auna PRO PP-2215A Mode D'emploi page 19

Bass boost control: Boosts frequencies around 50 Hz up to a
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maximum of 12 dB.
Treble boost control: Boosts frequencies by 10 Hz to a maximum
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of 12 dB.
Volume control: Controls the amplification. If the volume seems
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too low, turn the control towards MAX.
Frequency control: Frequency section (50-250 Hz) for high-band
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filter
EN
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