The TFZ S2 Pro is an in-ear monitor with a single 11.4mm graphene-diaphragm per side. The S2 Pro retails for about $46 on
HiFiGo at the time of this review. The S2 Pro was provided to me by
HiFiGo in exchange for a fair and objective review.
HiFiGo has provided the following coupon code for $5 off the S2 Pro: TFZS2PRO
This review can also be viewed on my blog:
TFZ S2 Pro Review
SOURCES:
I have used the TFZ S2 Pro with the following sources:
Windows 10 PC > JDS Labs The Element > TFZ S2 Pro
Pixel 3 > Fiio BTR1K (Bluetooth Apt-X) > TFZ S2 Pro
Windows 10 PC > Fiio BTR1K (USB-DAC) > TFZ S2 Pro
Pixel 3 > Apple USB-C to 3.5mm dongle TFZ S2 Pro
I have tested these headphones with local FLAC, Spotify Premium, and Amazon Music HD. Visit my
last.fm page to get an idea of what I listen to.
PACKAGING AND ACCESSORIES:
The TFZ S2 Pro comes in a long rectangular white box with a clear plastic front panel, which displays the S2 Pro earpieces in a plastic tray. It appears to be the same packaging the Blon BL-03 comes in. TFZ’s contact information is listed on the back in Chinese and English. A sticker on the back indicates the selected color option. The S2 Pro comes with a detachable .78mm 2-pin cable, three pairs of short, wide-bore silicone eartips (S, M, L), four pairs of conventional grey silicone eartips (S, 2xM, L), and a TFZ-branded PVC carry bag.
BUILD QUALITY / DESIGN:
The S2 Pro has a two-part, plastic housing with a teardrop-shaped cross-section. The longest edge of the triangle faces forward. There are no sharp edges anywhere on the housing. The nozzle is swept forward from the bottom corner. There is one mesh-covered circular vent on the bottom corner of the outer faceplate, and one circular vent on the inner face of the housing. The nozzles have a small lip for securing eartips. The S2 Pro has severe driver flex.
The S2 Pro comes with a silver plated copper cable with a straight 3.5mm jack. The cable is enclosed in a synthetic fiber sheath. The 2-pin connector housings are angled and the pins are recessed. The cable is moderately microphonic. The 2-pin connectors have raised markings to indicate left and right. The cable has pre-formed ear-guides without memory wire. The TFZ logo is printed on the Y-split. There is no chin-adjustment choker. The cable is not tangle-prone. There is strain-relief above the 3.5mm jack but none at the Y-split.
COMFORT / FIT / ISOLATION:
The TFZ S2 Pro is intended to be worn cable-up only. The TFZ has a moderate insertion depth and I was able to get a good seal using the stock eartips. The earpieces do migrate out of the ears over time, but more slowly than the CCA-C10. I found the S2 Pro comfortable to wear for long periods. Isolation is above average, and I have not received any complaints about sound leakage.
SOUND:
The TFZ S2 Pro has a V-shaped tuning.
The S2 Pro does not have a mid-bass hump, instead emphasizing sub-bass over mid-bass. Sub-bass extension is respectable but not best-in-class. The bass region as a whole is elevated above the lower midrange. There is a good amount of rumble and but slam is less present. The bass has good speed and articulation. The bass is textured but can be boomy.
The lower midrange is quite recessed compared to the mid-bass. Male vocals retain passable intelligibility but are a little dry. Female vocals are further forward than male vocals. The overall midrange tonality is a bit thin-sounding. The overall timbre is passably realistic. There is a lot of presence and some sibilance.
The lower treble is elevated and a little harsh. The upper treble is noticeably rolled off. Transients are a little hazy. There is a not a lot of sparkle or air. Overall resolution and detail retrieval are unexceptional. Soundstage is above average in size for a budget single dynamic driver, while imaging and instrument separation are average.
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 relating my raw measurements with Crinacle’s published measurements. The measurements are presented with 1/24th smoothing. The magnitude of the valley around 7k is a coupler artifact. There is a resonant peak around 8k. Measurements above 10k are not reliable.
AMPLIFICATION REQUIREMENTS AND SOURCE PAIRING:
The TFZ S2 Pro can be driven to comfortable listening volumes with a smartphone or dongle. I did not notice any hiss.
COMPARISONS:
TFZ S2 Pro vs Blon BL-03
The Blon BL-03 uses a single carbon nanotube dynamic driver. It has a more neutral sound signature, with a more restrained bass presentation and a less forward upper midrange and treble response. I did not experience any sibilance or harshness with the BL-03 in comparison to the elevated upper midrange and lower treble peak on the S2 Pro. The BL-03 has better bass definition and better detail retrieval. It is much easier to get a good seal using stock tips with the S2 Pro. Because I need to use double flange tips with the BL-03, the S2 Pro is more comfortable. The S2 Pro comes with a more premium carry bag.
TFZ S2 Pro vs TRN V90
The TRN V90 is a five-driver (4BA+1DD) hybrid IEM. The two IEMs are similarly tuned from the sub-bass through the lower midrange. The V90 has smoother treble. The S2 Pro has slightly faster bass than the V90. The V90 has no issues with sibilance. The V90 has better clarity and detail retrieval. The V90 has better imaging and instrument separation. The V90 has a larger soundstage. The S2 Pro has worse driver flex. The S2 Pro does not hiss, while the V90 does. The V90 has a venting issue where if the inner vent is covered during insertion, the sound produced by the IEM is muffled and must be gently tugged away from the ear to restore proper clearance. The V90 has a more secure fit. The S2 Pro has more premium packaging and a better accessory selection.
CLOSING WORDS:
The TFZ S2 Pro is a good if unremarkable single dynamic driver IEM with fast, well-articulated bass. It is very comfortable to wear for long periods and comes with a good set of accessories, including a much nicer cable than other offerings at this price point. However, there are other IEMs at this price point with more refined tunings.