... Should I be concerned?

Hello to all...

So here I am, back again, still trying to "tune" my budget rig to the max "best to me sound":

CD only setup with over 10 yr old Marantz SA8001, into a Tube Line-level preamp, into a Parasound HCA-750 power amp, with homemade speaker cables (12g solid core copper wire, twisted; bare wire on both ends), at back of speaker same wire bent into C-shapes as jumpers... Speakers are KEF Q1s (luv'um).

On the back of the Parasound, there are volume knobs (so you could use the amp direct without a preamp) which I have up full ( as recommended to me thru another topic line). When I play music, I have so little volume adjustment available: I can't really get past 8 o'clock (from starting at 7) without it being too loud... 

One question I have is: will I be degrading the sound if I " adjust" the volume pots on the rear of the power amp, so that I can have more control over the volume knob on the pre? I guess I' be shooting for a 10-11 o'clock on the pre, and I'll assume it means a great decrease in the setting on the power amp.

Could another tact be: to replace the volume knob/pot with an articulated one, one that would click increases as I turn it?

This may be a foolish question - but any info or suggestions (other than criticism or sarcasm) would be greatly appreciated... Best Wishes to all - Be Well.