Below is my review of the Tanchjim Oxygen. You can also read it on my blog.
The Tanchjim Oxygen is an in-ear monitor with a single 10mm diamond-like carbon diaphragm dynamic driver per side. This review is based upon a retail unit purchased by me at list price for personal use from Linsoul Audio.
SOURCES
I have used the Tanchjim Oxygen with the following sources:
Windows 10 PC > JDS Labs The Element > Tanchjim Oxygen
Pixel 3 > Fiio BTR1K (Bluetooth Apt-X) > Tanchjim Oxygen
Windows 10 PC > Fiio BTR1K (USB-DAC) > Tanchjim Oxygen
Pixel 3 > Apple USB-C to 3.5mm dongle > Tanchjim Oxygen
I have tested these headphones with local FLAC and Spotify Premium.
PACKAGING AND ACCESSORIES
The Tanchjim Oxygen comes in a mid-sized grey cube-shaped package. The front panel of the slipcover bears a rendering of the IEM, as well as the model name, the Tanchjim logo, and manufacturer tagline “Feel more, Hear more.” The left- and right-side panels bear the Tanchjim logo and the model name, respectively. The back panel of the slipcover shows an exploded diagram of the IEMs, along with specifications and manufacturer contact information. This information is presented mostly in Chinese.
Underneath the slipcover and a top lid removing the slipcover reveals a series of smaller overlapping boxes, the topmost containing the eartip selection, a warranty card, a card indicating how to attach the cable, a QC pass chit, an owner’s manual, and a set of 20 spare nozzle filters. There are two sets of dark grey silicone eartips, one set of short, wide bore tips (S, M, L) and one set of more typical eartips (S, 2xM, L).
Underneath this top box is a mounting foam sheet holding the IEMs faceplate-up, and a box containing the zippered carry case. The carry case is on the small side, made of dark grey leather embossed with the Tanchjim logo in black. The carry case will fit the IEMs with either of the included cables, but if you use a bulkier braided aftermarket cable with the Oxygens you will likely need a larger carry case. The two included cables are stored underneath the foam mounting sheet.
BUILD QUALITY / DESIGN
The Tanchjim Oxygen’s housings are polished dark grey stainless-steel slabs in the shape of a heavily rounded right triangle. The machining and polish are impeccable. The left and right faceplates bear the model name and manufacturer’s logo in black. The standard .78mm 2-pin cable connections are flush with the housing on the forward-facing side of the IEM. “Tanchjim Oxygen” and “L/R” is written on the inner surface of the housing in silver. The forward-swept short nozzles protrude from the bottom corner of the housing. The serial number is written in silver around the nozzle of the right earpiece.
Each earpiece has two circular vents, one above the nozzle on the inner side of the housing, and one on the rear-facing side. There is no driver flex, but I did experience diaphragm popping upon first insert in the first day of using the Oxygens. This only occurred while using dual-flange eartips. The nozzles have substantial lips, which facilitated use with a wide variety of eartips.
The 2-pin connections are snug and secure, but are slightly recessed, limiting alternative cable options. The mic’d cable is encased in a black rubbery sheath, while the OFC silver plated cable is enclosed within a clear plastic sheath. Both cables have straight 3.5mm terminations, use pre-formed plastic ear-guides, and have blue or red dots on the 2-pin housings to indicate left or right. The silver cable has a choker, but the mic’d cable does not. The silver-plated cable is flexible but does have minor microphonics. The mic’d cable is more microphonic than the silver-plated cable. Neither cable is prone to tangling. The pause control on the mic’d cable works as intended, but the +/- volume controls trigger an increase or decrease to maximum or minimum volume rather than a single volume step change. I did not have the opportunity to test mic call quality before writing this review.
COMFORT / FIT / ISOLATION
The Tanchjim Oxygen is intended to be worn cable-up only. The Oxygen has a shallow insertion depth and the housings are on the small side, but because the cross-section of the Oxygen is more aesthetic-focused than ergonomic I did experience some discomfort after prolonged wear over the course of several weeks.
Extensive tip rolling is essential. For me, getting a secure fit and a good seal was troublesome with any but the largest conventional silicone eartips. I settled on using Sony Hybrid type tips, which are made of a grippier material than most eartips. Double or triple flange eartips will also work. Noise isolation is average for a single dynamic driver design.
SOUND
The Tanchjim Oxygen has a cool, neutral-ish tuning with an emphasis on presence, detail, and clarity.
The Oxygen has accurate, insistent bass. The well-extended sub-bass is slightly elevated compared to the mid-bass. The mid-bass is impactful yet precise and does not bleed into the lower mids at all. Bass comes across as textured despite the restrained presentation. There is some rumble but little slam. Bass articulation is lightning-quick.
The midrange tonality is dead neutral, and listeners coming from IEMs with a warmer tonality will likely find it cool. The lower mids are recessed compared to the upper mids, but male vocals are crystal clear. Both male and female vocals can overshadow instruments in the lower midrange. Female vocals are vibrant without being sibilant. There is enough presence to render detail and grit convincingly, but not so much that the IEMs are inherently harsh.
The treble is crisp and energetic with ample air and sparkle. Transients are very natural sounding. Resolution is outstanding but unforgiving to poorly recorded sources. Instrument separation is superb. Soundstage is small compared to hybrid or multi-BA designs but compares well to other single dynamic designs. The Oxygen is the first IEM I have heard that has “holographic” imaging.
MEASUREMENTS
My measurements were conducted with a Dayton iMM-6 microphone using a vinyl tubing coupler and a calibrated USB sound interface. The measurements use a compensation file derived from comparing my raw measurements with Crinacle’s published measurements. The measurements are presented with 1/24th smoothing. There is a resonant peak at 8k. Measurements above 10k are not reliable.
AMPLIFICATION REQUIREMENTS AND SOURCE PAIRING
With a sensitivity of 110dB and an impedance of 32ohms, the Tanchjim Oxygen can be driven to comfortable listening volumes with a smartphone or dongle but will benefit from the additional headroom provided by a dedicated source if one wants to listen at high volumes. I did not notice hiss with any of my sources.
COMPARISONS
Tanchjim Oxygen [$270] vs Nicehck M6 (brass filter) [$94]
The Oxygen has much more extended sub-bass. The Oxygen’s bass is faster, better articulated and is much less boomy. The M6 has more textured bass. The M6 has more slam than the Oxygen. Even with the brass filter, the M6 has more midbass bleed than the Oxygen.
The M6 has a warmer, less recessed lower midrange, and a more aggressive upper midrange. The M6 has more intimate midrange, while the Oxygen creates more space between the listener and vocals. The M6 is more prone to harshness and sibilance.
The M6’s lower treble is elevated compared to the Oxygen. The M6 has more sparkle but less air. The Oxygen has more realistic transients. The M6’s treble is splashy in comparison.
The Oxygen is more detailed and resolving. The M6 has a much larger soundstage. The Oxygen has better instrument separation and more precise imaging. The M6 is slightly easier to drive.
The Oxygen has a more premium unboxing experience and a greater variety of eartips. The Oxygen includes two cable variants and a higher quality case, but the case included with the M6 is larger. The M6 is tunable via swappable filters.
Tanchjim Oxygen [$270] vs Simgot EM1 [$60]
Despite the price difference between the two, the Oxygen and the EM1 have similar frequency responses. The Simgot EM1 has slightly better sub-bass extension. The Oxygen’s bass is faster and better articulated.
The two IEMs are nearly identical in frequency response between 40hz and 4000hz, where after the EM1 exhibits a pronounced 5k peak. With that said, the EM1 has a warmer midrange tonality and a slightly brittle timbre compared to the Oxygen.
The Oxygen has more air than the EM1. The Oxygen is significantly more detailed and resolving.
The EM1 has a slightly wider soundstage, but the Oxygen has better imaging and much better instrument separation. The EM1 is easier to drive.
The Oxygen is more comfortable but the EM1 sits more securely in the ear. The EM1 has a venting issue that the Oxygen does not have. The EM1 has a more premium unboxing experience and a similar variety of included eartips but does not include a real zippered carry case. I prefer the braided cable that comes with the EM1 to either of the cables included with the Oxygen.
CLOSING WORDS
The Tanchjim Oxygen is a lightning-quick, highly resolving IEM with outstanding instrument separation and imaging. However, the unboxing experience is underwhelming given the more premium packaging of IEMs which cost less than 1/3rd of the price of the Oxygen, and while the design and finish of the IEMs themselves are astonishing, the cables are disappointing at this price point. Commendable from a performance standpoint but not the best value in IEMs.