If it’s “
BASS” you’re after then you won’t get more nor better than the Fat Freq HBB Deuce for under €230 , I have a pair of them and they have more than enough sub bass to rattle my teeth with my electronic music listening, add the included impedence adapter and the bass just gets silly, I’ve never felt the need to use the adapter btw.
I’ve not listened to mine for a while as I have other iem’s I prefer,
The Deuce is a dual-dynamic IEM using FATfreq's 2nd generation Basscannon technology: 25dB sub-bass shelf, expertly controlled under 150Hz. Tuned in collaboration with Bad Guy Good Audio Reviews (HBB), the Deuce excels in dynamics, capturing both subtle and powerful moments with ease and giving...
hangout.audio
Edit : just noticed you mentioned amazon for purchase.