Hello Anonymous

You can adjust the bass and treble via the menu (displayed on the connected TV/screen):

Adjusting the sound (Sound)
Here you can adjust the sound.

Press OPTION.
An option menu screen is displayed.

If "HEOS Music" is set as the input source, an option menu for online music is displayed. Select "AVR Options..." and then press ENTER.

Use the up/down cursor to select "Sound" and then press ENTER.
The "Sound" screen is displayed.

Use the cursor left/right to switch the sound control function on or off.
On:

Allow sound control (bass, treble).

Off
(default):

Playback without sound control.

Select "On" in step 3 and press the cursor down to select the sound range to be adjusted.
Bass:

Adjust the bass.

Treble:

Adjust treble.

Use the cursor left/right to adjust the sound and then press ENTER.
-6 dB - +6 dB (default: 0 dB)

Best regards

Patrick

Use the OPTION button on the remote and select "Tone". It's only available if you disable Audyssey's Dynamic EQ in the audio settings though.