EDIT 2020-10-20: From 4.5/5 to 4/5. Surpassed by the Yincrow X6, cleaner and more fun with a MUCH better bass. Although technicalities on the S130 is better than the X6 and is still very good, but the price of the S130 makes it drop in score.
Disclaimer: I bought this at full price at my own expense. I never post links but this is a pretty hard to find earbud so here it is: https://www.aliexpress.com/item/4000858070091.html
Price: 48 usd
Driver size: 15.4mm
Frequency: full range
Frequency range: 20-20000KHZ
Rated power: 0.02W
Rated resistance: 130（Ω）
Sensitivity: 108 dB/W
Distortion: 1 TMD%
3 pairs of donut foams
Cable: It is an 8-core cable with a divider and connector made out of metal. No chin-slider and the braids aren’t very secure so it feels like it will untangle itself over time. It is a bit heavy though.
Build: Standard MX500 shell, nothing special but it is the kind of shell you get in the 0-10 usd range. So, would have liked to see a metal shell or something better than this at this price.
Fit: MX500 shells fits me so it’s good for me.
Comfort: Being an earbud it doesn’t go into your ear canal so that means that there is less physical contact between the bud and your ears. So, there is not much heat generated and comfort is very good.
Isolation: None, it is an earbud after all.
Setup: Ibasso DX160 (low gain, volume around 41), stock cable, full foams
Lows: Both sub and mid-bass quantity is high, but the sub-bass has better quality than the mid-bass due to it being tighter and therefore a bit cleaner, texture is also better. Extension is quite good but it backfires a bit (more on that later).
Mid-bass: Metallica – fight fire with fire (01:26-01:37) it is muddy because it isn’t enough tightness to keep it clean and individual strikes are also hard to hear.
Hiroyuki Sawano – pretenders (0:00-0:55) has good quantity but it is a bit loose, but fortunately not loose enough to make it muddy.
Sub-bass: Djuro – Drop that bass (01:15-01:30) the extension is quite good and rumble is definitely hearable but a basshead will want more, but the punch is very good and it is very tight and textured so that makes it really fun and exciting.
Will Spark – sick like that (03:08-03:22) really impressive texture and quantity without making the sound muddy at all.
Mids: Female/male vocals balancing is very good. Quality on both are also very high and natural.
Female-vocals: Hiroyuki Sawano – OldToday (0:50-01:20) is very soothing and beautiful while the (03:50-04:17) section is more energetic but still soothing and the S130 reproduces that without any kind of sharpness at all.
Evanescence – Bring me to life (0:56-01:36) is done really well and not sharp at all.
Male-vocals: Hiroyuki Sawano – Call your name (0:15-01:16) really good amount of thickness and warmth and it sounds very natural.
Hiroyuki Sawano – Pretenders (00:57-01:17) a little bit too warm and lacks the energy you get from a higher pitched male voice.
Hiroyuki Sawano – Scapegoat (00:13-00:57) suits it well since the thickness and warmth is really good for it.
Highs: Hiroyuki Sawano – CRYst-Alise (01:42-02:42) the violin has a lot of texture and sounds very natural
Hiroyuki Sawano – Bios delta is a bit too warmth and isn’t as clear as it should be because of that.
Hiroyuki Sawano – Lose (string version) is very well textured but is a bit too warm and makes it less energetic.
There isn’t a lot of air though and it combined with the overall warmth of the sound makes the treble not very clear. So, this affects some songs that should be energetic and clear. But it is a very natural treble.
Soundstage: Big but not that impressive when compared to other earbuds (the lack of air definitely contributes to this).
Tonality: Warm L-shape, Timbre is quite good and the sound is very natural. Lacks some treble extension and air though.
Details: Very detailed and will reveal the inferior mastered track even between the same songs just on different albums. For example, on Hiroyuki Sawano – Alive (best of vocal works NZK 2) (02:23-02:37) where the mastering of the sound just makes the overall sound muddy. While it is not on the Do as infinity – Alive (alive album) (02:23-02:37) (same song). So, if you have bad quality files or bad mastered it will show it to you in the face.
Instrument Separation: Below average instrument separation and imaging, it is hard to pick up individual instruments and position on Shiro Sagisu – Hundred years war (0:00-0:34) where the bass just makes the entire sound muddy.
Songs that highlight the IEM:
Good genres: Trance, OSTs, Jpop, pop, rock, metal
Bad genres: Hip-hop, EDM,
NiceHCK DIY MX500: The treble quantity and extension is higher on the MX500 and it also makes the overall sound brighter. MX500 have a bit more natural treble because of it having more air but the quantity can make some songs just a bit too bright to sound natural.
Female vocals are quite similar but is mostly affected by the treble, so it sounds a bit more energetic on the MX500 while it is more relaxing on the S130.
Male vocals are more natural on the S130 because it is warmer and thicker and is a bit more forward.
Mid-bass quantity is a bit lower on the MX500, but it is tighter, faster and cleaner. And individual bass strikes are more hearable. Texture is a bit better on the S130 though.
Sub-bass quantity is higher on the S130, tighter, faster and more textured. S130 also extends a bit lower and has some more rumble but pretty close.
Soundstage, details and instrument separation are better on the MX500 while timbre is equal.
I would recommend the S130 over the MX500 if you want something more relaxing and with better sub-bass. Otherwise the MX500 is a better value since it is 4x cheaper and pretty close in SQ.
DQSM Turandot: The treble quantity is much higher on the Turandot and while it does have more air and better extension, it makes it sound much less natural so for me the S130 sounds better.
Female vocals are also more forward on the Turandot, it sounds more energetic and cleaner than the S130 but it is also a bit too forward to sound natural.
Male vocals are a bit more forward on the Turandot but it is too bright and needs more warmth/thickness for it to sound natural which the S130 has.
Mid-bass quantity is higher on the S130. Speed and tightness are better on the Turandot while texture is equal.
Sub-bass has much more quantity, speed, tightness and texture on the Turandot and also extends, rumbles more.
Soundstage, details and instrument separation are better on the Turandot. But timbre is better on the S130.
My recommendation goes to the S130 and that is because it sounds more natural and is more relaxing while being much cheaper.
Conclusion: The S130 is a very natural, relaxed and warm sounding earbud. I recommend it for those that seek that kind of sound, while I do not recommend it if you want a brighter and airier sound. Thanks for reading.