@deep_333 Sterile? In relationship to most tube amps that would be better described as accurate. I suspect you would not like Boulder amps either.
@jl35 Really? Do you have a measurement microphone? Do you have the experience of listening to systems with various target curves? Do you know what a flat response curve sounds like? Most audiophiles have never heard a system that images correctly. Many audiophiles are operating on mythology.
IMHE, accurate equipment in summation leads to better performance in all respects. Many systems are the end product of compounding errors and will never perform at the state of the art. These systems may suite the taste of some listeners, but taste is a moving target. If a person's system is on the bright side when he or she hears an accurate system it will sound dull. If you listen carefully to the bright system the cymbals will be in your face like an ECM recording, not accurate. Not only this, but a system's characteristics change with volume. A system that sounds fine at 85 dB will sound harsh at 95dB. Then there are recordings that are mixed to various volumes. The Funkadelic recordings were mixed for high volume and sound awful at 85 dB, but turn the volume up to 95 dB and they sound great. ( for early 70's recordings)