The TRUTHEAR x Crinacle ZERO RED are wired audiophile IEMs. They're an updated version of the TRUTHEAR x Crinacle ZERO, with the manufacturer claiming that these have undergone much more than a simple facelift. While they retain the same dual-driver design, changes in the voice coils and crossover circuits have resulted in a new tuning that strays from the original's mission to stay close to the 2019 IEM curve. This edition instead represents the kind of less bass-forward tuning that's preferred by Crinacle, one of the internet's most well-known IEM tuning experts. That said, for those that might miss the low-frequency oomph of the previous generation, they come with a handy 10ohm resistor that can boost the bass response.
The TRUTHEAR x Crinacle ZERO: RED are good for neutral sound. Their revamped tuning is less excited than the original and features a bass and mid-range response that's more closely aligned with our target curve. As a result, kicks and basslines sound present and loud without overpowering the detailed reproduction of vocals and lead instruments. There's even a 10ohm resistor supplied, which will alter the sound profile to provide more bass. The treble range is a little veiled, so sibilants, like cymbals, lack some presence and sizzle. But a couple of small peaks in the otherwise controlled treble region mean sibilants of specific pitches can sound a touch harsh. Otherwise, they deliver audio very consistently. Like most in-ears, their passive soundstage isn't very immersive and lacks width and openness.
The TRUTHEAR Crinacle ZERO: RED are disappointing for commute and travel use. While they're comfortable, portable, and well-built, they struggle to isolate you against a lot of background noise, especially lower-frequency sounds, like the rumble of bus engines. They're a little better at blocking out the mid-range sounds of a busy street, but the passive isolation provided by their in-ear fit still falls flat when compared to ANC-equipped alternatives.
The TRUTHEAR x Crinacle ZERO: RED are okay for sports and fitness use. They're lightweight, comfortable, and have a stable fit. They're also well-built, though they lack a certification against water or dust damage. They're primarily hampered for this use by their wired design. Although the cable is detachable, it can easily be yanked while in motion, which can result in damage to the connectors. They also don't have an dedicated physical controls for inputting commands while you're mid-jog.
The TRUTHEAR x Crinacle ZERO: RED are disappointing for office use. Despite their comfortable, stable fit and solid build quality, they struggle to block out common office sounds, like background chit-chat and the scraping of chairs. They also don't have a mic, so you'll have to switch to a headset or use a standalone mic to take calls. That said, they barely leak any audio, so you won't have to worry about disturbing your colleagues even if you blast your music.
The TRUTHEAR ZERO: RED are wired-only headphones; you can't use them wirelessly.
The TRUTHEAR ZERO: RED are passable for wired gaming. Thanks to their wired design, they have a latency-free performance. They also feature a comfortable in-ear fit suited to long gaming sessions. Their generally balanced sound profile is great for rendering bass frequency sounds, like explosions, with plenty of substance without overshadowing the detailed mid-range. On the other hand, their slightly veiled treble response will result in sibilants, like S and T sounds in dialogue, sounding a little lispy. They also have a poor soundstage performance, making it harder to locate in-game audio cues within the stereo field, especially compared to using an open-back pair of headphones.
The TRUTHEAR ZERO: RED don't have a mic; you can't use them for phone calls without a standalone microphone.
The TRUTHEAR x Crinacle ZERO RED are wired IEMs designed to deliver audiophile-quality sound. Not to be confused with the original TRUTHEAR x Crinacle ZERO, these buds come in one color variant: 'Red.' The two variants boast an almost identical feature set, with the main point of differentiation being the tuning. You can read more about this in the Sound Profile of the review. If you encounter another variant of these headphones, please let us know in the forums and we'll update our review.
The TRUTHEAR ZERO: RED are wired IEMs. They're a re-tuned version of the TRUTHEAR x Crinacle ZERO, so comparing them to the original version is natural. The 'RED' features a tuning that's less focused on following the Harman 2019 IEM target curve and developed instead with Crinacle's own listening preferences in mind. As a result, the new version reins in the original's buoyant, in-your-face bass response and replaces it with something more balanced. The treble range is also more veiled. Besides a change in the color and design of the decorative panel and the inclusion of the 10ohm resistor, there are no other differences in features. Those with a bigger budget who desire a more prominent treble response might also want to consider the MOONDROP Blessing 3, although they're considerably more expensive.
If you're looking for more headphones, check out our recommendations for the best audiophile headphones, the best headphones for music, and the best wired headphones.
The TRUTHEAR x Crinacle ZERO: RED are a better choice for fans of bass-heavy genres than the TRUTHEAR HEXA, which lacks a little thump in the low end. On the other hand, Jazz fans may appreciate the more detailed treble of the HEXA. The RED are a bit cheaper than the HEXA, but the HEXA are slightly better at blocking out noise, though neither pair have ANC.
The TRUTHEAR x Crinacle ZERO: RED and the TRUTHEAR x Crinacle ZERO are, by and large, the same pair of IEMs, albeit with different tunings and a slight difference in noise isolation performance. They're both comfortable, well-built, and stable-fitting, but the RED variant aligns more closely with our target curve, with a more controlled bass in particular. They're also better at isolating mid-range frequencies, like the chatter of your colleagues in an office setting. On the other hand, the RED have a recessed treble that will be less appealing to people who like a more excited sound with a bit more sizzle. It's worth noting that the RED variant comes with a 10-ohm impedance adjustor, so you can always purchase this variant and use the adjustor if you prefer a more bass-heavy sound.
The MOONDROP Blessing 3 are better in-ears for neutral sound than the TRUTHEAR x Crinacle ZERO: RED, which is unsurprising given their higher retail price. These premium IEMs feature a hybrid driver design with two 10mm dynamic and four balanced armature drivers. As a result, they have an extremely balanced sound across the board. They also have a sturdier build quality and come with a more secure case for storing them when they're not in use. That said, the TRUTHEAR offer a very good price-to-performance ratio, given they're a fraction of the price of the MOONDROP but feature a comparably balanced sound. They also have a slightly punchier bass, which EDM fans might appreciate.
The MOONDROP Aria and the TRUTHEAR x Crinacle ZERO: RED are similarly priced wired audiophile IEMs. While the MOONDROP are more comfortable and deliver audio more consistently, the TRUTHEAR deliver a more balanced sound across the entire frequency range. They also do a better job of blocking out external sound across the entire frequency range.
The TRUTHEAR x Crinacle ZERO: RED are better overall in-ears than the KZ ZS10. The TRUTHEAR have a more balanced sound across the entire range and are more comfortable to wear for extended listening sessions. They also feature a 10ohm adaptor for additional tuning, in case you prefer a more bass-heavy sound. The KZ are slightly better built and have a very durable plastic casing.
If you prefer a sound closer to our Harman-based target, you'll want to check out the TRUTHEAR x Crinacle ZERO: RED over the Sennheiser IE 200. While both buds are similarly comfortable and well-built, the TRUTHEAR x Crinacle has a punchier bass and a bit more detail in the treble range. However, you may still prefer the Sennheiser's sound if you're looking for a bit less bass than our target and a more recessed treble to help keep ear fatigue at bay if you're monitoring a show.
The TRUTHEAR x Crinacle ZERO: RED and the THIEAUDIO Monarch MKIII have similar sound profiles but very different prices. If you like a warmer, smoother sound, either of these pairs will suit you well. That said, the THIEAUDIO leak less audio and do a better job blocking out external noise, but they are significantly more expensive. Whether the improvements are worth the cost is up to you.
The TRUTHEAR ZERO: RED have a very similar teardrop-shaped design to the original TRUTHEAR x Crinacle ZERO. They feature the same braided, detachable cable as their sibling, but their 3D-printed resin cavity is covered in a decorative panel that's finished in a strikingly figured crimson red. Internally, there's a similar configuration of drivers with a 10mm dynamic driver handling bass frequencies and a 7.8mm driver responsible for the mids and treble.
The TRUTHEAR ZERO: RED have a comfortable in-ear fit. You can choose from the six sets of silicone ear tips and one set of foam tips to ensure a great fit, but we found the foam pair provided the best seal. Their shape is well-suited for most ears, but the wire connector would sometimes slip off the bud itself when the fit was adjusted, especially in a twisting motion.
These in-ears are exceptionally portable. They're extremely lightweight and take up minimal space in a bag or pocket. You can also detach their cable for separate storage, and they even come with a carrying pouch.
The included carry case is identical to the one provided with the TRUTHEAR x Crinacle: ZERO. It's made of a supple faux leather material with a soft velvet interior. It's designed more for storage than protection, and there's nothing in the way of extra storage compartments.
These buds have a good build quality. The enclosure is made of a sturdy 3D-printed resin with a glossy plastic exterior. You get sets of foam and silicone tips, and both materials feel reliable, although the foam tips are prone to becoming somewhat dislodged. The nozzle that they're attached to is on the longer side, too, so it might take some trial and error if you plan on using a non-stock pair of ear tips. The cable is braided and double-sided, but its construction is a little flimsy and prone to wear and tear. The connectors used to attach the cable ends to their respective earbuds also need to be handled with care. When connected, they don't form the tightest fit either and tend to slip out of place when handled. There's a similar lack of friction with the 10-ohm adaptor, which can feel wobbly when plugged in due to its length.
Once you find the right pair of ear tips, these buds have a stable fit. We tested them using the foam tips and found that they can stay in place during moderate to intense exercise. They'll stay in your ear during a light jog, for example, but you run the risk of snagging the cable on something, which will dislodge them from your ear.
While the original TRUTHEAR x Crinacle ZERO were designed to closely follow the Harman 2019 IEM target curve, this new edition is a deliberate and intentional deviation from this tuning. This new tuning is described as 'more palatable' by Crinacle in a video showcasing the ZERO: RED, which in this case translates to a similar sound profile that's more reined in. The low end is less exaggerated, and the treble range is more subdued. As a result, kicks feel tighter, with more controlled punch and thump. Basslines are still present but dominate the mix less than they did with the original ZERO. The mid-range generally follows our target curve well, with a slight boost in the high-mids that keeps vocals at the front of busy pop mixes. The treble range is slightly more inconsistent, though, as a balanced low-treble response is juxtaposed against a recessed mid-treble that somewhat dulls sibilants. If you're a fan of vintage-sounding music, you might appreciate this smooth top end.
There have been accommodations made for those who prefer a more bass-heavy sound profile, too, as these buds come with a 10-ohm adaptor that alters the impedance slightly to add more low-end thump to the sound profile. It's more of a subtle boost than a drastic change in sound, but it'll also lower your output level slightly, which you'll need to adjust for. You can see how this alters the sound profile here.
It's worth noting that we had some trouble getting a solid fit on our testing head with the right earbud, and as a result, our measurements for the right driver are slightly skewed. We don't expect this to be an issue that would affect you during everyday use, though.
These in-ears have excellent frequency response consistency. Once you achieve a solid fit with the right pair of ear tips, you'll be treated to consistent audio delivery every time you use them.
The bass-range target compliance is exceptional. This new tuning is much more closely aligned with our target curve than the TRUTHEAR x Crinacle ZERO. The low- and mid-bass is slightly overemphasized, giving kick drums a little extra thump and punch. A small dip in the high bass keeps basslines from sounding boomy. In songs like Justice and Tame Impala's Neverender, both the kicks and the bassline sound present and powerful but never overpower the rest of the mix.
The mid-range target compliance is excellent. The low-mids are ever so slightly recessed, which helps prevent dense mixes from becoming cluttered. The mid-mids follow our target almost perfectly, so vocals are present without sounding boxy. Finally, the high-mids are slightly boosted, which ensures instruments sound clear, if a touch harsh. On tracks like Alesis by Mk.gee, the vocals sound distinct and clearly differentiated from other mid-range instruments like snares and synthesizers.
These IEMS do a great job following our target curve. The lower part of this range closely follows our target, meaning instruments sound detailed but not harsh. On the other hand, the mid-treble is a bit recessed. Some users may like this, as it lends these IEMS a slightly warm sound and reigns in sibilance, but it can also make vocals and cymbals sound dull. If that smoother sound appeals to you, you might also want to consider the THIEAUDIO Monarch MKIII.
The TRUTHEAR ZERO: RED have very good peaks and dips performance, meaning they follow their own sound profile well. A small dip in the high bass is likely where the drivers cross over, but it doesn't affect the sound much. At the other end of the spectrum, a small peak in the low treble and a bigger peak in the mid-treble mean sibilants can sound a bit harsh, depending on their pitch.
The imaging performance is exceptional. Our unit's L/R drivers are very well-matched regarding phase, amplitude, and frequency. Group delay also falls below audible levels across the entire range, resulting in tight bass and transparent highs. Great imaging is usually indicative of solid quality control and ergonomics, and given the original ZERO also scored well in this regard, this is demonstrative of a fruitful collaboration between TRUTHEAR and Crinacle.
As with other in-ear monitors, the TRUTHEAR ZERO: RED have a very bad passive soundstage performance. By design, they bypass your outer ear, meaning there's no interaction between sound waves and your pinna. The resulting soundstage is small, closed-off, and unnatural-sounding.
The weighted harmonic distortion performance is great, and audio is clean and pure-sounding even at higher listening volumes. Crinacle advertises that you can push these IEMs to 115dB without noticeable distortion, but we don't recommend exposing your ears to these kinds of volume levels.
These are the settings used to test the TRUTHEAR ZERO: RED. Our results are only valid when used in this configuration.
The TRUTHEAR ZERO: RED have a decent noise isolation performance, surpassing their predecessor's, but falling short of the TRUTHEAR HEXA's. While they don't have an ANC feature, their in-ear fit means these buds provide some passive isolation against ambient sound. As a result, they block minimal amounts of bass-range noise but do a better job of isolating against mid-range sounds. They're great at blocking out treble-range sounds, like fridge hum. Their improved noise isolation performance compared to their predecessor is likely due to a change in the makeup of the foam tips. While they look identical to those that came with the previous generation, these new tips have a little less spring to them. You can see a graph of our results comparing the performance of the foam tips and silicone tips here. While they block out a similar degree of noise in the bass and mid-ranges, the foam tips provide more isolation against treble range sounds, especially if they're loud.
The TRUTHEAR ZERO: RED struggle to block out everyday sounds. They struggle to block out the roar of airplane engines and office sounds, like chatty coworkers and chairs scraping. That said, they're better at blocking out street noise sounds, like blaring car horns and traffic.
The leakage performance is excellent. The leakage is concentrated in the high-mid range, so escaping audio sounds thin and lacking in body. However, the overall volume is so low that others around you won't be disturbed by your audio, even if you're in a quiet environment and cranking your tunes.
The TRUTHEAR ZERO: RED come with a detachable braided audio cable. It's a 1/8" TRS connector, so you'll need a separate mic to input audio. They also come with a wired 10-ohm resistor that you can use to increase the bass, which lowers the output somewhat. The resistor uses the same 1/8" TRS connection and can be plugged directly into the cable.
These in-ears are compatible with PCs via a 3.5mm jack. However, you'll need to purchase a separate mic to input audio.
These headphones only support audio when connecting their 1/8" TRS cable to your PlayStation controller. If you want to send audio in addition to receiving it, you'll have to use an external microphone.
These buds only support audio when plugged into your Xbox controller's AUX port via the included audio cable.