HiFiMAN EF2A Headphone Amp: Style & Power
Headphone amps are one of those things that you may not realize you need but once you start using it, you can’t
imagine life without one. If your computer and desktop speakers or headphones are part of your music listening
arsenal, and you spend even a fair amount of time listening through them, you should definitely consider a
headphone amp. As the quality of your headphones or speakers increase, the more you should consider an amp to
let you hear their full potential. Plugging your headphones directly into the headphone jack on your computer
certainly gives good results in most cases. However, you are likely limited in power and volume and could benefit
from a stronger signal with better clarity, dynamics and resolution. For me, the power and volume boost is reason
enough to use an amp. I toggle between using headphones and desktop speakers while at my computer and am
always craving more volume without sacrificing sound quality. The HiFiMAN EF2A gives me the punch and boost I
need with the added benefit of making my headphones sound a lot better. The icing on the cake? The amp is both
affordable and extremely stylish.
The HiFiMAN is a compact, desktop amp that has a gorgeous look with exposed vacuum tubes and a brushed
aluminum case. An acrylic top panel lets you see the guts of the device. It’s a pretty compelling package that you will
want to show off on your desk. When powered on, the vacuum tubes glow a warm and appealing orange color. There
are two inputs on the back: USB input for direct connection to your computer and RCA inputs allowing for connection
to an audio device such as a CD player. On the front, there’s a rotary volume dial, ¼” headphone jack and toggle
switch allowing you to change source from line to USB. Not just an amp, the HiFiMAN EF2A is also a DAC (Digital to
Analog Converter) with legendary and well known Burr-Brown PCM2702E chip affording not just more power: but
better sound. An external AC power supply is needed.
You can connect both an audio device such as a CD player or anything else with standard Left-and-Right RCA cables
and your computer’s USB output simultaneously. A push button on front lets you toggle between which device you
want to listen to. Once connected, simply power the amp on and use the rotary dial to adjust volume. The headphone
jack is 1/4” so you’ll need an adapter if using headphones with a mini-plug. While the amp is packaged with a 5’ USB
cable, the headphone adapter is not included. Drivers are automatically installed and there’s really nothing to setup:
pure plug and play.
If you’ve never used an amp and just connected your headphones directly to your computer’s headphone jack, you
are in for quite a surprise. You’ll get a TON more power and output and will be able to really open up your desktop
speakers or headphones and drive at a much higher volume. Clear, pure sound is not often the hallmark of
headphones utilized at their highest volume when simply using your computer’s built-in soundcard. I often had to
back down the volume on my headphones because of distortion when I wanted full volume such as when streaming
concerts. Unfortunately, that would not give me the volume that I craved. With the EF2A, volume and clarity go hand
in hand. It’s unlikely you’ll often need to dial the volume knob past the noon or 1:00 p.m. position. Dialing the
volume all the way to right will likely give you way more volume than you need in almost all cases. Frankly, with most
of my headphones that I tested the amp with, great volume was had at the 8 or 9 o’clock position.
Barring the tremendous volume and power boost, the EF2A is equally impressive when considering the sound quality
and DAC components. The biggest difference I found was the clarity of the lows. Rather than simply a booming low
end and muddy bass, the EF2A gives great definition and clarity in those lows. The sound overall is lively and warm
with some pretty striking highs. There’s really a nice balance without anything being over emphasized and music
seems very natural with a wide open feel to it. Even when listening to FLACs and other high quality audio files from
my computer without a DAC - they can sound like lower bitrate MP3s. The EF2A really gives you the full benefit of
lossless files and more intricate music: you’ll get great instrumental separation, a nice wide sound stage and much
more depth. In short, your music will simply sound better. But keep in mind, the EF2A only supports 16-bit files.
Those downloading and listening to 24-bit files would likely have little interest in an entry-level amp/dac regardless.
Another nice benefit is the silence during quiet passages. I encountered no interference or buzzing as is often
common with internal sound cards. Perhaps not a big deal for a gross majority of music listening but can make a big
difference with some music and certain passages.
Build Quality & Size
Beside the compelling design aesthetic, there is a lot to like about this amp. Everything seems solid and well made.
The volume dial scrolls smoothly, the headphone jack seems particularly well built with a solid feel that grips the
plug nicely. It should withstand a lifetime of plugging in and out. The power switch and source button both operate
very well also. I particularly like the design of the tubes that come out of the acrylic top. Should one ever blow, not
sure how likely that is or not, the replacement is as simple as screwing in a new light bulb. No tools needed. The
form factor is also a great size at roughly 5.5” x 3.5” x 2” and enough weight to sit firmly on your desktop without
taking up too much space.
This is a great sounding DAC and quite capable headphone amp that will really boost not only your volume but also
the clarity and detail of your music. It has a striking design and will definitely fetch you some nice compliments
sitting on your desk. It performed great with a variety of different headphones and at $169 is likely about as cheap
as you can get for performance this good. Like all audio products, you can spend a ton more and get much better
results, but for those that want great results at a reasonable price-point the HiFiMAN EF2A is hard to beat.
PS: I’ve reviewed a portable HiFiMAN DAC in the past and simply loved the results of that too. This company, founded
by Dr. Fang Bian in 2007, is gaining quite a reputation for high quality audio products. Keep an eye out on
Technology Jam for a review of some of their headphones as well.
Manufacturer Website: Hifiman.com
Suggested Retail: $169
Technology Jam Highly Recommended
Written By: Parker Harrington