Build Quality
The build quality is quite good. Depending on the light, the faceplate’s blue color will change from dark to light blue. The only minor issue is that the case color will change from black to purple under Sunlight.



Isolation
The Isolation is quite suitable for hybrid — one of the best I experienced. If CIEM without vents isolates for 10/10, Fan 2 isolation is around 6.5/10.


Comfort
Comfort could be tricky. Fan 2 has an extended nozzle. I personally feel uncomfortable when I insert universal IEM deep into my ears. I prefer a shallow insert, and Fan 2 sticks out of ears with a shallow insert.



Stock cable and brief cable recommendation
The stock cable enhances Fan 2 sound signature. It extends highs and increases the presence of mid-bass, making the bass more tactile. However, it also increases the upper-mid sharpness, making a sound less warm and less balanced. The tonality of the cable is close to the SS-47 solder combination with the OFC cable.
Changing the cable can make the sound more balanced and closer to neutral, but you will lose the musicality, tight bass, and energetic upper-mids. I recommend an OCC cable with lead-free solder that doesn’t contain silver may result in the best combo that compensates for the balance with minimal losses in the original tonality of the stock cable.



Burn-in Experience
At the first listening experience, Fan 2 sounded mid-centric, with quite prominent upper-mids. After around 50-60 hours of burn-in, bass stars began to appear. After around 100 hours of burn-in, sounds become more balanced with bass, mids, and high with equal amounts.



Sound descriptions
Fan 2 sound signature is balanced and mild W-shaped, where bass, mids, and highs have the same dB rawly. Timbre is natural, more on dynamic driver type of presentation with slower decay. Fan 2 sounds cohesive from top to bottom, like a one-dynamic driver IEM. Fan 2 sounds remind me of a combination of the “reference” tuning house sound of the Singaporean AAW brand, a “musical” type of neutral tune, combined with Harman-ish tuning due to its upper mids.
The bass is linear, with enough sub and mid-bass presence to hear and enjoy all bass notes and texture. The bass is slightly boosted compared to the neutral tuning. Mid-bass quantity is on the verge of being boomy and remarkably balanced to give a slam and the punch. Sub-bass has a good texture and speed, not the deepest but tight. The bass is still not in the good BA speed territory. Sub-bass present may feel not enough compared to the more “Harman” and V-shaped tuning IEMs. But if you are willing to hear the bass correctly without missing any texture, Fan 2 tuning is done right. Bass is more like on speaker with a good woofer rather than with a subwoofer. Despite that, Fan 2 is not a Bass-head IEM, the bass is still a star of the show, with its quality and quantity quickly satisfying for bass lovers.
The mids are just slightly forward compared to the neutral-tuned IEM. The mids have excellent technicality, without being harsh, slightly smooth and analytical, and have the same speed and decay as the bass, never sound shouty. BA detail retrieval is good, but nothing outstanding.
There is a slight presence on upper-mids or lower-high around the same level as “Harman” tuning IEMs but sensitively more compared to “true” neutral-tuning IEMs.
The highs have good quality, smooth, and very safe from any discomfort. The 7kHz peak adds a nice shimmery to the sound, but I wish this peak were around the 8-10kHz region. Highs are not well extended, so you don’t hear much after 10kHz, and for some, Fan 2 may sound dull.
The soundstage is the second thing that impresses me, except for the bass. Fan 2 sounds like an excellent dynamic speaker. It lacks an excellent instrument separation that could give a 3D holographic effect. However, the soundstage covers a good fraction of the headroom to immerse in the music.
Fan 2 has a minor drawback, at least for me. Their dynamic range of BA drives is shorter than I usually prefer. I believe that to fix the BA harmonic overtone pitch problem, they shaved the BA higher pitches and increased loudness, similar to how dynamic normalizer work. This led to dynamic range shortness, which feels especially on vocals. Despite that vocal has good details, they lack an emotion that gives an excellent dynamic range.


Source recommendations
A Neutral or slight U, V-shaped source may work best with Fan 2.



Comparison

Penon Fan 2 vs. 7hz Zero
Zero is one 10mm budget IEM vs. Fan 2 is 2x6mm DD and 2xBA hybrid IEM.
Zero has more sub-bass that is deeper and less boomy but slower. Mids have a better balance, and highs are more crispy and sharp. Fan 2 sounds more aggressive on upper mids and less warm on mids.
Soundstage has a similar presentation with up to 3-4 times less headroom. Instrument separation is slightly better on Fan 2.



Penon Fan 2 vs. Tinhifi T3+
I don’t have Tinhifi T3+ and Fan 2 with me simultaneously. I will make a comparison by my memory. Take this comparison with skepticism.
T3+ is 1x10mm DD IEM vs. Fan 2 is 2x6mm DD and 2xBA hybrid IEM.
There is a lot of sub-bass and almost non mid-bass present on T3+ compared to the Fan 2. Lower mids are recessed, upper mids has around the same presence on T3+, and highs more on T3+, compared to Fan 2, which sounds harsh. The bass is slow and lacks any texture. The soundstage is almost double as smaller on T3+ but with the same presentation style.


Penon Fan 2 vs. VE SIE
SIE is 1x10mm DD IEM vs. Fan 2 is 2x6mm DD and 2xBA hybrid IEM.
SIE on the graph looks like a V-shaped, in reality, it sounds nicely balanced W-shaped with a bass boost. SiE is also transparent and may sound differently from source to source.
SIE bass sound more bloated compared to Fan 2. It even feels that the bass is bleeding to the mids, but it’s not, SIE loses time-to-time control over the bass that gives such a feeling. Quantity-wise, SIE has much more bass than Fan 2, However, the bass on SIE is slow and doesn’t have a good texture.
Mids are warmer, thicker, and smoother on SiE but still cold and analytical due to increased upper mids. Mids have slightly less forwardness. Although mids on SiE are not detailed like on Fan 2, I like mids on SiE more due to better dynamics.
Highs are more extended on SiE with better shimmery, with the same safe type tuning, but the quality is like on most DD.
SiE has a peak on upper-mids that may cause a sibilance on some female vocals or make old-school mastered metal music guitar sound too forward.
The soundstage is almost the same, Fan 2 has better instrument separation.



Penon Fan 2 vs. Xenns Madrid Tea 2
I don’t have Xenns Madrid Tea 2 and Fan 2 with me simultaneously. I will make a comparison by my memory. Take this comparison with skepticism.
Tea 2 is 6BA + 1DD Hybrid IEM vs. Fan 2 is 2x6mm DD and 2xBA hybrid IEM.
Tea 2 has slightly more sub-bass, and the mid-bass is less in quantity. Tea 2 doesn’t have the same texture as Fan 2. The speed of Tea 2 bass is also slower. Mids are slightly more present on Tea 2. I would say that Tea 2 has a better mid quality overall, smoother and more pleasant to listen to, especially can be noticeable on vocals. Highs have the same safe type of tuning but are more extended and more lively on Tea 2. The soundstage is equally good, but Tea 2 sounds more holographic. Tea 2, of course, is not cohesive as a Fan 2. Tea 2 sounds like a hybrid with slow DD and fast BA, while Fan 2 sounds like high-quality DD. Overall, I would say they are at the same technical level with their drawbacks.


Penon Fan 2 vs UE RR (CIEM)
While there is a big gap between them in price value, they are worth to be compared since they are both closer to each other by tuning. There is also a big gap between them in release date, 2016 vs 2022, so it will be interesting to compare technology-wise.
UE RR is 3BA CIEM vs. Fan 2 is 2x6mm DD and 2xBA hybrid IEM.
The first noticeable thing is that even the RR sound is still natural as Fan 2, without any BA artifacts, with timbre closer to the DD, Fan 2, in comparison, sounds slow and colored. The lower mids are missing on Fan 2, bass with upper mids are noticeably presented, and mids sound dry on Fan 2.
Both have linear bass, while RR bass doesn’t hit hard as Fan 2 and is more neutral. However, the speed and texture are better on RR. Fan 2 bass sound muddy in comparison to RR’s.
Mids on RR are neutral, smoother, warmer, with good dynamic range, and both male and female vocals are more emotional.
Highs are more extended on RR, it has the same safe tuning as a Fan 2, but it extends so well that you don’t miss any highs up to 20kHz. The highs also are more crispy and smooth on RR.
While headroom on Fan 2 is almost the same as on RR, there is a noticeable gap in instrument separation, RR sounds more holographic.
Because Fan 2 has more forward upper-mids, detail retrieval on Fan 2 at first glance may look better. However, if look to complete frequency response, Fan 2 falls behind.
If Fan 2 sounds coherent and can be listened to for hours without stopping, RR amplifies this concept multiple times.



Penon Fan 2 vs AAW W500 Ahmorph (CIEM, stock tuning)
While there is a big gap between them in price value, they are worth to be compared since they are both closer to each other by tuning. There is also a big gap between them in release date, 2015 vs. 2022, so technology-wise, also it will be interesting to compare.
AAW W500 Ahmorph is 1x9mmDD and 4xBA CIEM vs. Fan 2 is 2x6mm DD and 2xBA hybrid IEM.
Both have a slight W-shaped signature closer to neutral and are close to each other by timbre. The hybrid timbre issue on W500 is not noticeable at stock tuning because of low and high-frequency sound by DD and mids and highs with BA, which intercept with DD for more coherent sound. In other words, DD that uses AAW for W500 is not used only for bass, and you can even turn off BAs completely by its tuning nob.
The first noticeable thing is that the W500 bass is in another league. While it is not increased as on Fan 2, it hits harder and extends crazy low, like a real big subwoofer. Fan 2 defiantly has more sub-bass and mid-bass present. However, it is like comparing a 6-inch subwoofer with a 12-inch subwoofer. Considering that W500 has a full-range 9mm DD, and Fan 2 2x6mm DD for bass, the quality of DD on the W500 is noticeably better. The echo that generates W500’s bass creates an excellent 3D image, like sonar radar.
W500 mids are less forward but still not neutral. Mids peak at 1.5-2kHz on W500 and can have sibilance on male vocals, especially noticeable in Hip-Hop music. However, lower mids are missing on Fan 2 in comparison. W500 sounds thicker, warmer, and smoother, even though technically, mids are close in quality.
Highs have almost the same tuning as on Fan 2. Same 7kHz peak but is more extended with still laidback presentation as Fan 2. And when music has good extended highs, W500 is a pleasure to hear.
The soundstage feels noticeably bigger on W500 due to its bass and more extended highs. Even though the sound signature is W-shaped, the bass fills so much headroom that the sound starts to feel that you are listening to are good L-shaped IEM.
Since Fan 2 has more forward upper-mids with more prominent presence, detail retrieval on Fan 2 at first glance may look better. However, if look to complete frequency response, Fan 2 falls behind.




Music Recommendation
Despite almost all music sounding good with FAN 2, some stand out. For such sound signature, the best music that comes to my mind is multi-instrumental electronic music, such as Movie and Games Soundtracks, IDM, Dance, House, Disco, Contemporary Electronic, Trip-Hop, Experimental Electronic, and Electronic with Ethnic and Live recordings, Industrial Electronics, almost all electronic music, even including the Ambient.
Jazz, Rock, Nu Metal, Alternative, some Metal, and classical music sounds all right. However, I prefer warmer and more organic-sounding IEM for such genres.
I personally found that with its timbre, it sounds best for chilling with the slower type of music.












While this music sounds not bad, I don’t recommend buying them for Dubstep - prominent upper-mids can be a problem. Some Modern Metal - 6khz dip makes on some masterings lead guitars stay behind everything else with insufficient presence, and mids are not warm and smooth enough for guitars, in my opinion.














Recommended for
Fan 2 is recommended for some looking for a versatile, cohesive, safe reference type of tuning with extra energy on upper mids. They are well-tuned, and they can be used for long listening sessions. Fan 2 has a good balance between being analytical and musical.

Package
Penon TAIL comes with a high-quality leather punch and with optional cables. The punch is lovely, pocketable, and protects the Tail from scratches. There is enough room inside the punch for both the Tail and cable.



Stock Cable
The stock cable is flexible and slightly longer than the other cables I have from the other Dongles. The cable doesn’t add any extra signal interference. The sound signature of the stock cable is more oriented to the highs, with a slight emphasis on upper mids and smoothing the highs, while the sound gets extra refinements on mids and sub-bass. However, lower mids have a slight dip, and mids sound dry and analytical.


Sound
3.5mm vs. 4.4mm output was compared using the Ultimate Ears Reference Remastered CIEM with two DIY cables, both 3.5mm and 4.4mm cables have the same resistance, cable structure, and soldering.

The Tail’s sound signature differs from 3.5mm and 4.4mm output.
3.5mm output is neutral and almost linear without noticeable peaks and dips. But mids are still slightly forward.
While 4.4mm is still close to the neutral, it is balanced with a slight emphasis on the sub-bass. Highs are neutral, smooth yet nicely extended. Mids on 4.4mm are even more forward and bass softer. Tail is not an analog-sounding or NOS-turned-on type of. I hear a noticeable oversampling processing that adds to the extra sound refinement. Nevertheless sound more digital, especially from a 4.4mm output.


Comparison
All dongles are compared using the same type-c cable and 3.5mm output, using the Ultimate Ears 18+ CIEM and Macbook Air M1 as a source.

Vs. iFi Go Bar
Compared to the Tail, iFi Go Bar with a Red filter has a neutral sound signature, and mids are closer to neutral without being forward. iFi Go Bar has more linear bass and a warmer sound. Both lows and highs are more extended, and highs are more smother. However, iFi Go Bar with a White filter comes close to the Penon Tail sound signature, and the only difference is that Go Bar is smoother and one step more mature sounding. Soundstage presentations between them are close, while with iFi Go Bar is as if you are staying an extra couple of feet away from speakers. Sound quality-wise, I have not heard a big difference with IEMs under 300 USD, and they differ with more high-end IEMs.
If Apple Dongle is 0% and iFi Go Bar is 100% in SQ, I will put the Penon Tail at 65-95% (depending on the headphone class).

Vs. LP W2
LP W2, with filter Fast and tune 2, has almost the same bass and mids tuning as the Penon Tail, except the upper mids and high are smoother on W2. Highs on 8-10khz are more increased on W2 and have extra crisp. Both lows and highs are more extended on W2, and the soundstage is more 3D holographic due to more precise instrument separation. Luxury & Precision has one of the best highs on the dongle market, which may give an illusion of more high-quality sound and better soundstage even with mid-tear IEMs. In reality, it just has a different type of soundstage presentation. Penon has closer to near-field soundstage rendering, while W2 is more mid-field.

Vs. Sony WM1A
How does it sound compared to the Sony WM1A? I honestly believe that It is incorrect to compare both of them since WM1A sound signature can be customized with third-party firmware. Most importantly, comparing the Sigma DAC with proprietary Sony FGPA sound is unfair because both have their own strange and weaknesses. Sigma DAC may sound more 3D than Sony with studio recording. However, Sony is a benchmark for me for bass texture, details, timbre, and Tail can’t come close.


Cable synergy
The stock cable emphasizes well Tails sound signature. However, I still need more warmth.
I like how Tail sounds with iFi Go Bar stock cable, which adds extra warmth and smoothness to the mids.
Another cable I like with Tail is the stock cable from Lotoo Paw S1, which makes the sound better balanced and warmer. However, the upper mids are not smooth enough for my liking.
LP W2 stock cable has the best balance, is closer to the neutral sound signature, and matches well with the Tail.


Headphones synergy
If you are upper-mids or mids sensitive, I will not recommend using the Tail with W-shaped, neutral, or mid-centric IEM with 4.4mm output. While my UE Live has buttery smooth mids, yet mids sound too forward. AAW W500, with its 1.5khz peaks, makes mids sibilance. Overall, slight V-shaped IEMs/headphones will be a better choice. At the same time, 3.5mm is pretty much listenable with any headphones signatures.




Amp. Power
The most power-hungry headphone I have is a DT770 80ohm modded for a balanced connection. Testing from MacBook Air M1, Tail handles the DT770 with a high gain at 40% listenable volume, while iFi Go Bar with IEM match-off with 55% volume. I do not hear bass loss or highs becoming too sibilant. That means that somehow DT770 is getting enough power from Penon Tail. Connecting the Tail to the iPhone with DT770, I need to increase the volume to 55% volume to get the same listenable loudness. I did not notice any difference in the sound quality between Macbook and iPhone with Tail and DT770. When I connected Go Bar to the iPhone, using the DT770, I noticed the sound quality decreased compared to the Macbook. DT770 sounded with less bass, the soundstage became less, and the highs hotter. DT770 sounded better on Penon Tail from iPhone than on Go Bar, while with Macbook was the opposite.


Power efficiency
Penon’s engineers did a fantastic job optimizing Power efficiency. For example, Tail will not drain any power if you disconnect the headphone. When the headphones connected and no music played, the dongle switched to the power-saving mode. Also, I was impressed that Penon Tail keeps the voltage constant with iPhone, which means that SQ with iPhone compared to the Android and Desktop sources should not suffer. Here are some measurements that I did with the Charger Doctor and Apple Camera kit Adapter:



Conclusion
Penon did a fantastic job making the great dongle that sounds good and power efficient. The Tail is not an ideal dongle. However, it is competent and can stand out even at a higher price by its sound quality. Overall, I enjoy the sound of Penon Tail, equality as from iFi Go Bar, and LP W2. Most importantly, using iPhone as a source, Penon Tail gives almost the same sound quality as dongles that cost more than three times, and thanks to its power efficiency, it can even outperform my favorite dongle with more power-hungry headphones.