The HiFiMan EF500 is a balanced R2R DAC with a built-in headphone amplifier, featuring an original vertical design and equipped with streaming functionality.
HiFiMan Electronics is a Chinese company founded in 2007 by Dr. Fang Bian. HiFiMan gained widespread popularity with its line of advanced planar magnetic headphones, which have won numerous awards in recent years and are considered among the best in their respective price ranges. In addition to headphones, HiFiMan produces other high-end audio electronics: DACs, headphone amplifiers, and portable music players. However, for many years, its lineup of reasonably priced desktop headphone amplifiers was limited to the EF6 model, specifically designed for the HE-6 headphones and priced at around $1600—not exactly cheap. Things changed completely at the end of 2022, when HiFiMan released the EF400, a powerful and high-performing headphone amplifier with an integrated R2R DAC, priced at around €600 and now often available for just over €500. The EF400 was highly successful, leading HiFiMan to expand its amplifier range with a more powerful and flexible flagship, the EF600, and more recently the EF500 and EF499 models, both more affordable and equipped with network connectivity.
The EF500 borrows many concepts from the EF600, starting with the “tower” design, implementing them in a way that keeps costs down while still delivering excellent musical performance.
As is customary for HiFiMan DACs, the EF500 performs digital-to-analog conversion using an R-2R DAC. This technology uses a carefully designed resistor ladder network, generally controlled by FPGA units, to perform the conversion between digital and analog signals. According to enthusiasts, when well implemented, this solution delivers a richer, more natural, and spatially defined sound compared to converters using different technologies. However, the need for highly precise electronic components often makes DACs of this type quite expensive. The EF500 uses a high-performance R2R DAC called Himalaya LE, which is an evolution of the original Himalaya found in the EF400 and aims to partially reduce costs without sacrificing performance.
The amplification section delivers an impressive output of 4.5 W at 32 ohms via the balanced output (1.32 W via the unbalanced output). In addition to USB input, the EF500 also features a coaxial input and an Ethernet port for streaming functionality. For just over €500, the EF500 offers a high-quality R2R DAC, a very powerful headphone amplifier, and network streaming features. It is difficult to find competing devices offering the same features in this price range.
Like almost all HiFiMan products, the EF500 comes in a large, no-frills cardboard box containing only the amplifier and a standard power cable. It has a solid and minimalist appearance, distinguished by its tall and slim chassis. This solution, first used in the larger EF600, allows for better heat dissipation and reduces horizontal desk space usage. According to HiFiMan, the EF500 can also be used as a headphone stand, freeing up additional desk space. We have already tested this solution with the EF600 and are not entirely convinced: the EF500, just like the EF600, starts to warm up after a few minutes of use, and headphones placed on top will also heat up—something that may not be pleasant, especially during hot weather like the period in which we are writing this article.
The bottom of the EF500: screw-on base, voltage selector
The “tower” layout, despite its clear advantages, can be problematic in some situations: when used near a desktop PC, it is impossible to place the EF500 in the classic position behind the monitor, as the volume knob would be hidden by the screen. Placing it in front of the monitor blocks the view entirely. The only option is to position it to the side, and if the monitor is large—or worse, if multiple displays are used—the EF500 may end up quite far away and inconvenient to use. Consequently, there is also the risk of needing longer cables than usual.
On the rear panel, we find the power socket and power switch, two balanced XLR outputs, and two unbalanced RCA outputs. The placement of the power switch on the rear—like other recently reviewed HiFiMan amplifiers—is clearly inconvenient. Available inputs include USB-B and USB-C (not usable simultaneously and not selectable via any switch). There is also a coaxial digital input to which devices such as a CD player can be connected. Finally, there is an Ethernet port for media streaming.
The knob for gain adjustment
The front panel is simple, with two headphone outputs at the bottom, a central volume knob, and a settings knob at the top. The volume knob is somewhat rough but precise. A smaller knob on the top controls gain and the digital conversion mode between High Gain NOS / High Gain OS / Low Gain NOS / Low Gain OS. NOS stands for “No OverSampling”: in this mode, the signal is converted more directly, without altering its frequency and with less use of complex audio filters.
Whether oversampling is preferable in A/D conversion is a complex and long-debated topic. In the case of the EF500, the same considerations apply as with the EF400: NOS mode appears more defined and less “veiled,” while OS mode is characterized by greater warmth in the low frequencies. The choice between the two will likely depend on the headphones used and personal preferences.
The EF500 has no input selector on the front: to switch between USB and coaxial input, a toggle on the rear must be used, while the Ethernet connection appears to deactivate automatically when a signal is detected on the USB port. The system works, but it is clearly inconvenient and impractical.
The streaming features of the EF500 allow playback from online platforms such as Spotify, Roon, Spotify, Apple Music, Sony Select, and many others. It is also possible to play a locally stored music library (for example on a NAS) via Ethernet using applications such as Synology Audio Station. We were unable to test these network features, but they are certainly a welcome addition given the increasing number of users who rely on them daily.
We tested the EF500 with a wide variety of headphones, including some of HiFiMan’s most famous planar magnetic models: Sundara, Edition XS, HE6v2 SE. To evaluate its behavior with high-sensitivity, low-impedance headphones, we also tested it with Grado SR80E.
DAC operating diagram
The EF500 requires many hours of burn-in: at first use it sounds thin and flat, and needs some time to reveal its true character, which is warm and musical. The EF500 is clearly designed as an ideal companion for mid-range HiFiMan headphones, and indeed it brings out the best in them: it sounds dynamic, musical, and never fatiguing, and its generally warm character adds body to these headphones. The power is more than sufficient for all the headphones we tested; only with the HE6v2 SE does the EF500 show some limitations—in that case, we recommend the EF600 or other equally powerful and high-performing amplifiers. The EF400 also delivered excellent results with Grado headphones, providing a particularly balanced sound; however, with these highly efficient headphones, the usable volume range is very limited, which can be an issue especially if you prefer low-volume listening.
Having also tested the other HiFiMan amplifiers under €1000, we can now make a brief comparison.
The most affordable DAC/headphone amplifier in the HiFiMan catalog is currently the EF499. Identical in shape and layout to the EF500, it differs by using a Philips-derived R-2R DAC, which is cheaper but less performant than the HiFiMan Himalaya. Otherwise, it retains all the EF500’s features and is currently sold for around €350. At this price, it is quite impressive in terms of functionality and particularly suitable for those who rely on streaming content.
The EF500 currently costs around €540; the price difference is therefore significant, but if you have good headphones, it is probably worth it: the EF500’s Himalaya DAC is certainly superior and delivers a more detailed and musical sound. If you do not need streaming features and do not appreciate the vertical design of other HiFiMan headphone amplifiers, for a slightly higher price you can purchase the EF400—now a classic and still absolutely valid in terms of musical performance. For those who can spend around €700, the EF600 offers the best in this HiFiMan product line in terms of power, sound performance, and flexibility.
In summary, the EF500 is a DAC/headphone amplifier combo with distinctive features, positioned in a very crowded market segment (around €500). However, the use of an R-2R DAC, a powerful amplification stage, and streaming capabilities clearly set it apart from competitors. For those looking for an excellent DAC with a warm and musical sound, capable of driving planar magnetic or high-impedance headphones—and who may want to take advantage of modern music streaming—the EF500 is highly recommended without hesitation.
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