I am thinking of purchasing -15db Rothwell attenuators to lower the gain from my Rega Brio-R and my Oppo bdp-105. Although my oppo has a variable volume control i’ve been reading mixed suggestions about the variable volume setting. Some say to leave it at 100 fixed setting. Would rothwell attenuators be benificial if plugged into the oppo’s analog outputs? Would there be any negative effect on the sound or just the illusion of compromising sound due to lower volume?