The “Quietness” control adjusts the perceived loudness of the sound for normal (less than concert-level) playback volume.
Many stereo systems have a “loudness” knob that boosts the bass and extreme treble frequencies, making the music sound louder. The InguzEQ quietness control is similar but more subtle. It makes the overall sound quieter but more natural.
The exact change depends on the setting. With quietness set to zero, there is no change to the original signal. With quietness set to 10, a timbre equialization is applied appropriate for listening to concert-level sound at a very quiet level. At intermediate settings, a more gentle equalization is applied, depending on the difference between two ISO223 loudness curves.
If you usually listen to music at a reasonably high volume, then you should leave the quietness control at 0 or 1. If your normal listening volume is relatively quiet (enough to listen but still conduct a conversation), then try a setting of 4 or 5 — you should hear a more natural musical balance with this loudness-based equalization than “flat”.
