I currently have one pair of Silver Reference II and two pairs of XLO Signature 2 all balanced cables. The XLO is a more dynamic cable and has more energy in the higher registers(some can associate that as brightness) than the Acoustic Zen Silver Reference II, and I am using both XLO cables throughout my main system. The "softer" sounding XLO now connects the subwoofer to the preamp.
The point to be conveyed here is I find the Silver Reference II to be a softer sounding cable in comparison to the XLO. Sonus Faber Grand Piano speakers especially the Concerto version are warm and slightly rolled-off in the treble and I'm little surprised you are getting a silvery(bright) cymbal sound as opposed to a bronze(warm) sound. If that's the case I suppose Audphile's advice may be a safer bet.
The point to be conveyed here is I find the Silver Reference II to be a softer sounding cable in comparison to the XLO. Sonus Faber Grand Piano speakers especially the Concerto version are warm and slightly rolled-off in the treble and I'm little surprised you are getting a silvery(bright) cymbal sound as opposed to a bronze(warm) sound. If that's the case I suppose Audphile's advice may be a safer bet.