I'll put it plain.
At 10$, this is the best pair of earphones you can buy.
A4 Tech MK 620.
The sound is extremely clear, bass is deep and well defined.
Not even my 20$ Sony MDR-E11LPB sound better than the A4 Techs.
The only bad thing to say about the A4 Tech earphones is that they aren't very durable, the cable breaks (near the jack) pretty fast (~2 months) if used for portable applications.
So if you are very low on budget (like I always am), consider these 10$ earbuds, or earphones similar in quality (with a more solid bass response), A4 Tech MK 320
-the cable isn't very durable
-if you wanna mix in them, keep in mind that the high frequencies are a bit boosted on these earbuds
-probably look a bit cheap, nothing fancy
-extremely good sound and frequency response overall (goes down to ~26 Hz, tested that myself)
-comfortable, both of them (MK 620, MK 320)
I haven't tested a lot of headphones, since I'm always low on budget, but these are by far the best ones I've got.
I still have a pair of them (with a changed cable though) and use them a lot, for mixing too. (yeah yeah, I know, not professional, but I don't really have a better alternative)
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