Difference in sound between day and night. Help!

At words poetic I'm so pathetic.

I have noticed the night/day effect for at least the past 25 years since I first bought electrostatic speakers. I tried all sorts of remedies, but as millercarbon said earlier - anything you do to make it better in the daytime will also make it even better at night. And there are lots of things you can do.

I accepted the phenomenon years ago, but one thing still really puzzles me. It involves making a digital transfer of a vinyl record in the daytime, and the same transfer again late at night, on highly optimized equipment. You would think that the one made late at night would sound better on playback, no matter when it was played, on the same system, night or day. But in my experience it doesn't. Both copies sound relatively the same on playback, no matter what hour of the day or night they were made. But they both sound better played back at night. The one made at night sounded better at the time of recording, when monitored on speakers or headphones, but not on playback. In other words, the day/night effect does not seem to be recordable. Specifically, the daytime deterioration does not seem to be recordable. Does this indicate that the only components which suffer daytime deterioration are the loudspeakers (or ears)?

I'd be interested to know if anyone else notices the same, or maybe the opposite effect?

@whostolethebatmobile It sounds better at night because your hearing/brain is more sensitive at night. It is physiological and evolutionary. You've done the test. 

You’re close. Very close. The brain is analogous to a sensitive radio transceiver in the sense it picks up background information whether you are aware of it or not. It’s conscious and subconscious. Thus, when there’s less extraneous information floating around at night in the form of electromagnetic waves your brain’s 🧠 Signal to Noise Ratio is higher. It’s an illustration actually of mind-matter interaction. There’s no substitute for Signal To Noise Ratio. Mystery solved! This is not to say there can be other additional reasons why things sound better at night. 

Thanks for your thoughts geoffkait and noromance. I agree with the main points and with the likelihood of additional factors being at play, including the unknown.