Fit and Comfort

Given the JD3 is a straight-insertion set of in-ear monitors, it would be a fair assumption that it will fit just about anyone. The smaller size and bullet-shaped shells directly enter the ear canal similar to what we saw with the TinHiFi T2 Evo, but taken a step further. The cable also coming straight down means you have more leeway in positioning the IEMs in the ears than with the more common approach of the cable going around the back of the ear and being a support point at the top. The JD3 is held in place just by the fit then, which makes a good seal all the more critical. These weigh a total of 19.3 g with the cable, and under 5 g each for the individual shells with drivers inside. As such, these are not physically fatiguing at all. I still recommend finding a cable clip to secure the cable to your shirt, if only to help with potential cable microphonics in use. The semi-open nature of these IEMs also means passive isolation isn't high, which does increase the comfort factor when using these for longer periods of time. I will also give a special shout out to the in-line controls and microphone, which are positioned very well. The microphone nicely picks up my voice for phone calls, and the in-line controls use highly tactile buttons for volume control, media playback, and answering incoming phone calls. The microphone works plenty fine for online calls, but will be bested for audio quality by the larger transducer fitted onto even gaming headsets that aren't known for their microphone quality much.

Audio Performance

Audio Hardware

As with just about anything under the FiiO label, the product page for the JD3 showcases the internals in good detail. Unsurprisingly, a single dynamic driver is used, and FiiO is using a 9.2 mm composite diaphragm driven back and forth by neodymium magnets. A copper-clad aluminium wire (CCAW) voice coil is implemented for its increased conductivity over most other budget options, and the acoustic chamber has a dual-cavity design that is marketed to produce faster bass transients. In the smaller inner cavity lies the driver itself, and near it is placed sound-absorbing foam to minimize the impact of standing waves and unwanted reflections for a more natural sound signature with increased resolution. The semi-open shells help in this regard, while also improving pressure balance throughout to minimize discomfort when listening.

All this comes together to make for a set of drivers of average rated impedance (16 Ω) and sensitivity (107 dB/mW), which makes the FiiO x JadeAudio JD3 no harder or easier to driver than the vast majority of other IEMs on the market—a standalone DAC/amp isn't really needed. That said, going with one of the portable Bluetooth options we have covered before also makes this a wireless solution, and the lack of a 3.5 mm audio jack for most phones these days is another reason to consider a DAC/amp for portable use. If not on the go, space is less of an issue, but the relatively short cable might still be a potential handicap if connecting to a PC as the audio source. I was able to get plenty of juice from my laptop's Realtek audio codec-powered 3.5 mm jack even with the volume in Windows set to 50%.

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 FiiO x JadeAudio JD3, or at least the audible part of it. 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 for all intents and purposes. Given reviewers such as myself get a randomly chosen single sample more often than not, the best way to test for driver reproduction and consistency is by comparing the two channels to each other, and even that small discrepancy at ~150 Hz is a measurement artifact! Measurements taken after 25 hours of testing, including with these playing a mix of various songs as well as white/pink noise and sine sweeps, showed no differences, either. There was no perceived burn-in effect thus, and none was measurable. The response with the artificial pinna in place matches the ideal scenario in the coupler very well but is affected by fit, so I did not bother to show it here.


This is the average frequency response for both channels of the FiiO x JadeAudio JD3 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, this set is tuned with a V-shaped signature in mind, and it's a gentle enough slope, also often described as a W-shaped tuning depending on where you stand.

FiiO's marketing department is working overtime attempting to make this budget-oriented set appeal to audiophiles, with plenty of hype thrown around. In general, FiiO states that "special care was taken to ensure that the highs and mids were transparent and suitably bright without sacrificing powerful and textured bass," accompanied on the product page by a factory frequency response curve, which I always like to see. It matches my own measurements well enough, although I have more of a roller coaster in the treble range. To be honest, I think the factory curve looks overly bright, and I am glad it's not as elevated in the highs here, which does throw a potential wrench in the cogwork I have been building up about channel matching and driver reproducibility. Regardless, I can only speak for my own experience.

Given the nature of these, I'll keep things simple here by telling you that the FiiO x JadeAudio JD3 does not punch above its weight by much. The primary thing is that the tuning is fairly decent to appeal to many different music genres, including with an elevated bass of ~10 dB in the sub-bass region, with decent extension in the lows for a sense of hard-hitting notes with the likes of EDM music, but without much power behind them. This is especially so when listening to rock music, where guitars and drums just don't have that kick associated with the music to make it fun to listen to. In fact, that's the issue—the technical performance of the drivers is barely present where it matters. I suspect the magnetic flux isn't as high as with more expensive sets, so the chosen magnets are a product of BOM costs and binning, if you will. I also do not know the actual composite diaphragm composition—it could play a role, too.

So treat this more as a gateway entry to audiophilia, with the warm lower mids potentially being the strongest point. There is minimal distortion and increased resolution for male vocals compared to the sub-bass region, which is found wanting, and the reproduction of recorded music in a studio comes off quite well. The mids otherwise start to suffer from poor imaging and soundstage, including where it's at a point hard to distinguish instruments properly. The pinna gain to the upper mids is typical FiiO as it is being compensated for earlier than most research would dictate, and I had the sense of slightly shouty female vocals coming with it. The treble region is otherwise decently balanced, but certainly not as natural in timbre as FiiO would like it. This might be the first time I've had a dynamic driver set come off metallic in this regard, but that's not as much an issue as the potential sibilance you may experience. On the plus side, it's not fatiguing to listen to. I still would not use the JD3 for music monitoring or even simply listening to classical/orchestral music. Pop/jazz/country music is where I can see the JD3 working out well enough, but even this is song-to-song dependent. Think Jimmy Hendrix more than Blackpink for a better idea.

Comparisons

In theory, I should have probably measured and included some of the KZ IEMs I have here. In practice, I don't know when I will get to them in the presence of what feels like a million different pending review items, so I did not want to hold off this review. Rest assured that I will talk more about the FiiO x JadeAudio JD3 in subsequent reviews of more budget-friendly IEMs too. As it stands, I have here two of the other relatively inexpensive IEMs reviewed to date, the Tripowin TC-01 and TinHiFi T2 Evo. These are both ~$50 sets that use a single dynamic driver, but all three are quite different from each other even tonally. The JD3 might be the most balanced of the three here, so the tuning is again a point in favor of the inexpensive FiiO offering. The TC-01 shows its technical prowess over the JD3 easily, with actual impact behind the bass boost and improved resolution and imaging even though it isn't a set of IEMs I'd recommend for that criteria. It's almost thrice the cost of the JD3, too, so keep that in mind since that's the difference between buying something on a whim as opposed to saving up for it. It also comes with a carry case and more accessories, as does the TinHiFi T2 Evo, but I'd certainly take the JD3 over the T2 Evo, which says more about how unappealing the T2 Evo is for most IEM users than anything else, though.