How do you listen?

Right now I am listening to jazz.. about 75db.

My symphony seats are 8th row center (on aisle on left). The crescendos are too loud. But when there is a soloist the violin sound hole or piano sounding board is pointed at me. This makes the solos amazing and perfectly blended with the orchestra. It also allows different instruments to be clearly discernible while allowing for complete integration when large parts of the orchestra play simultaneously. Also, my line os sight is above the stage so I can see the players.  So, very occasional over saturation these are the perfect seats in the house. 
The general rule is 7th row center, but over time I found these a tad too close in symphony hall I attend.

When measuring the volume level you typically listen to your system, is there a consensus on which frequency weighting to use? I find that C weighting can display a reading between 5-10 dB higher than A weighting depending on how much content below 500 HZ is present in any given piece of music.  

Never on headphones, due to tinnitus. 
Volume depends on the disc and the material. 

With my ears never use headphones, ever.......

With my speakers/ controlled room/ears...

Never use my 7 pairs of headphones anymore since that event...

i apologize
limomangus
I could not resist....