Features * Adjustment knob with locking function for precise and smooth operation. * Supports independent adjustment of subwoofer frequency, output power, and volume to meet personalized listening needs. * Universal half-DIN size for easy installation and compatibility with most car dashboards. * Built-in active gain preamplifier with adjustable input sensitivity for superior sound quality. * Supports independent sensitivity adjustment for left and right channels, achieving more precise soundstage positioning. * 20dB dynamic headroom ensures distortion-free music playback even in high dynamic ranges. * Equipped with gold-plated RCA input connectors for low impedance, low loss, and stable transmission. * Three stereo RCA output connectors for direct connection to amplifiers, subwoofers, and crossovers. * Built-in main/auxiliary input selection switch for quick signal source switching. * 7-band graphic equalizer, center frequencies: 50Hz, 125Hz, 315Hz, 750Hz, 2.2kHz, 6kHz, 16kHz * Gain/Attenuation range: ±18dB * Signal-to-noise ratio: 100dB * Subwoofer selectable frequencies: 60Hz / 90Hz Frequency response: 10Hz - 50kHz (±1dB) Maximum output voltage: 9V Total harmonic distortion: 0.005% Input sensitivity: 50mV - 3V Net weight: 1.6 lbs Target users: A must-have for true car audio enthusiasts, sound connoisseurs, and modification shops. Allows for fine-tuning of the in-car sound field, frequency bands, and bass intensity to create a personalized listening experience. Applicable scenarios: Original car audio upgrades, amplifier/preamplifier tuning, independent subwoofer control, multi-channel sound field tuning, sound quality optimization, vocal/bass/treble fine-tuning.