Full detailed sound at 30 - 40 - 50 dB


I love the nuance you can hear when listening to music at loud volumes, but unless no one is home, it’s not considerate or feasible to listen at such high volumes. Plus I just had a baby so everyone is always home and volume levels are limited to 40ish dBs. 

Any recommendations for getting the most detail at these volumes? Additional gear or recommended integrated amps?

My NAD 7175PE has a loudness button which boosts the treble and bass a little, and that certainly helps things in the Kitchen. 

My living room amp is a Rega Brio-R which doesn’t have any tone controls. 

Any thoughts? Thanks!
leemaze
@atmasphere maybe off topic but do you have a suggestion for a preamp to use with a passlab xa30.5 that will be used with 96db sensitive speakers?
Sure- one of our preamps will do that nicely :) (they're balanced).
The Pass amps are pretty easy to drive though- I would expect it to work with many different preamps.
I have Ascend Acoustics Sierra 2 speakers, and they sound great at lower volumes. I'm powering them with a Rega Elex-R, and live in a condo, so rarely listen at loud levels. I've had about eight pairs of good quality speakers over the years and these sound the best of any of them at lower volumes. Good luck.
@gdhal

Thank you for your ringing endorsement of Grateful Dead Music to produce a more peaceful and well-balanced child. I don’t have children, but I would recommend Dead for folks with a new puppy. My one-year-old is a jammin’ Deadhead dog, who asked me to buy him a tie-dye bandana for his birthday...(He is also a Jazz fan...) Like father, like son.
@cheapbob

You're welcome.

Cat on a tin roof, dogs in a pile
Nothing left to do but smile, smile, smile 
I recently built a pair of back-loaded horn speakers using full-range single drivers and had a similar challenge as the OP since they are in a system in an upstairs room that I’m gradually converting into a small listening room. So low volume listening levels are important. What I discovered after experimentation using my own (SS) gear and borrowing gears from my friends was that a low powered tube amplifier with a very low damping factor - high output impedance, and using basic speaker cables, produced the best sound quality at low volume. The trade off however is the lower bass gets a little boomy at higher volumes. Ironically, the amplifier that gave the best result was a very moderately priced Chinese unit with only 8.5 wpc. Next best was a Decware integrated. So like everything else in life there’s always a trade off.