I'm curious. What is your "normal" listening volume?

I try to keep it between 85dba and 90dba when I am doing an extended listening session. As a prior poster mentioned every recording has an ideal playback level but even if it is above 90 I usually will lower the volume so I don’t damage my hearing further. 

Great posts.  I also find each album/song has its own ideal volume but generally i listen between 65 and 75 db unless no one is home but me.  Then around 95 db.

Peaks are at around 80db, but it seems that as my stereo system became more refined (mostly more costly components) I lowered the volume. My usual is in between 70-75db. 

The Center for Disease Control (CDC) provides a free sound level meter app for both Apple and Android phones. This app is calibrated for levels set by the National Institute of Occupational Safety and Health:

NIOSH Sound Level Meter App | Noise and Hearing Loss | CDC

The NIOSH Sound Level Meter and several other apps can be downloaded from your device's App Store by simply typing NIOSH into the search box. 

Warning: at the rate that federal agencies seem to be disappearing I wouldn't wait long to do this. 

For Dynaudio loudspeaker owners Dynaudio provides several free apps, including a sound level meter, that can be downloaded from your phone's app store. Simply type Dynaudio into your App Store search box and a list of free apps will appear. 

Some method of generating a steady state tone at multiple set frequencies will be important and there are a number of CD's and downloads available for this, some free and some costing small amounts.

I own and have compared the above two tools and there might be minor response variances between them in your use.

What's important though is to use any sound level diagnostic device, including calibrated microphones and software of course, to measure and establish a baseline for future comparisons.

When testing or changing any ear or room acoustics having a set of baseline measurements recorded can be invaluable for detection and/or confirmation of differences that might or might not be audible.

Ugh! The last sentence above should read:  When testing or changing any gear or room acoustics....