Features The frequency dividing board consists of the Linkwitz-Riley filter The Linkwitz-Riley is mainly used in active filter circuits, such as many sophisticated multi-channel electronic sound systems This filter is characterized by up to a fourth-order attenuation slope Linkwitz-Riley filter has a very flat phase response Adopt NE5532 Op AMP chip, it has stable performance Specification: Condition: 100% Brand new Filter Type: Linkwitz-Riley Filter Frequency Point: 310HZ/3.1KHZ (20HZ-310HZ for bass output, 310-3.1KHZ for midrange output, 3100-20KHZ for treble output) Attenuation Slope: -24dB/Oct Board Structure: 6-Channel output, treble, bass, midrange Op AMP Chip: NE5532 Size: Approx. 173 x 79mm / 6.8 x 3.1in AC Transformer Power Supply Range: Double 14 to double 19V Connector: Audio input / crossover output -2 gold-plated lotus socket x4   Package List: 1 x Amplifier Board Note: New-style and old-style are shipped randomly Package List