Fit and Comfort

There are subtle fit differences between the different silicone ear tips that come with the 7Hz Timeless, at least within the same size. It's hard to see on the camera front-on, however, since the larger exterior covers the actual section that fits into the concha and ear canal. As such, I am only showing the by default pre-installed size-M ear tip on the right ear bud inserted into an artificial ear mold. I have average-sized ears, and the ear mold above represents my own experiences well enough as a proxy. Size M silicone tips are my go-to for testing since foam tips are not included by some, as is the case here. You may want to consider getting some foam tips if the provided silicone tips don't work out well, which seal better while potentially dampening the treble response, too. The outer circular section generally won't get in the way for most people, and ends up floating above the concha itself. It's not the most comfortable set I have worn. While probably not even in my top 5–10, it is not uncomfortable to my ears, either. The angled connectors on the cable are handy in routing it nicely above and behind the ears for further support. Also note that 7Hz claims each IEM weighs 5 g, but these weigh 7 g each instead, which is still below average—as such, the mass itself is not going to cause physical fatigue, or the lack thereof. Passive isolation isn't the highest owing to the larger number of vents, but it is not a semi-open set.

Audio Performance

Audio Hardware

There are those who did see the previous 7Hz offerings being.. adapted.. from a few OEM offerings, and the big move away from a single dynamic driver to the planar setup here did not change some thoughts on this being another such product. 7Hz probably does not have its own manufacturing facility, and the use of 2-µm thick diaphragms further lends credence there. It's certainly not ultra-thin for planar drivers, no matter how hard the company wishes it so, but the working mechanism remains unchanged, with a voice coil integrated over the diaphragm and two sets of magnets on either side moving it back and forth quickly. The use of strong neodymium N52 magnets will certainly bolster the driving force, given the potentially higher magnetic flux relative to other magnets, and then we see a few more tweaks with the acoustic chamber retrofitted into the shell design itself. At this point, I am leaning towards the shell as the most unique part here, but time will show whether others will use the same driver package in other IEMs or not. Regardless, things have to come together properly, be tuned well, and have a good overall user experience. The 7Hz Timeless happens to be 14.8 Ω, which is below average and makes these even easier to drive is the 104 dB/mW sensitivity, though the company omitting the mW part drove me nuts. The 7Hz Timeless is just fine with mobile devices thus, and a portable DAC/amp will suit your needs perfectly for when you find yourself without an available 3.5 mm audio jack when on the go. If not, the shorter cable included with IEMs might be a potential handicap if connecting to a PC as the audio source.

Frequency Measurement and Listening

I will mention that I have a general preference for a warm-neutral signature with a slightly elevated bass, smooth treble range, detailed mids, and good tonal separation. I also generally prefer instrumental music over vocals, with favored genres including jazz and classical music.


Our reproducible testing methodology begins with a calibrated IEC711 audio coupler/artificial ear IEMs can feed into enough for decent isolation. The audio coupler feeds into a USB sound card, which in turn goes to a laptop that has ARTA and REW running and the earphones connected to the laptop through the sound card. I begin with an impulse measurement to test for signal fidelity, calibrate the sound card and channel output, account for floor noise, and finally test the frequency response of each channel separately. Octave smoothing is at the 1/12th setting, which nets a good balance of detail and noise not being identified as useful data. Also, the default tuning was used for testing, and no app-based settings were chosen unless specifically mentioned. Each sample of interest is tested thrice with separate mounts to account for any fit issues, and an average is taken of the three individual measurements for statistical accuracy. For IEMs, I am also using the appropriate ear mold fitted to the audio coupler for a separate test to compare how the IEMs fare when installed in a pinna geometry instead of just the audio coupler. The raw data is then exported from REW and plotted in OriginPro for easier comparison.


The IEC711 is such that you can't really compare these results with most other test setups, especially those using a head and torso simulator (HATS). The raw dB numbers are also quite contingent on the set volume, gain levels, and sensitivity of the system. What is more useful information is how the left and right channels work across the rated frequency response in the 7Hz Timeless, or at least the useful part. The left channel was separately tested from the right one, and colored differently for contrast. I did my best to ensure an identical fit for both inside the IEC711 orifice, so note how the two channels are nearly identical through the bass and mids, and then comes the part where memes about 7Hz quality control have started arising. This is all because the product is already a commercial hit owing to gushing reviews, with some people now seeing 7Hz as potentially unable to keep up with demand. The pre-order status says as much, with supply chain constraints acknowledged by the brand. The latest iteration with the metal grille mesh filter rather than the foam insert seems to have been more consistently inconsistent in its treble channel matching. That said, note that these measurements were taken after ~40 hours of testing, and while the actual graph did not change, I had to specifically listen for it to perceive the channel imbalance. In daily use, this wasn't really an issue because the actual listening experience far overshadowed it. There wasn't much of a burn-in effect either with pretty much what you get unboxed it after even 40 hours of music and a mix of white/pink noise going through the IEMs. The response with the artificial pinna in place is also quite impressive for how similar it is to the coupler itself, with a slightly darker roll-off in the upper treble there.


Let's talk about that listening experience now, shall we? I mentioned before that the previous 7Hz IEMs came and went without much consideration, and I can't speak for it since I have not listened to any of them before. But the 7Hz Timeless, whose frequency response is plotted against my personal target above taken from VSG.squig.link, is tuned really well. It's a mellow V-shape, or even U-shape tuning, which already appeals to me personally. But almost every single aspect here should resonate well with the general consumer market too, which is what has made this a product worth buying.

It would be fair to say that most of the mainstream appeal when it comes to audio is dedicated to the bass response, and most audiophiles indeed prefer an elevated bass tuning relative to a flat-line neutral response. The 7Hz Timeless provides all that and more, often to where bass heads may well be satisfied, too. It's more the elevation compared to the recessed mids that makes it deceptively punchier than what the frequency response shows, which will play well with sub-bass adhering genres, including dubstep and EDM. The bass is not bloaty in the slightest, and there's plenty of slam to add weight behind the notes. Felt distortion is minimal, which makes for detail retention to better appreciate bass guitar notes amid other music genres; say, in old school funk.

The lower mids are a touch too recessed for my liking, but this means there's no bass bleed into the mids. In practice, male vocals come off laid back and can be more backward facing than pleasant for fans of country music, for example. Baritones in operas also take a step back here, and the mids generally lack range to better appreciate instruments galore. This hurts the technical performance to an extent, with a taller than wider soundstage that won't win any technicality awards. Imaging is fairly decent though, but not a selling feature for the 7Hz Timeless, either. The transition over to the upper mids is elevated again, and female vocals do come off more forward-facing—almost in your face if you weren't expecting it. This dichotomy of male and female vocals can be somewhat jarring, but such is the power of psychoacoustics that I quickly found myself getting used to it.

It's a good thing too since the treble response is bright, although not as much as the tuning curve suggests. Part of that 8 kHz peak is accentuated by the coupler itself, but it does appear to be a case of the newer production batches making for an even brighter presence here. For treble-sensitive listeners, there is potential ringing with instrumental second and third-order harmonics, more so with the 12.5 kHz peak, where harps and piano keys share the space with cymbals and triangles. In general, I would recommend something else for orchestral and classical music anyway; the 7Hz Timeless was in multiple ways more on the "down low."

Comparisons

I decided to break my own unwritten rule about comparisons with no more than two other products in the same graph here, but only because the 7Hz Timeless is such a hot topic of discussion. First up are the other planar IEMs tested so far, including the hybrid HarmonicDyne P.D.1, yet to be reviewed GoldPlanar GL12, and flagship-class Audeze Euclid. The Euclid is far beyond the pricing of the 7Hz Timeless even with an ongoing Audeze B-stock holiday sale bringing it down to $649 as this is written. You get better technical performance from the Euclid for the increased cost, especially when it comes to the soundstage, which is remarkably good from a closed-back set of IEMs, but I dare say the 7Hz Timeless is tuned better. The other two are really not at all in the conversation, with the P.D.1 costing more despite worse tuning and poorer technicalities and the GL12 not even worth half its $199 asking price since it is a subpar attempt at an Audeze tuning and lackluster in execution in multiple ways. The 7Hz Timeless easily wins this round on merit alone before pricing even enters the picture.


Round two introduces the two new single DD hotties from DUNU and MOONDROP in a similar price range, both of which are tuned differently from the 7Hz Timeless, but present because I know people will be interested. The DUNU FALCON PRO is more a mid-bass monster, with stronger technical performance there, too. It loses out on the sub-bass magic the Timeless provides and is better-suited to different music genres, including pop music. The MOONDROP KATO is my personal favorite of the lot, but could admittedly do better with macrodynamics compared to the 7Hz Timeless that will be more appealing to the wider audience. I am also adding an under-recognized set here—the Ovidius RX-100 Qin Armour tuned similarly to the 7Hz Timeless while costing nearly the same too, and it will be more comfortable to wear as well. It's a tighter competition here than with the other two, and the 7Hz Timeless only pulls ahead by virtue of its strong points being further ahead of the Ovidius RX-100 relative to its deficits in the highs, while also looking cleaner in use.