listening volume?

One item not discussed so far is whether the numbers people have mentioned above are "A" weighted or "C" weighted. "A" weighting mimics human hearing, which doesn't have a flat frequency response (lows and highs do not sound as loud as the midrange frequencies). "C" weighting is flat. This means when you are using a sound level meter to check full-range sound, the "C" weighting will give a much higher number than the same sound measured with "A" weighting. OSHA standards are based on "A" weighting. 

I have traditionally measured my volume using the "C" scale. For full-range music this can give a dB number that is 10 or more higher than the "A" scale.  My sound level meter lets me switch between "A" and "C" while my phone app doesn't indicate which it uses, but when compared to my meter the phone app appears to use a "C" scale.  Note that may vary with which app is used. 

This means that the 85 dB figure I mentioned may only show as 75 dB or less on the "A" scale when playing music with a lot of bass and high frequencies. As such, this is an important detail when looking at dB numbers. 

The LOUDER the BETTER 

A clarification of the above -- the 10 FB difference noted between "A" and "C" is heavily dependent on the music being played. I spent some time switching my meter back and forth and for material that isn't bass heavy the difference may be more in the 5 dB range. If one was playing music on a table radio with little bass he difference may disappear. 

Needs to be 75-80 db to hear all the details.

in the low to mid 70s when people are home.  When by myself, I'll do low to mid 80s for an hour to 1.5 hours.