You're right, it was 10" initially - modified original thread.
The Rivian 'sub box' is pretty terrible too, we couldn't get rattle under control.
Ended up switching out JL 10 (replaced Rivian sub, unplugged).
Put a JL 12TW3 with factory box down in spare tire cavity *** no more rattle *** and...
No 12v issues thus far.
Modified LC5i to remote switch on using switched 12v wire (instead of relying on sensing) - no more turn on delay and can listen at low volumes.
The instagram reel belongs to the shop I used.
It was in a few stages, cost me around $4500 with equipment (the C3s are ~$580 alone) + install and sound deadening.
I've been a JL fan for a while and still appreciate their evolution over the years.
If you're into the search, go to a speaker...
Firstly, thanks to @redantpile for all his posts. Very helpful and motivating. I'm not the posting type but will try to respond. Hope this helps and motivates others.
Short Version:
Rivian R1S(non meridian) sound system is sub par.
Midrange is very muddy and bass is very lackluster.
I had a...