I was wondering about the same question so searched and found this old thread. Will add to it instead of starting a new thread.
I just purchased a dB meter to check how loud it is at my listening position. I found that depending on the music most of the time it’s between 50-70 dBA. I thought it would be higher. I tried 3 different devices and the results were fairly consistent. My doctor told me to keep it under 70 to preserve my hearing with my old guy ears.
Does anyone else use a meter to check or do you rely on the volume/loudness setting on your system?