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Features

Overview: The HiFiMAN EF-5 is a hand-built high performance hybrid headphone amplifier, designed for use with high-end and hard-to-drive headphones. It combines vacuum tube sound quality with solid-state technology to deliver outstanding audio performance. The EF-5 comes with a separate DY-1 Power Supply, which can be positioned beside or stacked below the EF-5. The EF-5 has a stereo RCA input on the rear panel. On the front, you'll find a 1/4" headphone jack, power switch, and rotary volume control. The EF-5 and DY-1 each have a black acrylic faceplate and a brushed aluminum chassis.

Vacuum Tube: The EF-5 uses the 12AU7 Full Music vacuum tube at the input stage to significantly improve the condition of the source signal. The tube has a flat frequency response and a high signal accuracy. The tube is packed separately inside the box, so you will need to install it through the provided hole in the EF-5's top panel. When installed, the tube protrudes approximately 5/8" above the EF-5.

Note: The 12AU7 tube takes approximately 60 seconds to warm up. A blue LED behind the front panel will glow when the EF-5 is ready to use.

Key Components:

• Vacuum Tube: RCA Clear Top 12AU7
• OP-amp: JRC5532 OPA275

Specifications:

• Input Impedance: 50k Ohms
• Output Impedance: 2-2k Ohms
• Output: @32 ohms: up to 15 V
• Frequency Response: 20 Hz to 30k Hz
• Signal-to-Noise Ratio: >95dB
• Distortion: 0.2%
• Power Supply: 110 to 240 Volts
• Dimensions:
  • EF-5 Headphone Amp:
    • Width=4.344"
    • Height=2.25" (2.875" w/tube)
    • Depth=9.5"
  • DY-1 Power Supply:
    • Width=4.335"
    • Height=2.003"
    • Depth=9.5"