What's Going On?? Sound changes every night


O.K., this is what I'm experiencing: Some nights my system is superb and I just get sucked in and have to force myself to stop. This will be for 2-3 night and then all of a sudden, the next night or three, the music looses life and I can't get involved. The sound looses high end sparkle and extension. Things sound closed in a bit and percussions instruments that the night before were right in front of me are now fake with a closed in and shelved down presentation. Cymbals no longer sound like wood sticks on bronze but as if someone threw a blanket btw me and them.

Is this a power conditioning problem? I use a hospital grade outlet but not a dedicated circuit and no power conditioners. Or could it be my DAC which is a Perp Tech w/ Level 2 WrightMods and cryo treament. When the system works right I couldn't be happier but it seems something weird is going on every few days or so. Could it possibly be coming from the local power company and I need some sort of powerful line conditioner?

System:

Merlin TSM-MX speakers
REL Strata III subwoofer
Air Tight ATM300 stereo amp
Joule-Electra LA150 pre-amp
WrightModded Perp Tech DAC
CEC transport or Marantz SE 5 disc changer as transport
Cardas Golden Reference interconnects
TG Audio speaker cables
tomryan
Same thing happens here. What is typical is the loss of low end clear bass and a muddying of midrange frequencies during the day. Best time always seems to be after midnight and especially without all the air conditioners running in the Summer months. I have no dedicated AC or any power conditioning and a $6.00 power strip has everything plugged into it straight to the wall outlet. One day the sound's full and rich and on the next day it can be awfully tinny and rough. Would your own Honda Generator be the answer?
I have dedicated AC with seperate ground, and still have what you describe.
Rather than guess, or have the expense of an electrican, why not take a VOM (Volt Ohm Meter) and plug into your wall socket - just leave it on while you're listening. When the sound starts to change for the worse, check what you line voltage is. If it's going above or below 120 volts when it sounds bad, then you have a correlation and can start working on it - Variac (Monster AVS 2000), power regenerator (PS Audio) or whatever.
If you're at the end of a cul-de-sac with a 50 year old house, the neighbors could put a sag in your current playing with their arc welder or something.
My Monster AVS2000 has seen a 4 volt drop on some very cold nights, and a 6 volt on warm nights (I'm in CT).
For the price of a VOM ($10 at Rat Shak if you don't already have one), it's a cheap way to see whether there's a correlation.
Good Luck
ah... Tomryan, by the way you answered, now I DO STRONGLY belive it's your "mood". With a tempper like that, your listening taste will change by mood.