Welcome back to another edition of Golden Ears. In this week’s column, we’re taking a look at the HIFIMAN EF600, a powerful desktop DAC/amp that replaces the sound from your PC and doubles as a headphone stand. It sounds amazing thanks to its R2R Hymalaya Pro ladder DAC and fine-tuned amplification system. And with 5.12 watts of power per channel (10 watts total), it has enough output to drive just about any pair of headphones and even some full-size speakers. At $649, it’s definitely Golden Ears territory but it’s also unique, and uniquely appealing, at this price.
Specifications
- Current Price: $649-799 (Amazon, HIFIMAN, Apos Audio)
- Key Features
- Himalaya Pro R2R DAC
- Up to 5 watts per channel
- Designed to act as a headphone stand
- aptX, aptX HD, LDAC support
- Balanced, single-ended, RCA, and XLR outputs
- Outputs: 6.3mm single-ended, XLR four-pin balanced, dual (L/R) XLR three-pin full balanced line outputs
- Rear inputs: RCA, USB-B, and USB-C source connectors
- Signal-to-noise ratio: 118dB (weighted)
- Channel separation: 131+/-3dB
- THD+N (line out): 0.0014% (-8dB)
- Maximum power output: 5.12 Watts per channel @32 ohm balanced/1.8 Watts per channel @32 ohm
- Dimensions: 104mm x 135mm (top), 104mm x 165mm (bottom), 283mm (height)
A Quick Re-introduction to Golden Ears
Welcome back to Golden Ears! This is our semi-regular column dedicated to the world of high-end audio. In this series, we look at premium audio products that all promise a next-level listening experience. But what exactly do you get when you spend a little, or sometimes a lot, more? That’s what we aim to discover, helping you to find out just what’s worth investing in to upgrade your listening experience for music and gaming alike.
For this article in particular, we’re looking at the HIFIMAN EF600, a hybrid DAC and amplifier with top-tier audio tech in a unique form factor. It currently retails for $649 to $799 depending on where you buy it but delivers a ton of power and outstanding sonics. At this price, it exists in the upper-range of the personal audio market, beyond typical consumer pricing and well into enthusiast territory. As such, discussions of value are more subjective than ever. For many listeners, that pricing is simply out of reach, and no matter how good they are, they will seem like a terrible value. For others, passionate audiophiles with plentiful expendable income who consider audio their primary hobby, may have a different opinion.For products like this, ideas of value are very subjective; one person’s steal might be another’s exorbitance, so we’ll largely be leaving that to the side today.
On the topic of scoring, it’s important to note a couple of things. First, while we wish we didn’t have to do it, it’s a reality in today’s search-driven publication space. Second, when dealing with “golden ears” caliber products that often cost great deals of money, we expect these products to be at least Good (7) but hopefully Great (8), Amazing (9), or even Masterpiece (10) level. Though there are certainly products tha aren’t very good at every price range, a quick review of web publications shows that the score range is usually a bit tighter with these next-level listening products. Fittingly so — they should sound great!
Given that expectedly tighter score range, it’s more important than ever to explore the nuances of what sets these products apart. What is their goal? Who are they for? How are they built? What are the intricacies of their listening experience? All of these things matter more and the number matters less. We are always going to be honest and forthright in all of our content, but take the time to hear the story each product is trying to tell, and you’ll understand it that much better.
Thanks for joining us again, and enjoy the article!
HIFIMAN EF600 - Design and Highlights
The HIFIMAN EF600 is a unique product. It’s a hybrid DAC and amplifier that is primarily designed for headphones but has enough output for many full-size speakers. It stands tall and looks regal with its aluminum front and rear plates but has a plastic center that dips and contours. Measuring 283mm (11 inches) tall, it makes a statement.
This design is about more than just looks, however. The EF600 is designed to be a headphone stand as well, creating the perfect place to keep your premium headphones or favorite gaming headset when they’re not in use. A headphones stand is a simple thing (that can get surprisingly expensive depending on what you’re looking for), but combining both into a single unit saves desk space and winds up looking a lot better than most standalone stands. The vertical orientation also allows heat to escape out the top instead of venting from the rear or directly on your desk.
The front of the EF600 is simple yet refined. A balanced XLR and 6.35mm single-ended jack are placed on the bottom. Just below the center of the face is a large rectangular volume dial. The top half of the unit features left and right input buttons and two columns of indicator lights. Along the left, are NOS (no oversampling) indicator lights for its low and high gain modes and the four potential audio inputs: USB/Coaxial, Bluetooth, RCA, and Balanced In.
Around the back of the unit, we have the physical connections for those indicators. USB and Coaxial inputs are positioned on the top, in line with a Bluetooth antenna that extends above the metal faceplates for better reception. Descending vertically we then have left and right XLR input jacks with integrated locks, RCA in and out jacks, and two XLR balanced outputs. The AC port and power switch are positioned along the bottom.
Between these plates, the center contour is made of black plastic but doesn’t feel cheap. In fact, the unit has good heft and a premium feel overall. The contour is recessed but not overly so. You won’t need to worry about the bottom of your cans resting on your desk. It’s also wide enough for any pair of headphones that I’ve seen, which allows it to work well for its intended purpose.
Internally, the EF600 uses HIFIMAN’s Hymalaya R2R ladder DAC, which we’ve seen on a number of the company’s other products at this point. Unlike a Sigma-Delta DAC, a ladder DAC uses a chain of resistors to convert digital ones and zeros into something your headphones can interpret. HIFIMAN isn’t the first company to apply this technology but its implementation is unique and does away with some of the shortcomings usually associated with it: namely, higher levels of electrical noise, power draw, and distortion.
If you want to talk numbers, HIFIMAN is ready to do that. It has an impressive signal-to-noise ratio of 118dB and total harmonic distortion of only .0014% at -8dB. Channel separation is rated at 131±3dB. It’s also able to decode audio up to 24-bit/768kHz, though there’s no support for MQA audio within this design.
HIFIMAN was able to develop the EF600 with two discrete channels, including separate amp and DAC components for each. Its rated power output is 5.12-watts but that’s per channel, meaning that the total output is upwards of 10 watts. Because of how it’s designed, this is clean, silent power delivery whether you’re listening on very insensitive headphones or even IEMs (low and high gain modes for the win).
Finally, we have to share the amp's wireless capabilities. HIFIMAN has invested a lot of time and effort into its wireless solutions over the last few years and clearly sees it as a powerful force in the future of high-end audio. To that end, the EF600 supports Bluetooth connectivity with support for high-resolution codecs. Altogether, it supports LDAC, aptX HD, aptX, AAC, and SBC. While I would love to see aptX Adaptive on a device like this, LDAC remains a very good option for high-bandwidth near-wired-quality listening and since you won't be moving around very much while plugged in, it's steady and reliable throughout.
HIFIMAN EF600 - Listening Impressions
This type of high-end, high-power design is targeted at audiophiles, but, make no mistake, upgrading from integrated audio to something like this is a noticeable improvement akin to jumping from SD to 4K in one fell swoop. Whether you’re listening to music, gaming, or even watching movies, it’s a noticeable upgrade that you won’t want to come back from.
I tested the unit at my main PC for several weeks using multiple headphones and IEMs. Everything from the demanding HE-1000 V2 and Fiio FT3 to the Letshuoer S15 and Campfire Audio Andromeda Emerald Sea. Across the board, it delivers excellent results and pushed each set I paired it with to its potential.
The EF600 has a very rich sound that presents music and games with a full body and plenty of detail. The resolution of the DAC and its dual-channel design allows tiny details to come forth and stand out. Whether it was the headroom of the amplifier, the technical capability of the DAC chips, or a little bit of both, I found certain sets to be even more resolving (like the S15) than they are on integrated audio or even my RODE Procaster Duo audio interface.
The true answer is, of course, that it’s both. The DAC handles the conversion and really allows your headphones and IEMs to perform their best. The amplifier ensures that you have enough clean power that you have ample volume headroom and voltage for the drivers to reach their potential without rising to ear-splitting levels.
This combination also highlights exactly why devices like this have such appeal compared to integrated audio or even smaller portable DACs. The design centers on audio reproduction and nothing else. The engineers choose every component, run every trace, work and rework and rework, until the final product has a particular sonic signature or is invisibly neutral. Here, the level of silence in the background allows it to have exceptional dynamic range, creating the perception of enhanced detail. Electrical noise from a crowded motherboard, even at levels silent enough that you don’t notice in normal use, isn’t present here. When you go back to that integrated audio, it immediately sounds less clear in comparison.
There is one interesting quality here worth remarking on, it’s oversampling. The DAC is able to send audio in either over-sampled or non-oversampled (NOS) format. This is related to how the audio is converted to analog and whether it applies digital filters to the audio being reproduced. The NOS options on the EF600 eschew filtering for a more organic, analog sound.
In practice, the difference between these modes is subtle. I find the NOS options to be slightly smoother, though I admit that I’m not entirely sure if it’s placebo. Without a fellow audiophile nearby to sanity check me, I really can’t say for sure. It’s an option, and one you might enjoy, but its impact is very minor overall.
Final Thoughts
The HIFIMAN EF600 is a great DAC/amp hybrid and could be an asset to any desktop. In an ever more crowded market, its form factor is one of its biggest assets, yet it could also be the very thing that puts it out of the running for some listeners. If you’re looking for a low profile option that can slide under a monitor or do anything other than stand out on a desktop, this isn’t it. I would also be remiss for not mentioning the lack of a 4.4mm balanced output, which makes it incompatible with balanced IEMs without a special adapter.
Still, it offers a solid value. HIFIMAN’s Hymalaya R2R DAC is excellent. The detail it offers is very, very good and its power delivery is clean, quiet, and offers tons of headroom. It’s expensive, yes, but is competitive in the price bracket it competes in. And, just as importantly at this price, it feels expensive. The fit and finish are great.
With that in mind, this DAC, while not a fit for every listener, will still make for a very good choice for quite a few and will push just about anything connected to it to its full potential. It’s a pleasure.
The product described in this article was provided by the manufacturer for evaluation purposes. Some articles may contain affiliate links and purchases made through this will result in a small commission for the site. Commissions are not directed to the author or related to compensation in any way.
