You don't have any XLR cables to try for yourself? If the Sony is fully balanced then yes you will hear a significant improvement. I have a fully balanced cdp, Cary 306 Pro, going into a VTL 6.5 preamp, also fully balanced, and the difference was like 50% better w/ XLR.
Is Sony XA-5400ES fully 'truly' balanced?
Just purchased new Sony XA-5400ES SACD player. Sounds fantastic after a couple hundred hours. Currently running 'inexpensive' Kimber Hero SE interconnects. Was wondering if any benefit should/would be realized from changing to XLR balanced cables? Not sure if the Sony is a fully balanced unit? The preamp IS fully balanced Krell KCT.