im just taking a guess, but low level could be because the signal is not amplified, and its just 4 volts( depends on deck) and high level because the signal (takin from head unit output) is amplified. The rca's have way better sound quality....
97 V6 ATX 20,000 Miles
alpine cda 9811
Alpine MRV-F357
hifonics brutus BX2000D
2 Kicker L7 15
I NEED GREY LEATHER DOOR PANELS!!!!!!
Flip out monitor
PS2
Spr-175a
SPR-69LP
SPR-57LS
60 Ft EDEAD