Guys, calibrating to the "0," or reference level, mark doesn't mean that one listens with the volume level set at that mark. As far as I know, calibrating to the "0" mark, by having "0" equal 75dB, merely provides a means of referencing your volume to a standard (dat's why it's called "reference" level
![](/boards/images/graemlins/smile.gif)
).
If you have two guys who have calibrated their receivers to the "0" mark, and the both say they listened to a disc at -20dB, you know they both listened at the same volume (20dB lower than the reference volume). If I calibrate to the "0" mark and you don't, then my -20dB mark and your -20dB mark are two different volumes, and yours isn't actually -20 dB from reference.
That is not to say that you can't set your reference point at whatever mark on the volume dial you wish. But if you don't use the "0" mark, the receiver's volume dial is inaccurate, and you can't equate your receiver's volume setting to anyone else's, excepting those who've calibrated to the exact same setting.
By the way, I listen, most often, between -27 and -16 dB from reference, depending on the source material and how loud I want the material to be. I have
never listened at reference level (though I've come close, once or twice
![](/boards/images/graemlins/cool.gif)
), and few people I know have.