Loudness - Why has the industry stopped producing amplifiers with this feature any longer?

I am with you twoleftears,

What is really funny, is the people, companies, etc. that eschew this so called "purism" are the first to say Vinyl is the the very best consumer audio format (ignore R-R). What is vinyl? ... it's a minimum of two equalizers, or two compressor/decompressors depending on your view with a variable frequency channel mixer, and a host of other "analog" effects. It is about as far from "pure" as you can get. It takes some serious cognitive dissonance to believe that is pure, but a loudness or equalizer is not.  Some of this is a side effect of believing things not true, like being able to detect small phase differences, etc.

It's almost like the low-fat craze. Never really was any evidence for it, but people blinded believed it, followed it, and got less and less healthy. At least with the THD wars we found out early it was not the be all and end all.

wolf,

I would have one advocacy for measurement. Every few years, someone brings up the very good, but 0 traction idea of playback calibration, usually including reference tones and reference playback level so that the user can listen at the volume level intended to achieve the most accurate playback as intended.

I agree with twoleftears--I think that most of the industry went purist on us.  I particularly miss balance controls, especially now that I've lost a lot of hearing in one ear.   

The amplifier used in the Mapleshade room at CES with the (then) new Gallo reference speakers was a single volume amp designed and built by Pierre’s partner Ron Bowman. No volume control, no tone control. Yeah, baby! 

Less is more.