I calibrated my 6.1 home theater system at 55dB using my SPL meter and the test tones from my receiver. Does this matter? I'm afraid to turn the volume up so that it reads 75dB on my SPL meter from where I sit because that would be very loud and I don't want to blow my speakers. This is just temporary until I get the Sound & Vision calibration DVD in the mail, but won't those testones be pretty loud too? Can I calibrate lower than 75dB for that disc? I wouldn't ever be listening at Ref level anyway.