Which preamp helps lower listening sessions?

Just discovered my system sounds better at low levels. For years I was using a ss preamp but now I moved onto a tube unit. It's resolution is not excellent as I am used to with the simaudio p-5, which preamp will give me the same pleasure as this audio experience a2se preamp but with better resolution. Also the bass lessens at these levels- which preamp will compensate for this without having bass treble controls since I want a straight wire preamp without equalization. Also don't want artificial sounding bass or exagerated but natural sounding bass.