Ampeg A-9 Parametric Equalizer


  • Gain
    Turning this control clockwise (in the + direction) emphasizes (+ 18dB = 8 times) the band set by the Frequency control, and turning it counterclockwise (in the - direction) attenuates (-18dB = 1/8) the same. At the center (0 position) of the knob, meanwhile, the frequency characteristics become flat irrespective of the other two knobs' position
  • Width
    This knob controls the width of the frequency band set by the Frequency control. Turning it clockwise decreases (1 octave) the width, and turning it counterclockwise increases (2 octaves) the width.
  • Frequency
    This knob controls the frequency to be emphasized or attenuated. Turning it clockwise shifts the center frequency toward high tones (5,000Hz), and turning it counterclockwise shifts the same toward low tones (70Hz).


made in 1982 and 1983

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  • Input Impedance
    330 K ohm
  • Maximum Input Level
  • Output Impedance
    10 K ohm
  • Maximum Output Level
    + 6 dB
  • S/N Ratio
  • Frequency Characteristics
    20-20,000Hz +/- 1dB
  • Gain
    +/- 18dB
  • Frequency Variable Range
  • Band Width 7-1 octave
  • Power
    Battery DC 9 Volt / AC adaptor
  • Battery Drain
  • Switching System
    "Noiseless" Solid state type
  • Overal Size
    68 (W) x 53 (H) x 120 (D) mm
  • Weight

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