I believe Jond's understanding is correct. Your best bet to get the full bandwidth DSD offers is to use the Sony's analog outs and put no further digital equipment between the Sony's output and the amplifiers. If the DEQX converts the analog signal to pcm, you've lost your bandwidth; I don't know of any digital crossover that uses DSD, though I'm willing to stand corrected, because I don't know very many.
I'll leave it to cable experts to tell you whether a balanced interconnect would restrict the bandwidth--I would think not. The only limitation on a cable should be the signal it's fed.
I'll leave it to cable experts to tell you whether a balanced interconnect would restrict the bandwidth--I would think not. The only limitation on a cable should be the signal it's fed.