Hello - sorry for digging up this old thread but I figured why open a new one?
I read the initial post and first response and I was quite surprised by it.
I hope someone could help me understand by going a bit more into detail.
My situation:
I have a full-fledged 2160p / BT.2020 / 10bit / HDR10 / DV capable TV.
Recently I bought an S905X box and I am currently helping out a bit to get it to full 2160p / BT.2020 / 10bit / HDR10 output capability by testing and supporting the devs.
It's almost there.
You might already have guessed what's coming now...
I have an old 1080p-era AVR that I still like a lot (Onkyo TX-NR818, mainly because of Audyssey MultEQ XT32).
Of course it cannot pass those UHD signals, so I'll have to either...
a) buy a replacement AVR if I want to keep HDMI "HD-audio" or
b) just use the S905X optical out and listen to regular Dolby Digital or DTS.
When I encode my Blu-rays, I always keep a "S/PDIF compatibility" track, so either the usual 1,5mbit/s DTS core or the Dolby equivalent additional 640kbit/s AC3 track.
I always assumed those pre-compressed tracks would be superior in quality to Kodi live-transcoding to AC3...
However, the first response sounds to me like the exact opposite is the case?
Do I actually get a HD-audio quality via S/PDIF if Kodi transcodes live to Dolby Digital?
How is that possible? Or did I misunderstand the first answer?
Is AC3 not limited to 640kbit/s and also limited to the rather ancient compression (compared to the likes of opus or AAC-HE)?
Also, I recently decided to compress my HD-audio tracks (Dolby TrueHD / DTS-HD MA) to opus at 640kbit/s VBR (8 channel) and 480kbit/s VBR (6 channel), which is more than enough to be transparent to me.
If live-transcoding to AC3 is the "magic" I hope to have correctly understood it is, do the same rules apply for live-transcoding from opus, FLAC, HE-AAC and all the others too?
I'd really appreciate answers and explanations!