HIFIMAN EF2A + Sonic Electronix Bonus Pack 3

Vacuum Tube Driven Headphone Amplifier/USB DAC + Extended Warranty & Exchange Policy

Here's What You Get with the Bonus Pack 3:

  • HIFIMAN EF-2A Headphone Amplifier/USB DAC
  • 3-Year Sonic Electronix Warranty (Headphones Only)
  • Extended 180 Day Exchange Policy (Some Exclusions Apply)

  • We apologize

    This item has been discontinued

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    HIFIMAN EF2A Hybrid Vacuum Tube/USB DAC Headphone Amplifier

    The HIFIMAN EF2A Headphone Amplifier Offers an Incredible Listening Experience

    Plug the HiFiMAN EF2A into one of your computer's USB ports and prepare to be impressed. This compact digital-to-analog converter/headphone amp bypasses your computer's built-in DAC and audio circuitry — processing your digital music files outside the noisy environment of your computer for far better sound quality. The EF2A's vacuum tube headphone amplifier brings your tunes to life, imparting smoothness and clarity. You'll hear more dynamics and detail that you can really savor on your headphones. The EF2A also includes an analog audio input so you can enjoy improvements in sound with another music source. This is one component that looks so cool, you'll absolutely want to show it off on your desktop.


    Vacuum Tube Driven Headphone Amplifier/USB DAC
    Quantity: 1

    General Features:

    • Compact desktop headphone amplifier/DAC
    • Provides significantly more dynamics and detail to your headphones
    • Utilizes two 6J1 vacuum tubes for the amplifier input stage
      • Injects smoothness and clarity into your music to really bring it to life
    • Burr Brown PCM2702 digital-to-analog converter provides exceptional sound quality
    • Rear USB input allows you to connect to your computer and bypass the built-in DAC and audio circuitry
    • Rear stereo RCA audio input allows you to enjoy your music from other audio sources
    • Full size front stereo headphone output
    • Rotary volume control
    • Sleek, durable metal chassis
    • Acrylic top panel
    • External power supply included
    • Dimensions: 5-11/16"W x 4-1/4"D x 3-1/8"H
    • Authorized Internet Dealer
    • 1-year Manufacturer's Warranty


    • Input Impedance: 47,000 ohms
    • Output Impedance: 32-300 ohms
    • Output:
      • @ 32 Ohms: 3 v, 320 mw
      • @ 150 Ohms: 6.2 v, 256
    • Frequency Response: 20-20,000 Hz
    • Signal-to-Noise Ratio: 95dB
    • Distortion: 0.2%

    What's in the Box?

    • HIFIMAN EF-2A Headphone Amplifier/DAC
    • Two 6J1 Vacuum Tubes
    • AC Power Adapter
    • 5' USB Cable
    • User Guide

    Note: HiFiMAN products can only be shipped to customers in the United States

    3-Year Warranty for Headphones & Portables Valued Between $100.01 - $200

    3-Year Sonic Electronix Warranty for Headphones & Portables Valued Between $100.01 - $200
    Quantity: 1

    General Features:

    • 3-year Sonic Electronix Warranty - on Headphones and Portables valued between $100.01 to $200
    • Coverage begins on date of purchase
    • No hassle warranty that comes with all the bells and whistles and no hidden gotchas
    • Comes fully equipped with a 5-day service guarantee and 24/7 Online access to your warranty contract
    • Protection from ALL mechanical and electrical failures
    • Note: Sonic Electronix warranties are currently only valid in the United States. This includes all 50 States and Puerto Rico.
    • 1-year Manufacturer's Warranty

    Extended 180 Day Exchange w/ 60 Day Return on Select Headphones

    Extended 180 Day Exchange w/ 60 Day Return on Select Headphones
    Quantity: 1

    General Features:

    • If you don't love your new headphones, exchange them within 180 days no questions asked!
      • Only applies to the headphones
      • Must be returned without physical damage in original packaging with all accessories
        • Defective products still eligible for standard 1 year exchange policy
      • Standard 60 day return policy still applies

    Note: Package only valid when purchased with select headphones

    Headphone Amplifier Specifications

    Digital-to-Analog Converter (DAC)
    A Digital-to-Analog converter (also known as a DAC) converts a digital audio signal into an analog signal. This is especially helpful for listen to music from digital sources, such as iPods and smart phones.
    Frequency Response
    The range of frequencies the amplifier will reproduce (lowest frequency to the highest). Bigger is better, meaning the wider the range, the better. The optimal range is 20 - 20,000 Hz (which is the range of human hearing).
    20 - 20000 Hz
    Input Connection
    This is the manner in which the headphone amplifiers receive an input audio signal.
    Stereo RCA
    Input Impedance
    This is the input impedance of the headphone amplifier.
    47000 ohms
    Output Connection
    This is the manner in which the headphone amplifier will output the audio signal.
    1/4" Plug
    Number of Outputs
    Some headphone amplifiers have a built-in splitter so multiple pairs of headphones can be connected to it. The number specified here is the number of headphones that can be connected to the amplifier.
    Output Power
    This is the output wattage of the headphone amplifier. It is measured in mW.
    320 mW
    Output Impedance
    This is the output impedance of the headphone amplifier.
    32 ohms
    The width of the item from left to right (side-to-side) measured in inches.
    The height of the item, measured from top to bottom, in inches.
    The front-to-rear depth of the item, in inches. If the item is angled or slanted, this value is the bottom measurement.
    Amplifier Style
    Some headphone amplifiers are designed to be portable and others are meant to be placed on a desk. This will tell you what style of amplifier this item is.

    Warranty and Return Policy

    Parts Warranty Duration
    1 year
    Labor Warranty Duration
    1 year
    Warranty Provider

    Summary of Customer Ratings & Reviews

    Rating Distribution

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    Product Summary


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    Internal SKU


    Internal Product ID


    Sonic Electronix Wiring Guide

    Wiring Diagram Legend

    Warning: The image depicted shows the resistance change when wiring multiple subwoofer terminals. Please refer to your subwoofer's owner's manual for the proper wiring of its terminals. Sonic Electronix, Inc. is not responsible for damage caused to your audio system or vehicle due to improper installation. Please call tech support at 1-877-289-7664 if you require additional assistance.

    Product Name: HIFIMAN EF2A + Sonic Electronix Bonus Pack 3

    Item Added to Cart

    HIFIMAN EF2A + Sonic Electronix Bonus Pack 3

    Vacuum Tube Driven Headphone Amplifier/USB DAC + Extended Warranty & Exchange Policy


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