Pappylon, you didn't mention your speakers but, as George says, their efficiency contributes to this as well. Another option that hasn't been discussed is the addition of a pair of attenuators between the pre and power amps. I have successfully used the Rothwells in the past. They come in several values (different amounts of attenuation).
http://www.rothwellaudioproducts.co.uk/html/attenuators.html
Dick
http://www.rothwellaudioproducts.co.uk/html/attenuators.html
Dick