Blon 03 Re Colouring Sound Mod 3

Blon-03 Re-Colouring & Sound Mod

The famous Blon-03s. You know the story. In a nutshell, the most suggested budget IEM for beginners in the community. Compared with much more expensive IEMs, had many fans, and still have. Although Blon came up with different models later like 05 and 07, none of them caught the attention like the 03s.

Blon 03 Re Colouring Sound Mod

The nozzle length of the Blon 03 is short and because of that people had fitting problems. It’s also very slippery because of the coating so some silicone ear tips also slide down onto the shell. The cure for that is to put a spacer at the bottom of the nozzle, some cut and put the inside of a silicone ear tip for that, some found other solutions, mine was a simple 3M tape mod.

Blon 03 Re Colouring Sound Mod

The other problem was, at least for me, Blon 03 was shouty as hell. Electro guitar solos, high octave voices, like Freddy Mercury, were so fatiguing for my ears (5K peak they call it?), that I put them aside and moved on to the next IEM. Until yesterday, I decided to mod the 03 that I got some experience lately in modding, or should we say metal working ­čÖé

Blon 03 Re Colouring Sound Mod 4
Sneak peek inside

Now here comes the part why I decided to write this article/guide. After I started to Dremel-sand one of the shells and waited for what the colour of the metal will turn to, the most unexpected colour came to life, bronze. I thought to myself maybe Blon made the shells from brass? After some more sanding, some of the parts of the shell turned to bare metal colour, but some parts remained the same. Maybe Blon made some mixed metal moulding? Or maybe it was just two layers of coating so I stopped to sand deeper. Because I loved this colour so much. So sexy, so retro and unique ­čÖé

Later on, I decided to leave one of the faceplates in its original colour but changed the inside part to bronze with sanding. For now, I loved the different look and stopped re-colouring.

About the sound mod, to tame the harshness and also to make the bass more open and tight. Actually, this mod is one of the classic methods. Put a light density foam in the nozzle. Sometimes you remove the foam from the nozzle (if there is any, some brands use this tuning method) to change the sound. I have done this to my Hifiman RE0 a decade ago.


You can fine-tune the sound with the length of the foam for your taste. Longer (more) foam = more tamed sound for high frequencies. For lows, it can be tighter but also can be boomy, depending on the original tuning. For Blon 03 removing the nozzle mesh filter, and not putting it back, with a foam filter inside is the best result, for my taste. It really sounds like it should from the beginning.

Blon 03 Re Colouring Sound Mod 13
Best ear tip for Blon 03, Spinfits with a narrow inside length which sits and holds perfectly. Also sounds best I think.

Does the Blon 03 sound good after the mod? Yes. You can still count it for the best budget IEMs for around the 50$ mark in 2022. Does it sound like a 200$ IEM? No ­čÖé

So how does it look? Should I re-colour the right shell too? Or leave it like this?

Blon 03 Re Colouring Sound Mod 1
Cable from Whizzer HE03D fits amazing with bronze colour parts

Thanks for reading.


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