HIFIMAN HE-R9 Review: Booming Bass Closed-Back Headphone

Disclaimer: I received this product in exchange for my honest review. The Metalverse is an independent website, and all opinions expressed are our own with no monetary incentive. We thank the team at HIFIMAN for giving us this opportunity.

HIFIMAN

Founded in 2007 by Dr. Fang Bian in New York, HIFIMAN has built its reputation on pushing the boundaries of planar magnetic technology. The company revolutionized portable audio with the legendary HM-801 digital audio player and has consistently delivered quality headphones that audiophiles trust.

Known for their open-back planar magnetic headphones like the Sundara, HE400SE, and the flagship Susvara, HIFIMAN surprised the audio community when they ventured into dynamic driver territory. The HE-R9 represents the company's continued exploration beyond their comfort zone.

HIFIMAN HE-R9

The HE-R9 is a full-sized, closed-back dynamic headphone that launched in early 2022 with an original price tag of $599 (now significantly reduced to $79).

The HE-R9 has a distinctive elongated earcup shape with a glossy crimson finish. Unlike the brand's more common planar offerings, the HE-R9 features a dynamic driver, showing HIFIMAN's willingness to experiment.

Dr. Bian's used his background in nano-materials research shines to create the HE-R9's proprietary Topology Diaphragm technology, which applies nanoparticle coatings to create unique acoustic properties. While HIFIMAN has earned countless accolades for their planar designs, this dynamic driver headphone shows the company isn't afraid to take risks.

One nice feature to note is that if you have the HIFIMAN Bluemini R2R (which we received with our Deva Pro), it's actually compatible with the HE-R9 too–taking it from a wired headphone to a fully wireless headset that is compatible via Bluetooth with your mobile device or any other BT device.

The HE-R9 targets music lovers who prioritize fun, engaging sound over analytical precision.

Build Quality and Design

Picking up the HE-R9 for the first time, they are incredibly light at just 328 grams. The leather-wrapped headband features memory foam padding and a steel skeleton with impressive flex. Comfort is genuinely exceptional here—the padded headband distributes weight evenly, and the plush hybrid earpads (leather exterior with fabric mesh facing) gently encircle your ears without creating hotspots that cause pressure.

But here's the catch: that featherweight construction comes from a lot of plastic use. Those massive, eye-catching red earcups are molded plastic with a glossy finish that looks striking but feels somewhat hollow. However, HIFIMAN does claim that this design, featuring the elongated outer chamber, optimally accommodates the driver's back wave.

The included cable is HIFIMAN's standard soft, rubberized affair—functional but uninspiring. It terminates with dual 3.5mm connectors (one per earcup) and includes a 6.3mm adapter. The cable's right-angle plug is practical for portable use, though some audiophiles are likely to swap it for aftermarket options.

Sound Quality

The HE-R9's low-end is unquestionably its defining characteristic. It isn't subtle audiophile bass—it's a powerful rumbling impact that makes electronic music, hip-hop, and modern music absolutely boom. The sub-bass extends impressively low with tangible rumble, while mid-bass delivers serious punch that you can feel vibrating through the earpads.

In comparison to all other HIFIMAN Headphones we've tried, the HE-R9 is by far the most colorful and bass-driven. Following more of a V-shape sound signature, lows are clearly emphasized, and a slight dip in the low mids helps to lessen bass bleed.

While the tuning of the HE-R9 is exciting and particularly fun for a lot of modern genres, it does come with the tradeoff that when listening to jazz or classical music, you are likely to notice some slight muddiness. The slight bleed into the midrange adds warmth, but overall will sacrifice some clarity. The bass execution errs more on the side of color and emotional engagement rather than tightness and precision.

The HE-R9's mids are enveloped in a smoothness that makes long listening sessions free from fatigue. While the mids are a little relaxed, vocals still maintain a solid presence with male vocals gaining richness and body, while female vocals may sound slightly more distant but remain pleasant.

The faint veil over mids won't bother most listeners and can actually add to the character and color of the HE-R9 but audiophiles looking for neutral reference monitors could find the signature distracting.

Treble response seems to be rolled off, creating a darker presentation that is very forgiving against sibilant tracks. Although high frequencies are somewhat muted, they still manage to cut through the juicy bass, but won't reveal as much micro-detail as a more neutral-tuned headset.

The soundstage has respectable width and height, although some depth and airiness may be lost from the slightly recessed treble.

Comfort & Isolation

HIFIMAN explicitly designed the HE-R9 for extended listening sessions, and comfort truly excels here. The generous memory foam padding, lightweight construction, and light clamping force combine perfectly for lasting comfort.

The fabric mesh on the ear-facing side of the pads prevents excessive heat buildup compared to all-leather designs, though summer listening still gets warm. The pads are deep enough to accommodate most ear sizes without making contact, maintaining that "floating" feeling even hours later.

Isolation for closed-back headphones will be better, although stacked up against other closed-backs, I would say the isolation on the HE-R9 is about average. The clamp on the HE-R9 is relatively light and is very comfortable while stationary, but will have some wiggle when in motion.

The low impedance (60Ω) and high sensitivity (100dB) suggest easy driveability, and they do get loud from smartphones. However, they scale noticeably with better amplification. Pairing with a dedicated headphone amp improves bass control, midrange clarity, and overall dynamics.

How the HE-R9 Compares to Other HIFIMAN Headphones

vs. HIFIMAN Sundara Closed-Back ($399)

The Sundara Closed-Back sits just $30 above the HE-R9 at regular pricing but employs planar magnetic drivers with Stealth Magnet technology. Build quality feels superior thanks to beechwood earcups that add visual appeal and structural rigidity.

Sound-wise, the Sundara Closed offers better technical performance across the board—improved detail retrieval, tighter bass control, and more neutral tuning. However, it still leans warm compared to open-back planars, just not as dramatically as the HE-R9. The Sundara's bass is tighter and more controlled, making it better for diverse genres.

The HE-R9 delivers a more colorful and fun bass impact. The Sundara Closed is the more technical and versatile option; the HE-R9 is the party animal. If you primarily listen to bass-heavy genres and prioritize engagement over accuracy, the HE-R9 holds its own despite the Sundara's technical advantages.

vs. HIFIMAN Deva Pro ($329)

The Deva Pro represents HIFIMAN's open-back planar offering at a similar price point. It includes the Bluemini adapter standard and delivers that signature planar sound: balanced, detailed, with excellent speed and transient response.

The Deva Pro sounds more neutral and technically proficient than the HE-R9, with better instrument separation and a more expansive soundstage (as expected from open-backs). However, bass lacks the HE-R9's physical impact—planar bass is fast and controlled, but doesn't have that dynamic driver slam.

vs. HIFIMAN HE400SE ($169)

The HE400SE is HIFIMAN's budget planar offering and an incredible value. It delivers neutral, well-balanced sound with excellent detail for the money. It's open-back, requiring more amplification power than the HE-R9.

Sound quality comparison again favors the HE400SE for listeners seeking accuracy. It's airier, more detailed, and better balanced. The HE-R9 counters with warmer tonality, more bass quantity, easier driveability, and closed-back isolation.

Our Verdict

The HIFIMAN HE-R9 is an unabashedly colored headphone that prioritizes musical enjoyment over accuracy. At the current $79 price point, it offers a good value for listeners who connect with its warm, bass-forward signature.

These headphones excel with electronic music, hip-hop, modern pop, and rock genres that benefit from impactful low-end and smooth, non-fatiguing tonality. They're also perfect for movie watching, with the low end making cinematic moments even more dramatic.

However, they're not versatile all-rounders. Classical music, acoustic jazz, and audiophile recordings reveal the HE-R9's limitations in transparency and detail.

The lightweight build quality feels questionable at the original $599 asking price, but it is very good for $79.

If you're seeking HIFIMAN's typical planar sound—neutral, detailed, fast—stick with the Sundara Closed-Back, HE400SE, or Deva Pro. But if you want a fun, bass-heavy closed-back that punches way above its current price for specific genres, the HE-R9 delivers that guilty pleasure in spades.

These headphones won't win over purists, and that's okay. They're designed for music lovers who just want to get lost in their favorite tracks without worrying about perfect tonal balance. For that purpose, mission accomplished.

Technical Specifications Summary

• Driver: Dynamic with Topology Diaphragm technology
• Design: Closed-back circumaural
• Frequency Response: 15Hz - 35kHz
• Impedance: 60Ω
• Sensitivity: 100dB
• Weight: 328g (11.6oz)
• Cable: Detachable dual 3.5mm TRS, 1.5m length, 90-degree plug
• Accessories: 6.3mm adapter
• Optional: Bluemini R2R wireless adapter (Bluetooth 5.0, LDAC/aptX-HD, 8hr battery, 230mW output)
• Warranty: 1 year (extendable to 15 months with registration)

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