S/N ratio Balanced input vs. Unbalanced input

Hi, is it normal that signal to noise (S/N) ratio at rated output of balanced input (XLR) is lesser than unbalanced input (RCA) ?

eg. Accuphase E280 , S/N ratio balanced is 96dB, unbalanced is 107dB.

Also E280 , at preamp stage , dB gain : balanced/unbalanced to pre output is 18dB gain, power amp stage dB gain : 28dB, total of 46dB.

What about other integrated amplifiers specs for comparison ?

S/N ratio (balanced) :

S/N ratio (unbalanced):

Preamp gain :

Poweramp gain:

auronthas07-08-2022 1:12am

o_holter Details Discussions Posts This discussion Message User 975 posts 07-08-2022 at 12:53pm Copy Comment URL Report Comment Edit Delete So its not the connections. And the hiss is constant, regardless of the volume level?
auronthas OP Details Discussions Posts This discussion Message User 79 posts 07-09-2022 at 06:30am Copy Comment URL Report Comment Edit Delete @o_holter yes, the hiss is constant, with no variance on volume, the hiss is there with power standby on my DAC Ares II , only it’s gone when I unplug the power cord
o_holter Details Discussions Posts This discussion Message User 975 posts 07-09-2022 at 08:49am Copy Comment URL Report Comment Edit Delete What happens if you disconnect the DAC from your amp? Hiss still there?
auronthas OP Details Discussions Posts This discussion Message User 79 posts 07-09-2022 at 02:36pm Copy Comment URL Report Comment Edit Delete No more hiss if DAC is disconnected
kijanki Details Discussions Posts This discussion Message User 4,426 posts 07-09-2022 at 08:14pm Copy Comment URL Report Comment Edit Delete If hiss comes from the DAC and is independent of the volume pot, then likely DAC is injecting some electrical noise into amplifier. I wouldn't worry about it, since not too many amps are completely quiet with the ear on the tweeter.