7Hz Eternal IEM Review: Not Eternal

That 7Hz Timeless was one of the unexpected surprises of the last year. It was one of the first planar magnetic IEMs to actually be released with great tuning, and it remains one of our favorites to this day. To celebrate its 10th anniversary, 7Hz has introduced its newest IEM, the Eternal. With a similar circular design but flanked by gorgeous sapphire crystal faceplates, it features large and beefy 14.5mm dynamic drivers. Can it do for dynamic driver IEMs what the Timeless did for planars? Join us as we find out!


  • Current price: $249 (Amazon)
  • Resistance: 30 ohms
  • Sound pressure level: 109 dB/1 kHz
  • Frequency response range: 10-20000Hz
  • Distortion: <0.2%/1kHz
  • Driver: 14.5mm voice coil
  • Product weight: about 6g each earbud
  • Connection: MMCX

7Hz Eternal – First impressions and key features

The 7Hz Timeless have become a cult hit. Wasting no time, 7Hz releases the Eternal hoping to continue this trend of success. Where the Timeless featured a planar magnetic driver, the Eternal uses a single 14.5mm liquid crystal polymer dynamic. This has an immediate impact on tone and timbre, but as the resurgence of individual DD IEMs over the past year has shown us, that’s hardly a bad thing.


The headphones follow the same circular design sensibility as the Timeless, but are much more visually interesting. It features an all-aluminum shell (great for durability), but where its predecessor had plain matte black faceplates, the Eternal uses sapphire crystal. Underneath is an apparently dynamic driver, which is only used for optics. The headphones are also burgundy in color and tend towards a reddish brown.


In the box you will find a matching cable and a travel bag. The case is also made of aluminum and is quite large. It’s clearly not meant to be slipped into a pocket, but can be thrown into a pocket where it stays closed thanks to a strong magnetic clasp. Also included in the box is a selection of silicone eartips in various sizes and hardnesses.

7Hz Eternal – fit and comfort

The 7Hz Eternal is comfortable, but only if you choose the appropriate peaks. Despite the large circular exteriors, the inner portion of the earbud is contoured to fit the contours of your ear, allowing it to sit securely in the ear canal and rest in the concha. If you have smaller ears, however, it’s still possible for the outer circles to make contact, which could be uncomfortable for some users. I haven’t experienced this and have found them easy to wear during longer listening sessions.

7Hz Eternal – listening impressions

All listening was done using a mix of the Xduoo XD-05 Plus and the iFi Go Blu. Sources were Spotify in very high audio quality and high-resolution local files.


Bass: The Eternal’s low end is an improvement over the Timeless. Thanks to its large dynamic driver, bass notes have ample body and detail. They lack some of the slam of the Timeless and other single DD-IEMs, but pack enough punch to give songs like Ed Sheeran’s Overpass graffiti blow. Bass and sub-bass were accentuated, but not overly so. The bass contributes to a greater sense of balance that these IEMs deliver, but I enjoyed the added body emphasis of the songs and games I listened to.


In the middle: Mids are very neutral on the Eternal. This has the effect of making singers sound more relaxed. Instruments come through clean, but distorted guitars sometimes take on an odd fringe quality, like the Eternal is pulling more dirt out of the effect (Coheed and Cambria’s dark side of me is a perfect example of this). I would have liked the mids to be a little more accentuated and worked out a little more detail in that register.

Triple: Highs on this set are not very impressive. They don’t add much shine and air to the set while still making hi-hats and cymbals sound sizzling. After 30-40 minutes of listening I have to pause when the track or game hits the right notes to produce this effect. As a fan of heavier, guitar-heavy music, I listen to them often, which caused me to change my listening habits during testing.


Soundstage/Imaging: Soundstage and imaging on the Eternal is in line with expectations for a $249 IEM. Instrument and source placement is easy, but the head stage is fairly limited. It’s uncompressed, but doesn’t surprise you with sounds that seem to come from outside your head. Because of this, I wouldn’t pick these with gaming in mind, even with Dolby Atmos enabled.


Final Thoughts

The 7Hz Eternal isn’t a bad set, but at $249 it’s not the best choice. The issues I’ve found with tuning can be fixed with EQ, but at the current price point it just doesn’t make sense to pick it up. For $60 less that Moondrop KATO offers a similar single dynamic driver setup with better tuning out of the box. If you don’t mind making some tweaks, they can sound pretty good, but if you’re not in love with their unique aesthetic, it’s better to look elsewhere.

The product described in this article was provided by the manufacturer for evaluation purposes. Articles may contain affiliate links from which we may earn a small commission to help support the site. Authors do not earn affiliate earnings or commissions. 7Hz Eternal IEM Review: Not Eternal

Fry Electronics Team

Fry is an automatic aggregator of the all world’s media. In each content, the hyperlink to the primary source is specified. All trademarks belong to their rightful owners, all materials to their authors. If you are the owner of the content and do not want us to publish your materials, please contact us by email – The content will be deleted within 24 hours.

Related Articles

Back to top button