The thing with bitstream is you need to know what the source is bitstreaming, and the speaker needs to be able to handle that format. Chances are the bitstream data is 6.1 channel[1], or it may be DTS. (Katana supports up to 5.1 and Dolby)
Source [1]:
https://www.reddit.com/r/PS4/comments/3k0jbi/can_the_ps4_output_71_audio_through_the_optical/
And then the 5.1 sounding like stereo part, well thanks to techidiot's extensive testing, when I read between the lines one of my guesses is that the Katana only processes the stereo data and then throw the rest of the channels away, and then do magic on the stereo data to make it feel as if it is surround, but it's still stereo nonetheless.
Well the above is just untested hypothesis. But strangely nobody has seemed to test or notice that fact. Could you be the one? Just play some sound that only exists in the rear channel.
PCM audio stream as for Dolby part.
I still remain skeptical about the Dolby decoding.
Take note Katana is using PC Dolby Audio, just flip to the rear you can see it. Some Sound bar uses Dolby Digital surround which means which means support for Dolby D.
As for Katana is really hard to tell whether it support Dolby D or not.
One thing for sure, when I test katana VS my own soundbar.
Actual soundbar you can hear the surround environment clearly especially rear channels like what Wwenze have mentioned.
In the sense like Batman Arkham games.
Just turn the characters around, on actual soundbar you can hear rear and distance firing/talking.
On katana, it is different can only hear what is around the character or front channel only.
I have been honest with the Katana but my finding were ask to be taken down.
Word of advice, if you feel katana either disappointing or having issues.
Remember Lemon Law is within 6 months, you can ask for refund or exchange depending on the retailer you brought.
However Katana is still a decent UMS speaker for PC, if you want to use it with TV/console best get a actual soundbar.
