Listening at Night vs. Day

I almost exclusively listen to my system at night. On occasion when I have listened to it during the day, I thought that it seemed to sound just a little better than it did at night. A little smoother and spacious. If I accepted that this consistent experience wasn’t my imagination, then perhaps my ears were more “rested” and less “fatigued” during the day than at the end of a long day.

Several weeks ago, a friend dropped by during the day to hear my system for the first time. I had been telling him about Shostakovich’s Ninth Symphony and its uncharacteristic cheerfulness for a Shostakovich symphony (and a striking contrast with his eighth, for sure!). So, I played for him a DSD64 recording of that symphony, which I often listen to at night, and it brought tears to my eyes! For the first time! What phenomenon was this?

Recently, I was listening to my system around 10pm, and on this particular night, it sounded to me like it did during the day. I think that I have a possible explanation, but it is likely to be met with skepticism.

My house has a solar panel system with a battery storage system. Typically, the panels start producing electricity at around 8am. When the panels produce more power than I use, the excess goes to charge up the batteries. When the batteries are charged to 100%, the excess is sent to the grid for credit. Typically, the batteries reach 100% charge around noon. After the sun starts to descend, household power is sourced from the batteries, until the batteries are drained to a 50% reserve that is maintained for grid outages. (The 50% reserve is programmable; it would just as easily be set to 90% or 10%.)

So, on a typical sunny day, the system provides for home power for almost all of my “on peak” hours. During the summer, the system may provide all my power from 8AM to 7PM, after which power comes from the grid. In the non-summer months, the solar system will l provide power until midnight or later, because the air conditioner, the greatest sink of power, is not operating.

The solar panels provide DC current to an inverter, which provide AC current to the house. Similarly, the battery units (of which there are two) have integral inverters that deliver AC current to the house.

I have come to believe that my stereo sounds better when it is being powered from the house inverters than it does when it is being powered from the grid. On the night mentioned above, a summer anomaly occurred. A rainstorm kept outside temperatures very low for this time of year, and the air conditioner ran very little, allowing the battery reserve to power the house into the night, whereas on the previous and following hot days, power was sourced from the grid at this time of night. I took notice because of the unconscious contrast with the previous evening.