I discovered something rather interesting....
Before when I used the test tones from my receiver for sound level calibration using an SPL meter, I was seeing about 75 dB on the meter from all speakers when my receiver's master volume was also set to 75.
While using the Sound & Vision calibration disk however, I was seeing 75 dB on the meter from all speakers when my receiver's master volume was set to only 70.
Just an observation here. Any comments are welcome!