A week ago, my electric company came out and put a tracer at the meter. Today, they removed it and sent back some graphs of THD for voltage and current. THD for voltage is easy to interpret. It varies in a fairly constant manner throughout the day as the first chart shows, with lows around 2.4% and highs around 3%. Very similar between the two channels/lines. THD for current is more nuanced. Which is not surprising as it's impacted by my own electrical habits which vary widely throughout each day. The second graph shows THD patterns over the same seven days. The third graph shows a single day, Jan 12. Looking at the third graph, daytime THD seems to be 5-10% on Ch1 and 15-25% on channel 2. Not only does Ch1 have considerably lower THD (at least on this day) but it's more consistent. (Note the big dip at 4pm on Jan 12. That's when I threw all the sub-breakers and left them off for 10 min. The engineer said current THD at the meter was zero during that time and voltage THD was unaffected.) I'm not quite sure what the patterns in current THD correspond to. The regular spikes are probably the fridge right? And if I zoomed in on the day I did laundry... I imagine I could make that out pretty clearly. No AC this time of year. But lots of heater use. Those seem like the biggies in terms of regular patterns and use. I'm also not sure how to interpret these patterns to determine which side of panel is Ch1 and which is Ch2. I'm asking for additional graphs. Why did I do this? I'm getting a dedicated 20A audio circuit installed soon. I had this test performed (for free!) to help determine which channel to use and also what my power conditioning needs might be. Seems to me I want to put the dedicated circuit on Ch1 but I'm not 100% confident in that. And I have no reference point for THD on voltage or current for a single family home. So I don't know what's low and what's high. Also it's worth noting that the ten single family homes on my block all share a common transformer So is my power clean? Or is it dirty?