1. Control range: 7-band equalization circuit with a 12dB control range. Equalization frequency bands: 60Hz, 150Hz, 400Hz, 1KHz, 3KHz, 6.5KHz, 15KHz, utilizing TI or ST TL074 components. 2. Basic parameters: 7-band sound equalizer preamplifier gain with a classic 4580 operational amplifier providing 5X amplification (14dB). Input impedance is 20KΩ, output impedance is 600Ω. 3. Headphone compatibility: NE5532-based balanced headphone amplifier designed for 47 earphone driver circuits, capable of driving various headphones with adjustable output. 4. 3.5mm interface: 3.5mm input supports 4-pole plug; output connects to headset with microphone, compatible with mobile phone voice calls. Includes additional RCA terminal input. 5. Aluminum alloy construction: 7-band audio equalizer housed in durable aluminum alloy material offering high strength, corrosion resistance, and stable performance. Powered by DC 5V–12V, dual-channel audio output. Suitable for use with car audio systems, mobile phones, computers, game consoles, and other devices. Color: Black Material: Metal Package Contents: 1 x Headphone Amplifier Mixer Note: The package includes only the items listed above. Other accessories are not included. Note: Lighting effects and display differences may cause slight variations between the product color in images and actual color. Measurement error allowance is +/- 1-3cm.