Video Asylum

Posted by David Aiken (A) on November 04, 2007 at 21:56:55

In Reply to: RE: Question on Dolby Digital Signal Driving "Logic" posted by JoeLip on November 04, 2007 at 21:23:49

Are you sure the problem is the Sony TV? Here in Australia most hi-def off air broadcasts are only stereo anyway. I've yet to come across a 5.1 broadcast signal and I don't know how my set-top box would handle that. One day I may find out but all my local off air broadcasts seem to be stereo only.

If the TV is passing the signal in bitstream, I would have thought it would simply be passing the signal it receives, not converting it to stereo. If it's converting a surround signal to stereo and passing a stereo bitstream, then it's decoding the original bitstream, downmixing to stereo, then re-encoding into a Dolby bitstream and I don't think any TVs do that. If the TV is passing the signal in PCM, then it could be downmixing but then the receiver should show the signal as PCM, not Dolby, since the Dolby decoding has already been done and it's no longer in that format.

If the TV gives you the option of bitstream or PCM digital out, choose bitstream and let the Onkyo do the decoding. That's your best bet of preserving surround channels if the broadcast has a multichannel surround soundtrack. If the broadcast is stereo, that's all you're going to get whether you ooutput in bitstream or PCM digital format, or in analog either for that matter.



David Aiken