ANY good speaker, ANY great system: when played at low volume, YOUR EARS, anybody’s ears, do not have a flat curve. Low volumes, you hear less volume of lows and highs, relative to everything in between. Science!
The ’Loudness’ circuits (filters, equalizers) were developed to compensate for EVERYBODY’s ears hearing less bass and less highs AT LOW VOLUMES. EVERYBODYS (any age, not tinnitus, simply facts).
Play Jazz at a decent volume, the bass player, and the imaging of where the players are you get terrific imaging from your awesome system, specifically the bass enhances the enjoyment of Jazz..
Now, lower the volume: the bass player is kind of gone relative to the other players.
Engage the Loudness feature, bass player is back.
Raise the volume: remember to disable the Loudness feature, or you will have a bass bloated sound.
That is why I like the Chase’s AUTOMATIC and PROGRESSIVE engagement of the Loudness circuit. Raise the volume, the Loudness eq is automatically disengaged.
Like I said, vintage equipment ALL had Loudness feature. Implementation varied.
My Yamaha Receiver has two volume controls. 1st you set ’normal’ volume with one volume control, then leave it alone. You use the other volume control which raises the volume with zero loudness added, you lower the volume, and the Fletcher Munson curve: low bass and high treble are boosted, progressively as you lower the volume with that control.
My Fisher Tube Preamp has a loudness switch. As you lower the main volume, you notice the bass is getting weak. You engage the loudness circuit, and it ’adds’ the bass back.
REPEAT: every speaker remains unchanged, everyone’s ears hear less bass, ’loudness’ electronically boosts the bass SENT TO to your wonderfully flat speakers.
