ну понятно...

а есть вот еще что!

но я где-то видел что параметр bass gain это крутилка -12/+15дб на частоте 30гц. как узнать насколько точно идет привязка к частоте? может это и будет моим HPF?

Adjusting the bass
The bass gain, bass F (center frequency) and
bass Q can be adjusted as follows.
1. Press the A-M button $ and select “BASS
GAIN ”.
2. Press the SEARCH button % and select from
“BASS GAIN ” ➜ “BASS F 50 ” ➜
“BASS Q 1 ” ➜ “BASS GAIN ”.
3. Turn the Rotary knob ( clockwise or counterclockwise
as needed and adjust the gain,
the F (center frequency) and the Q.
BASS GAIN : –6 to 8 (The factory default
setting is “0”)
BASS F : 50Hz/80Hz/120Hz (The factory
default setting is “50”)
BASS Q : 1/1.25/1.5/2 (The factory default
setting is “1”)
4. When the adjustment is complete, press A-M
button $ several times until the