Preamp output voltage?

Could someone please explain preamp output voltage? What effect (if any) does it have on amplifier performance, S/N ratio, dynamic range, and most importantly, subjective listening? I have an old Adcom GTP-500II tuner-preamp with a rated output of 2.0V RMS and a peak output of 10.0V RMS. I am considering replacing the Adcom with a new AV surround receiver, and I would use the pre-outs to power my front KEF 104.2's with an Adcom GFA-555II amp. I am looking at the Outlaw 1070 receiver, but it only has a pre-out voltage of 0.76V. The Yamaha RX-V657 receiver claims a pre-out voltage of 2V. Will either of these receivers (or any other receiver) be likely to sound as good, driving the Adcom amp, as the Adcom tuner-preamp for 2 channel music?