Barcus Berry 3000AE Piezo Buffer Pre-Amplifier with EQ Features external bass, treble and volume frequency controls to allow a wide range of adjustments. Includes a belt clip for unrestricted movement. Input (EQ Flat): Input Interface = RCA unbalanced. Input Impedance = 2.2 Meg Ohms. Maximum Input level = 2.0 vrms. Output (EQ Flat, Volume Max) Interface = 1/4-Inch unbalanced. Impedance = 2K Ohms. THD = .008% @ 1kHz. Noise = -92 dBu. S/N = 100 dB. Bass = +/- 12 dB @ 50Hz. Treble = +/- 12 dB @ 10 KHz. Frequency Response = 5Hz - 30 kHz (+/-1 db). Power supply source = 9 volts @ 380 microamps