7Band Sound Equalizer with Integrated Headphone Amplifier Designed for professional audio enthusiasts and everyday users, this 7band sound equalizer offers precise frequency control, quality amplification, and full headset compatibility for mobile voice calls, music, and studio applications. Key Features and Specifications: 3.5mm Interface Compatibility Supports 4pole 3.5mm plugs, allowing direct connection to headsets with microphones. Enables clear and reliable voice calls on mobile phones without the need for adapters. Includes an additional terminal connection point for flexible integration into audio setups. Accurate 7Band Equalization Control Provides a ±12dB control range across seven distinct frequency bands: 60Hz, 150Hz, 400Hz, 1kHz, 3kHz, 6.5kHz, and 15kHz. Ensures finetuned sound shaping from deep bass to crisp highs. Built using TI or TL074 components for stable, quality audio performance. Performance Preamplifier Utilizes the classic 4580 operational amplifier with 5X amplification (14dB gain). Designed for accurate signal boosting with low distortion. Input impedance is 20KΩ, output impedance is 600Ω, ensuring compatibility with a wide range of devices and minimal signal loss. Powerful Earphone Driver Built with NE5532 for balanced headphone amplification, using a 47 earphone driver circuit. Capable of easily driving various headphone types with adjustable output height to match user preference. Practical Applications: 1. Mobile Communication Enhancement Ideal for users who need clear, amplified audio during mobile voice calls while using headsets with integrated microphones. 2. Studio and Live Audio Processing Suitable for musicians, audio engineers, and podcasters to shape and optimize sound with precise tone control in recording or live performance environments. 3. Quality Music Listening for audio enthusiasts seeking enhanced listening experiences, allowing fine adjustment across all key frequency ranges to match individual preferences or specific music genres. With robust equalization, reliable amplification, and wide compatibility, this unit delivers professionalgrade sound control while remaining flexible for both mobile and stationary audio setups.