Weseixas: In the past , many moons ago , i used to measure avg usually 82-88db , crescendos sometimes hit a peak of 109 db from row 7.
DOB: The answer to this interesting question lies in the attendance of classical music concerts particularly orchestral, choral and operatic ones. You will be surprised to find out that SPL at your ear varies from zero to about 115 dB (if you happen to conduct the orchestra during this attendance as well).
... Keith Howard (Hi-Fi News Sept 2007) made actual measurements of peak power and peak SPL obtained using B&W805, Music Fidelity power amp and classical music recordings.
His measured peak SPL was about 110 dB.
As someone who listens to a lot of classical symphonic music, on minimally compressed audiophile-oriented labels, and who has also listened to Prokofiev's "Romeo and Juliet" from the very first row at Tanglewood (among many other live symphonic performances attended), these numbers all strike me as about right. (Aside of course from the reference to minimum spl being 0, since ambient noise will be much greater than that, both at home and in the concert hall).
I've never used an spl meter, but I've been able to develop what I think is a pretty good sense of sp levels based on sensing the onset of clipping with amplifiers of various power ratings, and extrapolating to spl at the listening position based on speaker sensitivity and listening distance.
Regards,
-- Al
