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Fosi Audio P4 HiFi Preamplifier: 3 RCA Inputs, EQ/Bypass, Swappable Op-Amps, Treble & Bass Tone Control For Audiophile Systems

Fosi Audio P4 HiFi Preamplifier: 3 RCA Inputs, EQ/Bypass, Swappable Op-Amps, Treble & Bass Tone Control For Audiophile Systems

Regular price $119.99 USD
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SPECIFICATIONS

Brand Name: Fosi Audio

Certification: CE

Channels: 2 (2.0)

Features: Preamp,Home Audio Preamplifier

High-concerned chemical: None

Input: 3 RCA Inputs

Maximum Power Per Channel: NO POWER

Model Number: P4

Origin: Mainland China

Output: RCA+PRE OUT

Package: Yes

Power Adapter: 12V/1.5A



 
 
 
 

Fosi Audio P4 HiFi Preamplifier: 3 RCA Inputs, EQ/Bypass, Swappable Op-Amps, Treble & Bass Tone Control For Audiophile Systems

Features:

  • Studio-Level Signal Accuracy | ±0.1dB Frequency Response & 105dB SINAD
    Pure, untainted reference-quality sound, tailored for discerning ears.
    With a flat frequency response from
    20Hz to 20kHz (±0.1dB) and a 105dB SINAD (Signal-to-Noise Ratio + Distortion), the P4 achieves nearly lossless signal transmission. Featuring Japanese Elna audio capacitors and Omron gold-plated signal relays, it eliminates current noise to ensure every detail is faithfully reproduced, rivaling the performance of high-end preamps costing tens of thousands.

  • Three-Input Hub | One-Touch Switch Between CD, Vinyl, and DAC
    Say goodbye to constant plugging and unplugging, and build a multi-device Hi-Fi system.
    Three independent RCA inputs allow you to simultaneously connect a turntable (with external phono preamp), CD player, and high-end DAC. With the infrared remote, you can easily switch between sources with a single button press. Whether you’re enjoying your classic vinyl collection or streaming Hi-Res music, simply press a button to experience seamless listening.

  • Gain Staging + Motorized Potentiometer | Precision Matching for Power Amplifiers
    Perfectly adaptable from low-sensitivity to high-resolution systems.
    3dB/6dB/9dB Gain Adjustment:
    Low Gain (3dB): Protects sensitive power amplifiers from overload distortion.
    High Gain (9dB): Reduces system noise floor and enhances dynamic range.
    The ALPS vintage motorized volume knob uses an analog potentiometer structure with left-right channel error <0.1dB, ensuring smooth, unbiased volume control.

  • Tone Control Freedom | Adjustable EQ + Replaceable Op-Amps + Bypass Mode
    From precise monitoring to personalized sound tuning, a dual-purpose machine.
    Midpoint-adjustable bass and treble: Compensate for room acoustics or enhance rock/jazz atmospheres.
    Hi-Fi Bypass Mode: Direct signal path with the EQ circuit bypassed, delivering uncolored, high-resolution sound.
    Replaceable op-amp design: Compatible with popular dual-op-amp chips (such as MUSES02/OPA2604), allowing you to easily customize the sound signature to your preference—whether it's a "warm tube-like" or "crisp, analytical" tone.

  • Minimalist Control Aesthetic | Full-Function Remote + Compact Metal Chassis
    Ideal for both desktop and rack setups, blending seamlessly into high-end systems.
    Comprehensive remote control:
    Power on/off, switch inputs, and adjust volume/mute without the awkward "bending over to find the knob" experience.
    PRE OUT Output: Connect an active subwoofer for a 2.1 system, or link multiple amplifiers for multi-room audio.



Highlight:

  • Model: P4

  • Power Adapter Output: 12V/1.5A

  • Product Adapter Input Voltage Range: AC 110V - 240V

  • SNR ≥ 110dB

  • THD ≤ 0.003%

  • Treble adjustment range: ±6dB

  • Bass adjustment range: ±12dB

  • Input Mode: 3 RCA

  • Output: RCA/AUX

  • Frequency Response: 20HZ -20KHZ((±0.1dB)



Package Include:


*P4 Preamplifier x1

*Power Adaptor x1

*User Manual x1









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