Hi. I've got a JBL green edge car stereo system fitted in my plug in. What's the best way to get a stereo RCA output for a bigger power amp to run some much bigger speakers and a sub in the back? That's if it can be done?
You'd need to find the amp and see if it even has outputs, it may not. But many decent amps can use speaker-level inputs. Or, you could remove the JBL and swap in another.
As indicated above it would be easier and cleaner to get an amp that would accept speaker level inputs and then outputs higher power to new speakers and subs. If you already have an amp that does not do that then get one of the speaker level to rca converters. Some are 2 in 2 out others have 4 in 4 out. The four channel units would allow your jbl front rear fading to work. Line Output Converters at Crutchfield.com