HIFIMAN, founded by Dr. Fang Bian in 2007, has firmly established itself as a visionary leader in the world of hi-fi. They pursue perfection with every new generation, the company is renowned for pushing the boundaries of audio technology. Specialized in state-of-the-art planar magnetic headphones, digital audio players and amplifiers, HIFIMAN combines innovation with craftsmanship.

At the heart of HIFIMAN’s vision lies a commitment to deliver pristine sound reproduction that captures every nuance and emotion of music. Dr. Bian and his team believe that exceptional audio is not merely about technical specifications but even more about creating deep, meaningful connections between listeners and music. Each new product reflects this philosophy.

In this review, we dive into HIFIMAN’s HE-R9, already a while on the market, exploring its build quality and most importantly, its performance. The HE-R9 is not a planar what I am used to listen to, so I am curious how it performs.

Hifiman asked my opinion so will give these a decent testrun.

Test equipment:
– Iphone 16 pro
– Chord Mojo 2 + Poly
– Eversolo A8 + upgraded LHY LPS
– Chord TT2 + Mscaler, both upgraded LPS

Test Tracks
– Dave Brubeck – Take Five
– Patrica Barber – Regular Pleasures
– Diana Krall – Temptation
– Bill Evans – Waltz for Debby
– Art Blakey & The Jazz Messengers – Moanin

The HE-R9, is rich featured, by supplying a 3.5 cable and usb&bluetooth dac

First Impressions
When unboxing the HIFIMAN HE-R9, it is immediately clear that this is not your average headphone. The large, dynamic cups, wrapped in a glossy red finish, quite bold. The shape the cups made me think of the legendary Sony MDR-R10 from 1988/1989, one of the first ‘real’ high-end headphones back then.

Instead of wooden cups, the cups are made of polymer with a sturdy headband, giving the headphone a decent balance between weight and robustness. The comfort is surprisingly good, thanks to the soft, leatherette earpads and the balanced clamping force. Despite the size, you can wear these for long listening sessions without discomfort. They are extremely light, very nice when traveling.

The design is clearly a continuation of the aesthetic used in their closed-back models, but the R9 adds a touch of extra flair with its unique look. While it may not appeal to everyone’s taste, it certainly makes a statement. The quality of materials feels fine for the asking price, though it’s not as premium as some of HIFIMAN’s more expensive models.

What is in the box
Inside the box, you’ll find a detachable cable that features the 3.5mm connector, if you decide to upgrade later. The stock cable is functional, though nothing extraordinary, but it gets the job done.
Besides that, there is also a R2R Hifiman Bluemini R2R mini bluetooth adapter, you can connect this unit directly to the headphone, easy when you don’t want a cable. This dongle can also be used as a direct connected usb dac. It is quite multi functional.

Bluemini R2R Bluetooth Module
The Bluemini R2R is a compact Bluetooth DAC/amp add-on specifically designed for HIFIMAN headphones that feature the TRRS balanced input, such as the HE-R9, DEVA, and DEVA Pro. What makes this module stand out is its built-in R2R (ladder) DAC, based on HIFIMAN’s proprietary “HIMALAYA” architecture. Unlike conventional delta-sigma DACs, the R2R design uses a network of precision resistors to handle digital-to-analog conversion, often praised for its smoother, more natural, and organic sound signature.

With support for high-resolution Bluetooth codecs like LDAC and aptX HD, the Bluemini R2R enables wireless playback without sacrificing too much quality. The module also doubles as a USB DAC as mentioned, making it versatile for both wireless and wired use. 

The Bluemini R2R Bluetooth module can also be used as USB-C dac 

Sound Performance
The HE-R9 delivers a sound signature centered around a rich, warm and somewhat bass-forward presentation. The lower frequencies are prominent but never sloppy. They carry good texture and depth. People who prefer a little bit more low end power, will likely enjoy the punch and authority these headphones offer. The midrange is slightly recessed but smooth nonetheless, giving vocals and instruments a relaxed and easygoing character.

Treble is laid-back, never harsh, which makes the HE-R9 very forgiving. This sound signature makes it suitable for long listening sessions without causing fatigue. However, those who prefer an analytical or very detailed sound might find it somewhat lacking in resolution and sparkle at the top end. To them I would advise, going for their amazing planar headphone range.

The soundstage is intimate, which is typical for almost all closed-back designs, but it doesn’t feel claustrophobic. Imaging is good, instrument placement is natural and easy to follow. It doesn’t reach the spaciousness of open-back headphones, but it does create a pleasant and immersive listening bubble. And let’s be honest, open-back  headphones ‘altough amazing’ is actually only usable in a calm, quiet environment.

Amplification
Without the Bluemini R2R, the HE-R9 is relatively easy to drive, working fine even from portable devices, though it does benefit from a decent amplifier.

I connected it to my Chord TT2 combo, and my small mojo2-poly… The HE-R9 Scales very nice. When powered properly, the bass tightens up and the dynamics improve noticeably. Pairing it with a neutral or brighter amplifier can also help to balance out the warm signature and open up the treble a bit more. It’s all about matching (nothing new in Hi-Fi)

This headphone has a sensitivity of 100dB and an impedance of 32 Ohms, making it relatively easy to drive. It will work fine with smartphones, dongles, or portable players, but of course, pairing it with a proper amplifier will push its performance further.

Technical Details
The HE-R9 uses a 50mm dynamic driver, different from the planar magnetic drivers that HIFIMAN is mostly known for. This dynamic driver is paired with what the company calls “Topology Diaphragm” technology. The diaphragm has a nano-coating applied in a specific pattern, which, according to HIFIMAN, helps to improve sound clarity and reduce unwanted distortions.

Bass
The HE-R9 puts a strong emphasis on the bass frequencies. The low-end is full-bodied, with a substantial presence that bass enthusiasts will likely appreciate. The sub-bass reaches deep, giving tracks that extra layer of rumble when needed. 

Mid
In the mids, the HE-R9 tends to lean towards a smoother and slightly recessed presentation. (For me personally a little too much, but I am a open-back planar fan) Vocals, both male and female, sound natural but are a bit further back in the mix compared to the bass. This gives the overall sound a laid-back character. The midrange is not the most detailed or resolving in the closed-back market, but it’s consistent and non-fatiguing, Like a good old glass of aged scotch.

Treble
The high frequencies are somewhat softened, avoiding sharpness or harshness. Not everyone likes that, but it makes for a more forgiving headphone for longer sessions, as you don’t get any piercing treble that could cause listening fatigue.
However, those who are looking for sparkly or extremely detailed treble might find it slightly rolled off.

Soundstage & Imaging
Given that it’s a closed-back design, the soundstage is naturally more intimate than that of its open-back siblings. Still, it manages to avoid sounding boxed-in. There is a pleasant sense of space, and the imaging is accurate enough to position instruments and vocals correctly within the sound field.

The HE-R9 is multi-functional (cabled, usb-dac, bluetooth) and very lightweight, so a perfect travel companion, and quite pretty too.