Anyway, the .at3 file has six channels(besides, the .msa file isn't very different from an .at3 file anyway since they use the same codec) yet they can't be either played or decoded anywhere else.
I don't know from where you got that at3, but the way this is structured by my analysis, this is latest ATRAC9 format, i tried using the leaked at9tool 1.6 sdk but it doesn't work to decode. Probably need the latest at9tool from latest sdk 2.508, but that sdk was not leaked as far as I know. I will try other methods to decode this, but this is interesting indeed. From where did you get this file/music? game?
by AnonRunzes at 11:51 AM EDT on September 9, 2016
"I don't know from where you got that at3" From an AlphaTwentyThree script.
"From where did you get this file/music? game?" GTI Club+: Rally Côte d'Azur
The Tekken Hybrid rip at JoshW has three different 6-channel formats. The Tekken Tag Tournament HD folder has 6ch .msf and .aa3 files, while the TTT2 Prologue folder has 6ch .at3 and .aa3 files.
by AnonRunzes at 9:23 PM EDT on September 10, 2016
Download Tekken Hybrid (2011-11-22)(-)(Bandai Namco). The files I described are in there. The 6-channel ones are labeled "51" or "5_1", which stands, of course, for 5.1 surround sound.
by AnonRunzes at 11:42 AM EDT on September 11, 2016
@vajuvaju - Thanks, but I'm more interested in knowing how to decode these 6-channel .at3/.msf files.
On an random note, I've taken a visit to the ffmpeg development channel on IRC and I've sent these same samples there. Perhaps they're working on that too.
I know. This is why I posted these, because providing more files of this type could help decoding them. Fingers crossed that the ffmpeg people succeed.