Specification :
Condition: 100% Brand New
Power supply voltage: DC10-24V single power supply DC
Frequency range: 22Hz-300Hz.
Audio input: mono or dual channel
Audio output: mono
Standard circuit board: approx. 78 x 32 mm/3.1 x 1.3 inches, thickness: 1.6 mm.
Material of printed circuit board: super hardness FR-4 fiberglass board
Plate Fixing Hole Center Spacing: 70x24mm, Hole Diameter: 3.2mm
Potentiometer Shaft Center Distance: 32.5mm
Approximate weight: 32g/1.1oz

Package List:
1 x filter plate.
2 x Screw
2 x Gasket
2 x Knob Cover

Note:
This board is a heavy bass preamp board. It will not sound when it is directly connected to the speaker. It must be connected to a pure end stage power amplifier board to make an active subwoofer. The power of the pure final stage power amplifier plate is selected according to the shock level of individual needs. The higher the power of the pure final stage amplifier. the bass effect. The so-called low-pass filter plate filters the treble parts above human voice, and retains the low-frequency part to zoom in and improve bass reproduction power, and does not hear human voices and high-frequency instrument sounds playback.