Pros: 1) Wide soundstage
2) Upfront, Bold and Dynamic Sound Signature
3) Great with orchestral music and bassy pop songs
4) Details
5) Great cable for the FD3 Pro
6) Lots of useful accessories in the package
Cons: 1) A bit uncomfortable to wear (personal)

To Note : My review is strictly for Fiio FD3 Pro and strictly based on my use with Hiby R3 Pro Saber DAP. FD3 Pro was brought with my own money and hence the review is completely my own unbiased thoughts

I have recently brought a Fiio FD3 Pro and paired it with Hiby R3 Pro Saber Dap (through 2.5mm balanced port).

The sound that came out of the FD3 Pro through my set up was big, bold, energetic and detailed to keep it simple . I used the stock red tubes with small vocal tips and also tinkered a bit with MSEB tuning in the Hiby. However, I never touched the equalizer.

The mids of the FD3 Pro (through my set up) was forward, warm and lush. Bass was punchy and strong but never overpowering the other frequencies . The treble was smooth yet still detailed but not sibilant. Some of the best music I enjoyed through the FD3 Pro were music with large amounts of instruments (orchestral music mostly) and also energetic pop songs. Soundstage was more wide than deep and I could easily distinguish between extreme left, left, centre image, right and extreme right. Imaging within the soundstage was also pretty good.

Edit: I tried the black tuning filters. They made the sound too bright for me

Some tracks I listened to
1) AR Rahman music (Mudhalvan, Alai Payuthe, Jeans etc)
2) Durum - Kate Linn
3) Casanova- Allie X
4) Beat the Devil's Tattoo - BRMC
5) Animals - Maroon 5
6) Sgt Peppers Lonely Hearts Club Band - Beatles

My MSEB settings for Fiio FD3 Pro
Bass Extension: +15
Bass thump: +10
Note thickness: +10
Vocals : +10
Female Overtones : +15
Air: +15

New mid tier iem from fiio
Build quality and accesories package 5/5
Fit/comfort 4/5
Modular cable 5/5
SOUND
Black filter sounds best, the stock red filters make the sound aggressive and has some bass bloat,treble is lacking. Changing to black makes the bass controlled, fast, crisp and accurate, with significantly better treble response.
All frequencies below are WRT black filter
Lows : well controlled, great kick to subbass, fast, accurate 4/5
Mids : good texture and layering, not the best point of this iem but very good for the price 3.5/5
Highs : airy, sparkly, non sibilant, crisp
Soundstage : semiopen design, excellent especially wrt form factor 4.5/5
Imaging 3.5/5
Isolation : pretty good 4/5

Very difficult to beat at this price point especially if you enjoy single DD iems.
The timbre of the sound is very musical, coherent.
Definitely benefits from amplification/better sources.
The overall package with all accessories is value for money.

I own KZ ZS10 pro, Samson SR850 with Fiio BTR5 and now this Precious Gem 💎.

Burning this FD3 Pros last few days, they are still getting better day by day. Using them with balanced interchangeable pin. Didn't like the balanced and bass eartips, sound difference was noticable just were not comfortable for long time. Vocal eartips are way more comfortable and sound quality overall is good too. Red ring nozzle kind of increase the soundstage for me, but black ring nozzle was better in every other way, with decent sound stage too. Following are my observations:

Pros :
1. Base quality is way better than previous equipment i have.
2. High frequencies are rolled off, ssses and tees are pleasent to hear.
3. The semi open design feels like you are not listening to an iem, they feel like my Samson SR850s(with replaced extra confy earpads !) Yes there is lack of proper isolation but it is worth it.
4. They look just ❤️, build quality is awesome.
5. Sound fidelity is great. You can hear the room if recording is good enough. That should suffice for audio quality.
6. Love the case too.
7. Classical music sounds noice through them.

Cons :
1. Some amount of Microphonics from cables, which i didn't thought would be the case with such expensive iems.
2. I have big ears, but still sometimes the part of iem where there is mesh to make them semi open touch my ears. For people with mid size or small ears, that could cause issues.
3. The base and balaced tip material is weird, my ears start itching in 20 to 30 minutes.
4. Imaging is slightly less good compared to other aspects.
5. The all metal body gets chilly in cold weather, just warm them up before plugging them in your ears.
6. Rarely shouty.

I would not suggest to get this as 1st iem, try some cheaper chifi options to get familiar with high res audio. If you can hear the difference in audio fidelity, and crave more of it, then sure, just go for it.

It's a really nice pair of IEMs. I have no complaints when it comes to sound or build quality. It exceeded my expectations in every way. The only real problem I have with them is that they just a hair too big for me, so I am unable to keep them on for an extended period of time without discomfort.

Extra Mid Bass and thumphyness and sufficient treble (after 5-6 hrs burning) makes exiting for starters like me....will burn more time and update any changes...tried vocal and bass eartips which are not good...it has very good build quality and looks beautiful. using with BTR5 DAC. Android blootooth aptx codec perfect combination. Vocals did miss on the back of huge thumphyness but i love that. This is for them who require V shape sound signature with good built quality and interchangeable cable, if someone doesn't want this kind of cable I would say FH3 would be much better than this...i would upgrade myself to hybrid sometime down the line...thanks headphone zone for providing quality set and on time delivery.....

Sorry mujhe iem ki jada technical knowledge nahi hai isliye yeh review jada technical na hokar BY FEEL hi zada hoga.
main music phone par hi sunna pasand karta hun.main iphone 12 pro use karta hun n ussi hisaab se yeh review hai.
Fd3 pro se pehle maine fh3 try kiya tha but mujhe uska bass pasand nahi aaya thora flat feel hua.sath hi usme vocals n treble bhi kafi high laga jiski wajah se maine usse exchange karana hi theek samjha.
Thn uske badle maine fd3 pro order kiya.n literally isse use karke meri aatma tript ho gayi😊.
2-3 hrs ki burning ke baad phone par hi bass kafi punchy feel ho raha tha.treble n vocal bhi kafi smooth feel hua.
Sound bhi thora wide hai jo mujhe kafi acha laga.n jaise jaise main isse use kar raha hun uska sound aur bhi zada acha hota ja raha hai.
Almost 4-5 saal se sennheiser cx 300 ii use kar raha tha jo mere favourite the n unke kharab hone ke baad kafi pareshan bhi raha coz jo mujhe chahiye tha woh nahi mil pa raha tha but ab finally mujhe ek aisa earphone mil gaya hai jo sennheiser cx 300 ii se bhi kahin zada acha hai.
Abhi yeh iem liye jada din nahi hue hai is wajah se main iske sath aayi eartips use nahi kar paya hun.jo black normal eartips unme lagi hui aayi thi yeh review ussi par based hai.
Aur main headphone zone ka bhi thanks kehna chahunga ke unki team ne mere sare confusion door kiye n ek acha iem lene mein meri kafi help ki
Sath hi mujhe jab exchange karana pada tab bhi unki team ne kafi
co-operate kiya.uske liye bht bht shukriya👍👍👍
Finally jaisa mujhe ek earphone chahiye theek waisa hi mujhe mil gaya hai.

Had used Fiio F9 pro before this. It was best in sound and fit. Now this is the best. Best as in my experience.