Sledge
Why would this device need output jacks? An internal switch from speakers to headphones?
Well, yes... sort of.
In the connection diagram the Realiser is "located" between the preamp outputs and the amp(s) inputs for the true loudspeakers. Thus you have 8 discrete channels of analog input and the matching 8 discrete channels of analog output... going right through the Realiser like a wire.
This is required for both (a) calibration process for the room/ear files via loudspeakers, where the Realiser feeds sweep signals to each amp/loudspeaker, and (b) bypass of the SVS processing when you simply want to listen to sound through your real amp/loudspeakers instead of through your headphones.
The headphone outputs of the Realiser are the "tap" on that analog connection pathway between preamp outputs and loudspeaker amp inputs, which is what facilitates SVS processing. The result of SVS processing is then delivered to the headphone outputs of the Realiser, in both analog (after internal D-to-A conversion) and digital forms.
The analog headphone outputs of the Realiser then go to the analog inputs of the headphone amp. Optionally, if you prefer you can instead use the digital headphone output of the Realiser connected to the digital input of an external DAC, and then connect the analog output of the DAC to the analog input of the headphone amp. Note that the Realiser's analog headphone outputs are RCA, whereas the digital/DAC optional path from Realiser to headphones can (and probably would) utilize XLR connections, or RCA depending on DAC hardware.
Same story holds regardless of whether you have separate components (preamp or processor with separate amp(s) for your loudspeakers) or receiver (which provides preamp outputs to feed external amp for loudspeakers). The preamp-level discrete 8 channels of decoded output from whatever is your preamp-level "source" box, whatever that is, goes to the 8 main analog inputs of the Realiser.
This set of 8 discrete channels of analog inputs and outputs connections through the Realiser allows for both of the following situations:
(1) true "pure analog pass-through" of all 8 inputs to all 8 outputs when the Realiser is either (a) powered off entirely with power cord pulled from the wall, or (b) "off" by being placed in stand-by mode with the remote. This is genuinely like a "wire".
(2) "digital pass-through" using suppressed internal Realiser electronics so as to perform no SVS processing, but still involving A-to-D conversion upon entry from the inputs and D-to-A converson before exiting from the outputs, when the Realiser is powered on. In this mode of operation there is NO output to the headphone jacks, but only to the 8 main analog outputs and thus sound is heard only from the loudspeakers. Again, there is NO SVS processing applied to the sound fed to the 8 main analog outputs but there is A-to-D and D-to-A conversion involved.
Note that "digital pass-through" mode of operation (to listen through loudspeakers only) while the Realiser is powered on can be initiated by both (a) pushing the PASS button on the remote to specifically stop supporting the headphones and revert to loudspeakers, or (b) taking the headphones/head-tracker off and rotating them forward 90 degrees or so in order for there to be no IR signal received by the head-tracker receiver on top of the TV. This latter technique is typically used to do an A/B-comparison of true loudspeaker sound vs. what SVS has provided while listening through your headphones.
This digital pass-through (i.e. suppression of SVS processing and inhibition of headphone output) can also occur if you turn your head left or right far enough so that again the IR signal emitted by the head-tracker mounted on your headphone headband is far enough off-center so as again not to be received by the receiver.
NOTE: if you truly want to listen to "highest-quality analog audio", say from a 2-channel audio CD through your 2-channel decoder/preamp/amp and then on to your zillion dollar 2-loudspeaker system, you would want to use "pure analog pass-through" mode (by placing the Realiser "off", i.e. in standby). This completely bypasses the internal A-to-D and D-to-A conversions within the Realiser which cannot be avoided when using "digital pass-through" mode (i.e. when the Realiser is "on").