Bass and Treble Controls

This control is a 270° rotary pop-out/pull knob with the center detent that is shared between BASS and TREB (treble). This control is used for adjusting the system's audio frequency response. The BASS function is operated by first depressing and releasing the knob to the out position. This affects only the lower audio frequencies and has a center frequency of 60 Hz. The TREB function is operated by first depressing and releasing the knob to the out position, then pulling to the fully extended position. This affects the high audio frequencies and has a center frequency of 10 kHz. Center position of a given control indicates flat response over that particular frequency range. Moving a control to the right of center position produces boost, while moving a control to the left produces a cut in frequency range related to that control.

All units incorporate a loudness feature that automatically increases bass bias at low listening levels.

On Auto Tone Control (ATC) models, any adjustment of these controls will activate the MANUAL tone control (ATC) mode and will establish the MANUAL ATC mode as default.

The MANUAL tone mode will be displayed on the ATC models while the radio display is not affected by bass and treble changes on non-ATC models.