I've told you a month ago that I received the Kiwi Ears melody. On short, that's my impression on it compared with the S12Pro: https://www.head-fi.org/threads/kiwi-ears-melody-12mm-planar-universal-iem-thread.970554/#post-18085600

I got my Melody more than a month ago. I already had the S12. First impression was that they sound the same, but it was that song only. Melody has sibilance S12Pro doesn't. S12Pro has better and deeper bass, faster and more layered. Melody has a strange extended bass - like a DD, more mid-bass...

Looks like a brick to me... Sorry, but I don't like sharp edges.

Have you done a serious burn-in ? Because from my experience with Burson Op-Amp's they change a lot the sound after few hundreds of hours.

The problem is that after you polish them according to your needs, everybody else will complaint about...

Now that you mention these...

I had this mod in mind when I bought them, but in the end I didn't need it. There is only one player I have where there is too much treble - the Hidisz AP80 Pro - somehow this one sound quite neutral with the S12Pro, with less bass, but with a bit of extra treble. So I use them more with the...

That's what I said few pages ago - they sound very different depending on the source - on some there is too much bass, on others too much treble... If you pair them well, there is no need for modding.

Interesting, because this doesn't exist yet on the Topping website... Only D50s. Wonder if this one has replaceable OP-AMP in the buffer.

There are tastes and tastes... I consider the Pro better and also think it still has a bit too much treble :D But yeah, people bought more the OG - cheaper and more long time on the market. Also, I'm not sure, but there were some problems with QC and suppliers when the Pro launched - that could...

The I/V stage makes the biggest difference. So, the Dual OP-AMP's...

Ok, it seems Burson released them for sale. Quite expensive... https://www.bursonaudio.com/shop/supreme-sound-opamp-v7pro/

I guess the other two are part of the amplifier, so they don't make a difference or only very subtle. I/V change about 70% of the sound, the buffer perhaps 29%. So the rest maybe 1%. The main problem for the moment is to get the V7.

Now, it seems that I have completely opposite problem than yours. I feel the tube is too long, and the nozzle diameter is too big so they don't get in my ear very well - they stay at few mm outside my inner ear. Luckily the hook radius helps me to keep them in place, using small memory foam...

Biggest changes will be when you change the I/V op-amps. You can try with 4 - 2 Vivids and 2 classics - and see what combination you like. Put 2 Vivids in I/V and 2 classics in Buffer/Pre, then switch between them.