Fit and Comfort

There are subtle fit differences between the different ear tips included with the FiiO x Crinacle FHE:Eclipse, at least for the same size. It's hard to see on the camera front-on, however. As such, I chose to show only one such size M ear tip (balanced) installed on the right IEM and 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, and I generally preferred the balanced ear tips here, which come pre-installed, effectively making these the default tips. You may want to consider using the foam tips for a better seal while potentially dampening the treble response, too. The size of these IEMs generally won't be an issue, but those with a smaller concha may struggle getting these fully in to make the most of the ergonomic shell design. The two vents also are not large enough to affect passive isolation, of which there is plenty here to avoid a seal issue if paired with the appropriate tips. The IEMs weigh ~7.2 g each, and the cable is slightly under 25 g in total. The angled adapter on the cable makes for a secure and comfortable fit hooking over the ears and on to the back, where you would ideally have it continue down the back to minimize microphonics. But I acknowledge that most will just have the cable draped down the front, so a combination of the cable cinch and clip will help.

Audio Performance

Audio Hardware

The FiiO FH3 is one of only a few IEMs with a name that reveals a lot about its workings, with the "F" for FiiO, "H" indicating the hybrid driver configuration, and "3" standing for the number of involved drivers. The FHE:Eclipse is a re-tuned take on the same, with the internals remaining the same. There is a beryllium-plated 10 mm diaphragm dynamic driver to handle the low frequencies, with the plating meant to make for a stiffer diaphragm, one that is more responsive to magnetic flux. The mids are catered to by a single Knowles ED-30262 balanced armature (BA) driver, with the Knowles RAD-33518 BA working on the high frequencies. The marketing talk on the FH3 product page is something else when it comes to superlatives, but I expect no less from any company aiming to sell a product in a competitive market.

The ED-30262 is placed in the nozzle, and thus closer to the ear to minimize treble reflections as per FiiO, which is part of the company's patented S.TURBO acoustic design with turbine-inspired sound tubes. The two vents are handy for preventing pressure build-up, as well as pressure relief for comfortable listening over longer periods of time. Driving the hardware isn't hard given the rated impedance of 21 Ω and slightly above average sensitivity of 111 dB/mW at 1 kHz. A standalone DAC/amp intended for high sensitivity earphones is not a bad idea thus, if only to run at lower volumes without clipping or a hiss, and going with one of the portable Bluetooth options we have covered before also makes this a wireless solution. The lack of a 3.5 mm audio jack for most phones these days is another reason to consider a DAC/amp that takes digital input and provides a 3.5 mm jack since you will otherwise have to use an adapter anyway, or even a dedicated DAP. If not on the go, space is less of an issue, but the relatively short cable 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 emphasizing a slightly elevated bass and smooth treble range with 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 and not 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 FHE:Eclipse, 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 identical in the lows and mids proper before the slightest of deviations begins and then gets worse with increasing frequency. Noting that measurements past the coupler resonance frequency of ~8 kHz are best taken with a grain of salt, there was still enough of a channel imbalance in this region to my ears that I spent an hour to make sure the measurements were fully reflective of my own experiences. Indeed, the biggest issue to me was the 4.5–6 kHz range even though the 8–11 kHz region measures more distinctly. This is still within tolerances and can be chalked up to unit variance, but remains a less than ideal scenario nonetheless. Measurements taken after 20 hours of testing, including with these playing a mix of various songs as well as white or pink noise and sine sweeps, showed no difference. There was no perceived burn-in effect thus, and none was measurable either. The response with the artificial pinna in place matches the ideal scenario in the coupler well enough, including with the typically seen resonance shift.


This is the average frequency response for both channels of the FHE:Eclipse plotted against my personal target taken from VSG.squig.link, which also gives you an idea of my personal preferences to better correlate any possible biases. The tuning of a set of headphones or earphones does not have to match my target as long as it is tuned with some direction, makes sense, and is executed well. After all, no one set will appeal to everyone, and having different options is what makes this hobby so interesting and hard to quantify. That being said, I do appreciate that Crinacle was upfront about who the Eclipse is and is not for, including by publishing the expected frequency response graph prior to the product going up for pre-order. Indeed, its unofficial tagline is "FU Bass," and you can fill in what FU stands for, albeit not in the sense that bass is being f'd; instead, the bass response is going to eff you up!

The FHE:Eclipse is not a balanced set of IEMs, so let me put that out there already. It's heavily bass emphasized such that I would not personally use it for my specific listening tastes. If you happen to listen to the music genres I do, you most likely will not enjoy the FHE:Eclipse either. But I get what Crinacle and FiiO were trying to do here and even admire it, which will get clearer in the comparison section below, although I will mention that I have not heard a single IEM tuned like this before. It may be my inexperience speaking, but a heavily bass-emphasized set with proper pinna gain and decent treble extension does seem like a unicorn, and that is the market the Eclipse targets.

Let's talk about the bass then, shall we? After all, this is what you should consider the FHE:Eclipse for. It has a whopping ~12 dB bass gain from the mids, enough to make ardent bassheads happy and potentially lower the volume too. The bass gain is well executed, and this is what makes the FHE:Eclipse more than just another set with a heavy V-shaped tuning. There's no mid-bass bloat, with the sub-bass equally respected to cater to EDM and house music in particular. 50 Hz onward is where rock music aficionados will find comfort, and whether you like it or not, bass guitar notes will leave several impressions in your head. This was my particular issue with the set, whereby I could not help but notice some music notes resonate far more than others.

Notice that the SPL gain starts at around 500 Hz going down, so the bass bleeding into the lower mids is going to be a love or hate affair. Knowing the FHE:Eclipse potentially matches the likes of heavy metal and rock, I decided to test for this by listening to Motörhead and Lemmy—rest in peace—growling into my ears, and the lower mids here suddenly convinced me there was no issue where I thought there clearly would be. His vocals worked very well, with the energy also provided to the drums and guitars there, and it ended up carrying over to other examples in the genres too. It is certainly genre-specific though, if not even song-specific, with other male vocal categories, such as country music and pop, not coming off as well in my opinion. What I don't believe is a love or hate affair is the technical performance, and the FHE:Eclipse is quite competent in that regard. It's hard for me to define contrast and slam separately from the tuning itself, but there's enough weight behind the notes for impact, and others I had listen to the FHE:Eclipse concurred. The FHE:Eclipse remains detailed enough to resolve between instrument classes; I would not call it very resolving either, which too is somewhat conflicted by the tuning, as seen below. I would have liked quicker decay between notes, with layers being what somewhat detracts from faster music genres. The soundstage and imaging are plenty enough within the market segment the FHE:Eclipse operates in, with a relatively compact soundstage that comes off more intimate than empty, and imaging is precise enough to pinpoint music sources within this imaginary field.

I have not heard the FiiO FH3 before, but independent reviews show that the tuning from 500 Hz onward is.. acquired, shall we say? A pinna gain split into various segments starts at 500 Hz, which some HRTF models will agree with, but the FHE:Eclipse is clearly not just a bass-boosted FH3 given the larger range in the mids and a much more properly defined in-ear resonance compensation peak where I expect it. I also see some signs of the crossover between the drivers, but this segment is essentially far more nuanced than bass-boosted sets would be to where female vocals come off sounding proper. Not forward or backward facing, just proper with a sense of neutrality. The treble response is non-fatiguing, but given my personal unit had the channels not exactly matching up, I find describing what you will exactly get difficult. It's certainly non-fatiguing, and there's decent treble extension, but various instrument class fundamentals and harmonics felt with other Eclipses may not match what you see above necessarily. Still, this is not a set I would recommend for classical music anyway, making this is a moot point.

Comparisons

I have had my fair share of bassy IEMs before, and the FHE:Eclipse somehow looks right in place with these next to it. It still has the most bass elevation of the lot, and these are just the tip of the iceberg of bass-boosted or heavily V-shaped IEMs. The FiiO FD3 is similar in tuning to the FHE:Eclipse, which is not a surprise in itself, although it still shows some signs of the pinna gain peaking in the wrong place, which the FH3 had to be rectified for here. There are a bunch of other IEMs I could show here, including some hybrids and single-DD sets, but I will again link to VSG.squig.link for you to play with and compare against other sets. Not having enough similarly priced sets also means it's not the easiest to do direct comparisons, and pretty much all the recently hyped releases (7Hz Timeless, MOONDROP KATO, etc.) are more balanced sets that are tuned very differently from the FHE:Eclipse, as well as more expensive to boot.


Remember when I said the FHE:Eclipse is clearly not wanting to be another balanced set and is instead its own thing? I thought it would be funny to compare it against the two bass-emphasized Campfire Audio entries I have reviewed to date, which are the Honeydew and Mammoth. Campfire Audio tends to make one-off tuned sets rather than iterative takes on a house curve, which is divisive to say the least, but makes for a product portfolio that will appeal to a few specific genres very well from time to time, and the FHE:Eclipse doing similar was hilarious enough to me to go ahead with the comparison given the entities involved don't get along well, either. Regardless, both the Honeydew and Mammoth are excellent examples of one-trick ponies with bloaty bass, which the Eclipse thankfully strays away from. The Mammoth does punch better and arguably is the more technical set, but needs EQ to really be in consideration, and this is before the $550 price point squashes this as a valid comparison altogether.