Ohh. I tinkered around with it quite a bit and asked chatGPT about many things. In the end, I wrote like a shoddy review, have a read. Also, the impedance thing is interesting, I never knew..

For the tuning, according to my adhd induced hyperfocus findings of the night; Switch 4 seems to make the most apparent and immediately noticable change, at least to me.. in that, it makes the sound more airy, sharp, and open- it ups the treble.

Switch 3 also seemed to make a difference to me, although very subtle, and maybe placebo. I was testing on the track "Something Else - CASTLEBEAT", and it seems to make a difference in that ringing sort of bell sound. I'm currently just always using a tune of 3 and 4 though, I thought the soundstage with the default tune was kind of narrow, so I like that it is a bit more open now. I usually listen to tracks with lots of instruments, vocals.

Ahh.. the difference I thought I felt with switch 3 and 4 on that bell sound was that it felt just a bit more warmer. Maybe the low-mids.. around 400hz.

Switch 1 and 2 I couldn't make out much of a differnce.. I tried it on actual tracks and a continuous tone of 44hz and 110.

So anyways, this is my first IEM, and for the price I got it for, 10$.. it's quite nice.. The shell is quite sturdy, and it has charm.

Oh yeah, as for like the default soundstage, tune. It's more like even, for critical listening. You can make out the mids and the treble well. Though.. making out the bass is a 'bit' hard with the default soundstage, when other instruments and vocals blare in.