Is この refering to サウンド or 中二心? How does に and an intransitive verb work
together? My translation attempt is: What is this sound that resonates with my
chuuni heart?
CC BY-SA 4.0
2018-11-15T21:43:00.007
62861
2018-11-17T03:06:23.317
31844
question
syntax particle-に
何だこの中二心に響くサウンドは Does この refer to サウンド? How does に and an intransitive verb work?
この refers to 中二心. The に tells you location where 響くis happening.

A reasonable translation would be: What! The sound that resonates in this
chuuni heart...
CC BY-SA 4.0
2018-11-16T02:01:08.450
62864
2018-11-16T02:01:08.450
10045
62861
answer
> Is この referring to サウンド or 中二心? How does に and an intransitive verb work
> together? My translation attempt is: What is this sound that resonates with
> my chuuni heart?

The この refers to サウンド. The basic structure of this sentence is 「何だ、このサウンドは？」
(= Inversion of 「このサウンドは何だ？」, "What is this sound?")  
The に is an indirect object marker. 響く is an intransitive verb and can take an
indirect object.

「サウンドが心に響く」 = _lit._ "A sound resounds/echos through one's heart" → "A
sound/tune/music resonates with / touches one's heart"

So I think your translation is good.

> 「何だこの中二心に響くサウンドは（？）」  
>  "What is this sound/tune/music that resonates with / touches my chuuni
> heart?"  
>  (... with a nuance of exclamatory "What a (touching) sound/tune/music this
> is!")
CC BY-SA 4.0
2018-11-16T02:52:52.857
62866
2018-11-17T03:06:23.317
2018-11-17T03:06:23.317
9831
9831
62861
answer