I’ve had a great experience with my Gryphon Diablo 300 integrated’s low volume performance. I find that I can detect all of its character and tonality coming from my speakers even at the absolute lowest volume setting. I’ve never seen an amp do that before, where these qualities are maintained regardless of volume. There is no loudness control. But I don’t feel it’s needed..
Low volume performance of the Diablo 300 has been commented on in several reviews as well. Not sure of the less expensive Diablo 120 has this trait as well - could be an option.