Fosi Audio BOX X4 Phono Preamp Headphone Amplifier/Preamplifier Hi-Fi Pre Amp with JAN 5725W Vacuum Tubes for MM Turntable Phonograph Record Player with Volume Bass Treble Control

Pro-Grade MM Phono Stage with Grounding Terminal: Upgraded from BOX X2, the BOX X4 delivers audiophile-grade clarity for your turntable. Features a low-noise JAN 5725W vacuum tube preamp with MM input and built-in earth terminal to eliminate hum and protect vinyl systems. Ensure your turntable’s internal preamp is disabled for pure analog playback.

Dual-Output Flexibility--Preamp + Headphone Amp：Switch seamlessly between RCA line-level output for amplifiers and 3.5mm headphone output for private listening. Engineered to drive most headphones, ideal for late-night vinyl sessions without disturbing others.

Tube Rolling Flexibility for Custom Sound：Unlock endless audio personalities! Swap stock JAN 5725W tubes with 6K4/6J1/GE5654/6AK5 tubes (sold separately). A DIY haven for vinyl enthusiasts.

Active Bass & Treble Controls for Vinyl Optimization：Fine-tune your records with ±10dB bass/treble EQ – boost warmth for vintage LPs or sharpen detail for modern pressings. Paired with low-noise circuitry to preserve original analog character.

Complete Kit with Extended Warranty：Includes BOX X4 phono preamp, DC 12V power supply, user manual, our worry-free 24-month warranty, and friendly customer service.