Originally Posted by R2-M0
Earlier in this thread, it was stated that...
- if you have Secondary Audio turned on, but
- select LPCM as the HDMI Audio output format (instead of bitstreaming) and
- you then play a lossless audio track off a BD, then
- the LPCM output by the 93 will retain the full lossless audio quality (just with the lower quality secondary audio mixed in as applicable)
This is also alluded to in the FAQ as the new feature "Secondary Audio with lossless", and seems like a great set-it-and-forget-it solution. But I'm just trying to track down what the original source for this revelation was. I can't seem to find this particular feature spelled out anywhere in the manual (though it could be I'm just not looking in the right place).
It's easy enough to verify. The compatibility tracks are 48KHz and no more than 5.1. (The Secondary Audio itself is 2.0.)
So if you have verified Secondary Audio mixing (e.g., from a PIP feature) but the resulting LPCM stream is either 7.1 or greater than 48KHz, then you know the primary audio component of the mix must be coming from the lossless track.
Anyway, the short answer is that it is true. In the 93, LPCM output uses the full quality primary track even if Secondary Audio mixing is happening.
Bitstream output *ALSO* uses the full quality primary track, which is decoded prior to mixing in the Secondary Audio. But the result must be re-encoded on the fly back into a Bitstream, and there isn't enough horsepower in consumer gear to do that using a lossless Bitstream. So in the 93, the mixed combo is re-encoded into high bit-rate (1.536Mbps), traditional, lossy, DTS 5.1 48KHz for output. Note that you get DTS 5.1 even if the original primary track is 7.1 or 2.0. For 7.1 the rears are mixed into the sides. For 2.0 the surround channels are silent.