Introduction

TangZu Audio was previously known as T-Force until a trademark dispute forced the audio brand to go through a literal rebranding exercise. It decided to make the best of this scenario by adopting a theme based on China's Tang Dynasty—hence the name. Newer products also followed names of important people from said dynasty, including the Yuan Li and Shimin Li in-ear monitors. I have the Shimin Li here which is a ~$30 set using single dynamic drivers while looking like it could certainly cost much more. The build quality was also far exceeding the cost although the actual audio experience left me wanting to where I didn't even bother covering it. Then came news of a new planar magnetic set using the same 14.x mm full-range driver we've seen in the likes of the 7Hz Timeless, LETSHUOER S12, and the MUSE HiFi Power. Could this be TangZu Audio's savior?


The subject of today's article is the TangZu Audio Zetian Wu, named after the first empress consort of the Tang Dynasty who eventually usurped the crown—think strong female figure and you get the point. TangZu Audio wishes to evoke a similar result by having its take on the planar magnetic IEMs usurp the previous contenders when it comes to outright performance as well as value for money. Thanks to HiFiGo for providing a review sample to TechPowerUp as we put the Zetian Wu to the test today beginning with a look at the product specifications in the table below.

Packaging and Accessories

I suppose if there ever had to be artwork on an audio product depicting a person then TangZu Audio does have a reasonable claim to using artistic depictions of the person that the product is named after. The Zetian Wu accordingly features the empress on the front to go with the company logo and product name. The theme carries around the entirety of this external sleeve too. On the back are product specifications to go with contact information for the company, along with confirmation on which cable connector you went with. The inner box is plain thick cardboard in black color and has the TangZu Audio logo on it. It is clasped shut from the side via two magnets and opening the box reveals a thank you note followed by a compartmentalized sorting of the contents, including the IEMs placed inside a thick foam sheet for added protection.


The carry case is certainly a strong color and larger than usual for in-ear monitors. It has the company logo on the front and uses faux leather dyed burgundy to come off fairly convincing to the eyes and when handled too. The oversized zipper helps exude a sense of good build quality via placebo and then you open the case to a soft velour lining and compartments to easily hold the IEMs and cable. Speaking of which, the cable itself is found in a plastic zip-lock bag in the mesh compartment to the top that provides enough room to store spare ear tips as well as a portable DAC/amp too.


The IEMs come with a set of silicone ear tips pre-installed and there are plenty of others found in a separate accessory tray. These come marked for what they are supposed to do although TangZu Audio perhaps should have double checked the text here given the "foam" tips are another set of silicone tips in size M. As such, you get four types of silicone ear tips with the Zetian Wu of which two sets only come in size M and the other two come in sizes S/M/L. I've seen some of these ear tips used by others, including 7Hz, to good effect.

Closer Look

The cable that ships with the TangZu Audio Zetian Wu is plenty decent but won't win any awards by itself. There are two connector plug options on the source side in the form of the 3.5 mm single-ended TRS plug I have here or a 4.4 mm balanced plug that will increase the cost of the IEMs by $5-10 depending on the vendor. These are paired with metal housings which in turn lead to an all copper cable that makes of 4-strands, 224 wires of high purity oxygen-free copper conductor braided relatively tightly. This makes for a cable that isn't the most kink-proof but also one that likes to hold its shape and necessitates roadie wrapping owing to the lower pliability on offer. It's not microphonic at least, so functionally I have few issues. The splitter and the housing on the other end use a similar bare metal finish and the cable cinch could be tighter in holding the two channel cables in place. Furthermore, there is a highly curved set of pre-formed ear hooks which then lead to two 0.78 mm 2-pin connectors that have L/R markings on the housings for channel identification. The metal plugs are gold-plated for oxidation resistance and note the circular housing used for the flush 2-pin connectors here as opposed to the usual rectangular design.


The Zetian Wu employs a mix of DLP 3D printing (digital light processing, resin printing) for the resin shells themselves which get an opaque black finish. The shells are smooth to the touch and help keep the IEMs on the lighter side of average. These are capped by a CNC-machined aluminium face plate that is anodized to come off violet/purple depending on the incident angle to signify the royalty this set is named after. The design you see on the face plates are meant to be "auspicious clouds" although I personally am happy to see a new color scheme used on IEMs that doesn't go the gaudy route either. There are multiple vents on the sides and a flush-mounted 2-pin cable housing that should work well with the cable as seen above. The pre-installed ear tips are fairly generic but do the job well enough. Removing them exposes the stubby nozzle that measures in at 6.5 mm at the end so those with smaller ear canals might struggle. The nozzle also requires a deep fit for a good seal here to further compound this issue. There are notches on the nozzle to help keep the ear tips in place once installed as well as a fine mesh filter on the end to prevent contaminants from entering the acoustic chamber.


Here is a look at two other size M silicone ear tips installed on the right shell of the Zetian Wu. They differ in bore diameter and length generally, but do try them all out and see what works best for you. Note that you may also end up having different sizes for the two ears depending on the size of your ear canals, given these biological features won't necessarily be the same for everyone. Installing the cable is simple enough with the pre-molded ear hooks that go over the ears and L/R indicators helping identify what goes where. Push the 0.78 mm 2-pin plugs into the IEM connectors as seen above, and friction will do the rest in keeping them in place.

Fit and Audio Performance

Seen above is the right side of the TangZu Audio Zetian Wu installed in an anthropomorphic pinna that does well in showing my own experience with these. I have average-sized ears, and found the size M pre-installed silicone tips as well as the "balanced" silicone tips to work best. The shells are larger than average here although the ergonomic shape does help, to where I did not have any comfort issues myself. Those with smaller ear conchas and/or ear canals might struggle, however. The Zetian Wu is still going to hang out of the ear to an extent either way so the added support from the cable will be handy should the pre-molded ear hooks fit you well. In my case I had to take out a hairdryer to re-mold them for reasons evident from the image above. Note that you will have to push these slightly more into the ear canal owing to the stubby, thick nozzle and that provides for a satisfying level of passive isolation with a good seal all around. The shells weigh ~4.2 g each so there isn't any physical fatigue to be had.

The Zetian Wu uses the same 14.x mm planar magnetic drivers that have been used to varying degrees of success in the past, and note that this is different from the one used in the 7Hz Salnotes Dioko and DUNU TALOS, as well as the third variant of such drivers that is currently exclusively seen in the MOONDROP STELLARIS. There's not really much more to say here which has not already been discussed in the equivalent section of this review, so let me instead mention that the Zetian Wu is easy enough to drive off even a decent dongle, let alone a more capable portable DAC/amp. It has a rated impedance of 16 Ω and sensitivity of 100 dB which I would presume is 100 dB/mW based on my experience—when will companies understand the importance of proper units? I paired it with the Qudelix-5K and Questyle M15 for most of my listening experience.


Testing was done similar to all other IEMs, such as the recently reviewed FiiO FH7S. Seen above is the measured frequency response for both channels of the TangZu Audio Zetian Wu, which can be inspected further here if interested. Channel balance is very good on this sample and I'll also re-affirm there was no burn-in effect felt or measured here. The overall tonality of the Zetian Wu could be classified as U-shaped owing to that tuck in the mids, although really it comes off more neutral with bass-boost to my ears. Boosted indeed the bass is with nearly 12 dB SPL hike from the low point at 600 Hz and seemingly just increasing further courtesy that bass extension all the way down to 20 Hz and below. If you were ever wondering what planar bass sounds like then this is a textbook example of it with speedy notes that provides good appreciation of both leading and trailing ends of tones. I wouldn't say the Zetian Wu is the most dynamic set I've heard but it's still very good bass quality on top of that quantity to help with kick drums and bass guitars alike.

Vocals can be hit or miss depending on the fit achieved here since you do need to get the nozzle in deep to have forward-facing and engaging male vocals in my experience. Instruments are generally the star here with excellent separation, although you will experience a more metallic timbre here—especially if you are used to dynamic drivers. Female vocals sounded great to my ears courtesy the ear gain being accounted for well while not having a lot of upper mids/lower treble presence either to make it fatiguing. This also lends favorably to second-order harmonics for a lot of instruments that don't clash with fundamental tones in the treble. It can be found slightly wanting with complex orchestral pieces but the Zetian Wu works nicely for classical and jazz music as a whole. Do be aware that the air in the upper treble might be a touch hot for some!