System sounds better at night?


I have noticed that my system sounds MUCH better at night, after about 10pm than at any other time of day. It is clearer, more open and transparent, with a blacker background. Another audiophile told me that this is not real, it's just that there is less noise in the household at night. I disagree in that what I hear (or don't hear) is not simply due to less ambient noise but rather cleaner sound. Will power line conditioners simulate these effects during the day? Has anyone else noticed this and what is the most effective way to get better sound during the daytime? Serious responses only, please.
jc4659
@celander  Did you purchase in US and if so from whom?  I'm guessing this is $$$.
A lot of RF is airborne, that why cell phones work indoors, and generated by microprocessors in electronics so power conditions isn’t going to help that. Just saying. 
Daytime enjoyment of one’s audio system is hampered by so many things. Solar radiation, demand on the power grid of local utilities, consumer products being used in home, increased airborne particulates, etc.
For those who use the Inakustik AC-3500P, are you plugging your power amp into this conditioner?  What about your digital gear?
For my system, a pair of ATC SCM20-2 active monitors (built-in amps and x-overs), Jay’s Audio CDT2 MK2 CD Transport, Theta Digital DSPro Basic IIIa DAC and Oppo SE83 blu-ray player are plugged into the unit. My preamp, Teo Audio’s The Liquid Pre, is a passive unit that does not require power.