Tone controls have a specific purpose..
They provide a simple means for the user to compensate for the tonal balance from a source or program that may have a weakness in its frequency response....
For example, a couple of use cases are..
A. Some early music recordings were bass heavy...
Rather than readjusting the Room EQ an EZ fix is to cut the bass control a notch or 2..
B. FM station's frequency response is high frequency limited, so it may sound too dull..
Rather than readjusting the Room EQ an EZ fix is to boost up the treble control a notch or 2..
SUMMARY
The Room EQ scheme is for achieving a total proper tonal balance
between the Room and loudspeakers, while the tone controls provide a simple means for tweaking the tonal balance differences
between sources and program content..
Just my $0.02..
