Product details

  • 2021 NEW MODEL: The updated version for BOX X2. Next-generation phono preamp for unrivaled sound quality.

  • JAN 5654W Tube MM Phono Preamplifier: The BOX X4 phono preamp supports 3.5MM AUX and MM turntable input, converting phono signals to Line Level signals with low-noise integrated circuits and high-quality components to remove low-frequency noise ensure clear sound quality. Designed with a grounding post to protect your turntable.

  • Tube Headphone Amplifier & Preamplifier: The BOX X4 is designed with a 3.5MM AUX headphone and RCA output, highly useful beyond imagination.

  • Applicable Vacuum Tube Model: 5654W/6K4/6J1/6J4/GE5654/6AK5/66*In vacuum tubes, etc. You can replace the vacuum tubes to DIY your stereo system. Different tubes with different sounds.

  • What You Get: BOX X4 phono preamp, DC 12V power supply, user manual, our worry-free 24-month warranty, and friendly customer service.

Phono Preamp & Headphone Amplifier with JAN 5654W Vacuum Tubes for MM Turntable Phonograph Preamplifier for Record Player with Volume Bass Treble Control Hi-Fi Pre Amp Fosi Audio Box X4



Specifications

Specifications Details
Model BOX X4
Applicable headphone types 16 Ω
Input Mode MM turntable + 3.5mm AUX
Output Mode RCA + 3.5mm headphone output
Output Active(powered) speakers, Amplifier, Headphones
Frequency Response Standard RIAA
THD ≤ 0.1%
SNR ≥ 70dB
Device Dimension 4.72 x 3.97 x 1.37 inches
DC Input Range 12V
Input Voltage Range AC 110V - 240V
Output Voltage Level 1kHz and 650mV
Power Supply 12V 1.5A


What‘s in the box?

Item Quantity
BOX X4 phono preamp x 1
Vacuum Tubes x 2
DC 12V power supply x 1
User's Manual x 1

FAQs

Please read our FAQs page to find out more.

How to: Choose the right banana plug?
  • Closed Screw Type. All Fosi amplifiers use standard-sized speaker terminals (4mm pins).
  • Easy to wire up and solidly connect to amplifier and passive speaker.
  • If they do not fit, use a little force to tighten the plugs.
  • Fosi Audio Banana Plugs (Copper, Silver/Gold Plated): http://bit.ly/40Djq0U, https://bit.ly/3MkPL8t
  • Please watch tutorial videos: https://youtu.be/6pYhoqDlvNw / https://youtu.be/RGvBgGAwS9k
How to Diagnose Power Supply Failure?
  • The following situations may cause this issue
  • Case 1: The LED on the power supply does not light up; Case 2: Amp/Preamp does not turn on; Case 3: When plugged into the Amp, both light on the amp & power supply start blinking; Case 4: Amp/Preamp make noise; Case 5: Sound shuts off by itself
  • Possible solution
  • Check if the power supply is illuminated when plugged into AC by itself.

    Plug power supply into a different socket.

    Test the adapter with a meter.

    Try a different power supply (within a range of DC input).

    Test the included power supply on other electrical equipment.

    Please watch the tutorial video by clicking on the link provided. https://youtu.be/yCjygS03zTE
What are the differences in power outputs using the 32V and 48V power supplies?
  • Using a more powerful power supply can help prevent distortion.
  • Enables amplifier to drive larger, more powerful, or higher-impedance speakers.
What is a GaN?
  • The GaN supply has a power output of 240W.
  • Offers overload and over-temperature protection.
  • The 48V 5A GaN power supply is also available on Amazon.

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