Fosi Audio- P4 Mini Preamp Headphone Amplifier

Equipped with three stereo RCA input ports, this preamplifier allows easy switching between multiple audio sources such as CD players, DACs, network streamers, turntables (with external phono stage), and other line-level devices. This flexible connectivity ensures that your entire audio setup can be accessed without constantly unplugging cables, making it ideal for users with multi-source home systems.

Experience outstanding audio clarity with ultra-low Total Harmonic Distortion (THD+N ≤ 0.003%), ensuring your music remains clean and faithful to the original recording. The high signal-to-noise ratio (≥110dB) combined with an ultra-low noise floor (≤9μV) and high crosstalk rejection (≥105dB) delivers crystal-clear sound reproduction, even in complex or high-resolution listening environments.

Fine-tune your sound with dedicated bass and treble tone controls, offering a wide ±12dB adjustment range for both frequencies. Whether you prefer warm lows or sparkling highs, this preamp adapts to your taste. A tone control bypass switch is included to preserve a pure signal path when EQ isn’t needed. Additionally, three selectable gain levels let you match output to various amplifiers or speakers, ensuring optimal volume and clarity without distortion. The user-swappable op-amp design further enhances customization, allowing audiophiles to personalize the sound signature with their preferred op-amp chips.

The unit features both RCA line-out and pre-out connections, allowing it to be paired with a variety of audio gear. Easily connect to powered speakers, subwoofers, or external power amplifiers to build a more dynamic and complete audio system. This versatility makes it ideal for both casual listeners and audiophiles seeking a scalable setup. Perfectly paired with the V3 Amp, it delivers an exceptional synergy for balanced performance and full-range sound clarity.

With its sleek black brushed-metal finish, this preamp seamlessly complements modern home decor and fits easily into tight spaces such as desktop setups, entertainment units, or studio racks. Despite its small footprint, the build quality and design give it a premium aesthetic and tactile appeal.