Yes, you can hear it. In my system, I have even found that there are noticeable differences when reducing the voltage by inserting dummy batteries.
Basically, as I reduce the voltage, the soundstage becomes a bit smaller, more distant and less resonant. It was WELL worth the time finding the ideal setup for me:
48 volt 8 foot Volcano speaker cables running @24 volts
72 volt 1 meter Colorado XLR from DAC to Preamp @12 volts
72 volt 2 meter Colorado XLR from Preamp to monoblocks @24 volts
I found these differences were evident right away, but did take a day or so to completely settle.
Before experimenting, I thought the sound was slightly too in my face qand slightly gauzy with batteries connected, and a bit hard and thin with no batteries.