System sounds different at different times Why?


I have a perplexing and cofusing situation. Im convinced that during the day light hours the response of my system is abnormal, subtly so or not: bass is reduced (the amp doesnt even get warm at high volumes) its not as clear or tight, imaging and separation are not up to snuff, mids sound forced and crunched but sometimes/usually in the late (after midnight) evenings everything sounds like what I expect... Im never sure exactly how much of a difference because Im not sure if its occurring or not, its sometimes very subtle. When its extreme its obvious. I cant AB day to day to much time in between listening sessions As far as ABing day to evening , I can be listening at moderate levels during the day and late into the evening thinking ok no changes This is what it is supposed to sound like anything else is me. . Change a CD or the next track will play and suddenly wow that sounds completely different. Low end blossoms separation and staging are superb. Even my GF heres the difference. No rhyme or reason appears to be completely random and arbitrary. The only constant is that it just never sounds right during daylight hours. Usually
Worse, I have no point of reference.
heres what I got what troubleshooting Ive done. CAL transport, Monarchy DAC, Bryston amp B&W 802 Matrix 3 bi wired (which are for sale by the way) and a jitter box.I have switched from unbalanced to balanced sends, coax, optical balanced digital sends,cleaned connects, flipped flopped substituted yelled at cables used a tone generator to listen to tones and sweeps (useless by ear just as useless with crappy mic on pc) Looks like 1k sounds like 1k so...Tried a couple of Hail Marys. No definitive results.

Besides ambient temp Im now thinking its a power delivery issue. Hundred year old apartment with grandfathered ac. I get 120 at the outlet wired correctly but i have about 23 v between neutral and ground No voltage drop when stereo is on but when turn on a motor on same circuit (say a fan) drops about 3 volts Ok That was a lot of typing Any ideas? thanks
mc
itacud
In my opinion this happens- to all of us- and the reasons include:

1. Your mind (the state thereof)
2. Your body (one possible reason-cortisone levels are generally higher at night)
3. Power delivery/ noise levels versus daytime.

Just my opinion.
Happens to me too, just not as severe as it seems to you. Your 100 year old year old building makes it worse.

At night there is far less electricity running through the lines outside coming to you. People have shut down their TVs, washers, dryers, etc. You are getting cleaner power.

This has been brought up many times. There are other reasons why. Do a search.

Start here:
http://forum.audiogon.com/cgi-bin/fr.pl?htech&1123125310&read&keyw&zzsystem=sounds=better=at=night
Perhaps power sags during the day - perhaps there is an industry nearby that is on the grid - is there more light during the day - this may affect your mood?.

My system sounds the same day or night.
Get a PS Audio Power Plant Premier. Since I got one my system sounds great all the time.
I have the same problem and have closely monitored humidity (35 to 40%) and power at the outlet - which is 120 volts, never lower. So I eliminate those factors. Maybe there is more to clean power that volts I do not know.

I think cleaning the cable ends is the main contributer to improving the sound but still when they have all been cleaned and Pro Golded I can still get sub par sound. I do not believe the state of mind theory (OK maybe a little). So what is it?

I can say I notice it a lot more since I have used Audio Note speakers, when I had my JMR Trentes I never noticed this phenomenon and the rest of my equipment is mostly Audio Note so go figure.
I noticed something similar, after an hour or two of listening, it was like a speaker driver was binding and causing some subdued tones. Nothing you could really say for sure that it was hapening or describe accurately, but made me think something was wrong. About 4 months ago I put in a dedicated outlet with hospital grade and dedicated grounds. A noticable difference immediatly for the better and I no longer experience any changes after lenthly listening. GG
Itacud said "As far as ABing day to evening , I can be listening at moderate levels during the day and late into the evening thinking ok no changes This is what it is supposed to sound like anything else is me. . Change a CD or the next track will play and suddenly wow that sounds completely different. Low end blossoms separation and staging are superb."

And now for a different point of view.
I say it is because you change volume levels, therefore you have no reference point to anything you are listening to, and that your system is not tuned properly to eliminate this effect. If you are interested search my threads for volume levels and its affects.
Bob
Itacud, in addition to some of the comments above, ambient noise will also effect how you perceive your sound.

Regards
Paul