It's this interview, unfortunatly it is not translated to english. half way he shows the differences between balanced and unbalanced on his oscilloscope.
I was watching a youtube interview with a worker from Metrum acoustics and he claimes it is impossible to achieve more than 90db SNR with unbalanced interlinks. If you want a higher SNR you need to switch to balanced cables. The reason unbalanced interlinks can't achieve more than 90db according...