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Vacuum tube headphone amplifier
Item # 818EF5 | MFR # EF-5
This item is no longer available.
Our take on the HiFiMAN EF5 by Crutchfield's Dave Bar
Get the most out of your high-performance headphones
Just like great speakers, top-notch headphones need high-quality power in abundance to perform their best. Give them what they crave with the HiFiMAN EF-5. This hybrid vacuum tube/solid state headphone amplifier dishes out the kind of juice that can drive even the most power-hungry cans. You'll hear dynamic, detailed sound with the warmth and clarity of tubes, plus the added bass punch and slam of solid state power. Its wide bandwidth, low distortion, and high signal-to-noise ratio make the EF5 the clear choice for discriminating music lovers.
Unique two-box design
The EF-5's dual-chassis configuration uses a separate outboard power supply that helps isolate noise and interference from the amplification circuitry. The amplifier chassis sports a clear plexiglass top and tube cage that protects the dual triode 12AU7 input stage and solid state outputs while allowing you to admire its tidy, well-crafted interior. The two pieces can be placed side-by-side, or stacked to save space. Any way you use it, this is one cool-looking, fantastic-sounding headphone amp you'll be proud to show off.
What's in the Box:
- EF-5 Headphone amplifier
- 12AU7 Vacuum tube
- DY-1 Power Supply
- 39" Power cord (3-prong / IEC 3-pole)
- 30" AC power connecting cord
- 2 Acrylic tube protectors (1 installed)
- Allen-head screws (Length=9mm)
- Owner's Guide
- hybrid tube/solid state design uses a single 12AU7 dual triode vacuum tube input stage and OPA275 solid state opamp output
- dual-chassis design with separate headphone amp and power supply blocks
- high-output design ideal for high-performance headphones, including HiFiMAN HE-500 and HE-6 planar magnetic models
- stereo RCA audio input
- full-size stereo headphone output
- compatible with 2-2000 ohm headphones
- signal-to-noise ratio: greater then 95dB
- frequency response: 20-30,000 Hz
- output at 32 ohms: up to 15 Volts
- THD+N: less than 0.2%
- amp chassis: 4-3/8"W x 2-7/8"H (with tube) x 9-1/2"D
- power supply chassis: 4-3/8"W x 2-1/16"H x 9-1/2"D
- warranty: 1 year
- Our 60-day money-back guarantee
HiFiMAN EF5 Reviews
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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.
- Vacuum Tube: RCA Clear Top 12AU7
- OP-amp: JRC5532 OPA275
- 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
- EF-5 Headphone Amp:
- Height=2.25" (2.875" w/tube)
- DY-1 Power Supply:
- EF-5 Headphone Amp:
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1 question already asked
I would connect it to any fixed(not controlled by pre amp volume control) line out. There are no cables included. Any quality rca patch cable will work. [ Mike Mar 10, 2015 ]
No, you will need your own cables. You just hook them up the same way as you would a regular amp. [ Donald Mar 10, 2015 ]