Re your comment:.

Isn't that odd? I thought the loudness compensation was based on F&M
curves describing our *hearing*, not our loudspeakers! Compensating
for loudpeakers bad bass extension is a another kettle of fish,
entierly, right?

Per.

You are absolutely right, but all the average consumer knows about the
loudness button is that if you push it you get more bass, and that's what
they use it for. In the 80s I sold speakers kits that had good bass output.
Our customers usually bought them as replacements for speakers that had that
had weak bass response, and often called back complaining about the horrible
boomy bass from their new speakers. Invariably we found that they had the
loudness on and the bass all the way up. We asked them to set their
controls flat for a week and report back, and we found that the problems
disappeared.