Volume control vs. attenuation control


Can someone please explain the difference between a volume control on an amp and an attenuation control on a pre amp. My pre amp manual states to leave the attenuation control at 0db for critical listening. Some amps have volume controls built in. So if I wanted more "play area" in the pre amp volume control (when playing CD's so the music isn't blasting at the 9:00 position) would it be better to lower the amps volume control or the pre amps attenuation control?
markpao
It's highly advantageous to play around with both controls in order to match amp and pre. I would consider myself lucky to have such ability. You want enough gain in each to optimize sound quality and not too much as to cause distortion. And you want pre to have enough in relationship to amp's sensitivity but not so much as to overdrive the amp causing undue distortion. Hopefully other members will give a more technical explanation, but optimum settings will be dependent on speakers (and source). Will be dependent on how demanding are the speakers.
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All volume controls are attenuators. Gain stages amplify the electrical signal and attenuators, either before or after a gain stage, reduce the level of the signal.

The setup up Markpao describes will allow him to play with both attenuators to achieve the combination of lowest signal to noise ratio and flexible volume control settings.
In your case you're describing gain control vs. attenuation control on your preamp section that should be set to the best possible volume range that you want to operate your volume control for ex 7...12 o'clock. If you feel that you get distortions on the most of your listening range try to adjust one way or the other untill you get the most of sound and leave the gain control untouched.
I would try the combination you like, then do some critical listening. A/B between that and their suggested setting, and see if you loose/gain anything. If it sounds the same (better possibly?), go for it.