Hybrid Vacuum Tube/USB DAC Headphone Amplifier for High Performance Headphones

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HIFIMAN EF-100 Hybrid Vacuum Tube/USB DAC Headphone Amplifier

The HIFIMAN EF-100 Headphone Amplifier Offers an Incredible Listening Experience

The HIFIMAN EF-100 is a powerful hybrid headphone amplifier and integrated amplifier. Housed in its compact chassis lie three independent amplifier sections: a vacuum tube input stage works as a shared preamp, a Class AB headphone amplifier, and a Class T speaker power amplifier. Benefiting from vacuum tube technology, both headphone amplifier and power amplifier sound warm, smooth, detailed and musical. Working as a hybrid headphone amplifier, EF-100 can produce a 2w output under a 32 ohm load so it can easily drive many high performance headphones. In addition, EF-100 can also serve as a hybrid power amplifier to drive speakers of moderate to high efficiency. In power amplifier mode, the amplifier output line is fully independent from the digital amplifier line used in the headphone amplifier. Driven by front stage’s vacuum tubes, EF-100 combines the warmth vacuum tubes are known for with the high efficiency of a digital amplifier. It is the best of both worlds. When EF-100 is used as a power amplifier, it can give 4.5 watts per channel so it can drive HIFI speakers of moderate to high efficiency. At last, with its versatile design EF-100 can bring music to life from a variety of sources for both headphones and speaker applications.

The HIFIMAN EF-100 Headphone Amplifier Offers an Incredible Listening Experience

General Features:

  • Premium audiophile hybrid vacuum tube headphone amplifier
  • Features 3 independent amplifier sections:
    • Vacuum tube input stage that functions as a preamp
    • Class AB headphone amplifier
    • Class T speaker power amplifier
  • Listen through your favorite headphones or a pair of speakers
  • Integrated 3.5mm, stereo RCA and type B USB inputs
    • USB input and built-in DAC allow you to stream CD quality music from your computer
  • Full size front stereo headphone output
  • Binding post speaker connectors
  • Vacuum tube input stage brings warmth, detail and spaciousness to your music
    • Utilizes a single 6N3J dual triode vacuum tube input stage
  • High output headphone amplifier designed for use with high performance headphones like the HiFiMAN HE-560 and HiFiMAN HE-6
    • Class AB solid state design
    • Output Impedance: 32-300 ohms
      • Output at 32 ohms: 7.8V, 2W
    • Signal-to-Noise Ratio: 95dB
    • Frequency Response: 20-20,000 Hz
  • Drives speakers with moderate to high efficiency levels
    • Class T solid state design
    • Power Output: 4.5W x 2 into 4 ohms
    • Frequency Response: 20-20,000 Hz
  • Dimensions: 7-7/8"W x 10-3/4"D x 3-3/4"H
  • Authorized Internet Dealer
  • 1-year Manufacturer's Warranty

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

Also found as: EF100

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
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.
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.

Specials with this Item

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Warranty and Return Policy

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

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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 EF-100

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Hybrid Vacuum Tube/USB DAC Headphone Amplifier for High Performance Headphones


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