Ehm... I thought you were talking about your own creation ^^
There is no backing tracks of this band available yet. Although on this kind of studio recording & mixed mp3, taking appart the instrumental or the vocals would be awful to hear.
I guess you tried this with Audacity (high pass filter stereo>reverse>mono etc..) the rendition is terrible unless the original file was mixed in soft and simple ways.
Actually, such an mp3 file taughly mixed/recorded is like a chocolate cake; when its realisation is ascomplished you can't tear the flavour appart anymore, nor the eggs and the chocolate inside. Everything is already mixed there's no backup unless you're in possession of the individual parts recordings.
As I said you'll only be able to split the main stereo file, reducing vocal's part Hertz and adding some effects... But anyway it won't be legal
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So you've got two options, first is to request professional sound engeneer who will play/copy/sequence each single track.
Second is to do it manually, converting the *.mp3 into a MIDI file and then to import it into a MIDI sequencer where you'd use the appropriate combination of MIDI controllers (keyboard, drum, wind, tactile, etc.)
Please note that sequencing a song like this is time consuming and takes a lotta work, I can not do it.
Keep on google'in`na purpose to find uploaded backing tracks.
tOrF