Question on DTS 7.1 and 5.1 audio tracks - both required?

[ripper2020]

I ran into something new when ripping Pacific Rim. It has an audio track for both dts ma 5.1 and dts ma 7.1. My question is, do I need both? I only have a 5.1 surround sound and I'd rather not rip two separate tracks if 7.1 down mixes to 5.1, but I don't know if it does. In other words, if I only rip the 7.1 track and play it through my receiver, what will happen to those two extra channels? Will they be lost? Or be mixed into the two rear channels?

Again, I'd rather not rip both to keep my rips smaller but I'd like the option of using 7.1 in the future. Thanks for any info in advance.

[aecad]

Since you have 5.1 (and I assume your receiver handles DTS) then just select the 5.1 audio. If by chance you mux in the 7.1 audio how it will play back depends on your receiver.

[Romansh]

Receivers aren't as dumb as to discard channels. So as long as it can play the track, it will downmix it to 5.1.

Edit: that being said, the presence of two tracks does suggest the 5.1 mix differs from a simple 7.1 -> 5.1 downmix (that, or the Blu-ray authors are stupid), so for a 5.1 system if might be worth picking the 5.1 track anyway.

[ripper2020]

Hmmm, thanks for the feedback. It seems like I should just rip both audio tracks to be safe. Thanks again.