At exactly 7:00 pm in Sydney, the electrical grid changes for the better. It goes bad about 4:30 PM, gradually. But the change at 7:00 PM is startling, it only takes about 2 minutes to go from really bad to really good. It will continue to get better until 11 PM, but most of the benefit happens exactly at 7:00 pm. I find it hard to believe that a change this sudden (literally 2 minutes) and pronounced is caused by neighbours all suddenly switching off their ovens simultaneously...?
Also, there are three different types of electricity. Morning and early afternoon, late afernoon, and evening. In the morning and early afternoon, the sound is fabulous, but it's "crisp" and images are "etched" and very solid and present in the room, but little depth. In the afternoon (4:30 PM - 7:00 PM) the sound is horrible (although better now with STB Platinum). In the evening (7:00PM onwards) the sound has lots of depth, realism and detail, but none of that intense "etching" that I actually find quite interesting and very engaging. It's like the air is being torn and ripped by the instuments.