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About to install an amp for the first time

1203 Views 24 Replies 7 Participants Last post by  Adurm
Hey, i've got a 2019 Jetta S - great car, but base model and the sound is completely wretched. Figured this is a good opportunity to take on a little project.

I've got a pretty solid grounding in EE stuff, but basically no practical automotive audio experience beyond watching others nearby, so I have some questions about this project that you folks might know the answers to.

I acquired one of these: Soundstream Reserve RSM4.1200D
I want to initially use the 4 existing speakers, as i've heard they aren't particularly bad, though eventually i'd like to put something much nicer inside.
I've read that it's the amplifier in the infotainment that really sucks in this car. I'm not looking for masses of power - if I can get even a good sounding 50W/channel for now, that would make me a v happy camper.

So, my questions thus far:
  • There are 2 fuseboxes - engine bay and interior. The interior fusebox has some spare holes. With amp installations, people seem to run a new wire to the battery with an inline fuse. Is there a reason for this beyond installation convenience? Could I for example, add a 25A circuit to the interior fusebox?
  • All the speaker wires run to the quadlock at the back of the infotainment. Is it a reasonable approach to leave them in situ, and route new wires from those ends behind the radio, down to wherever i'm putting the amp (perhaps under a front seat)? Or is there a good reason I should pull the wires out and reroute them? (thinking about my options if I want to sell the car down the line, here).

Much appreciate any responses you have for me!
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Super stoked you got the manual. There should be another rubber capped hole up there you can poke a clothes hanger through.

If you have the glovebox brains, the quadlock i referenced should work. I think some of the newest vw have the brains but it's covered by a panel. You could disconnect the original brown piece with two small screwdrivers prying little tabs. Make you own 4 channel speaker wire leads and connect to the new brown piece to run to the amp. Then run your amp out to the original brown piece using some thin spades to plug into it. Speed wire (9 wire) would be simplist. The orm wiring is fine. I don't think the oem speakers will take more than 20w without crossing over at least 80hz.
Oh and you will need a remote turn on source. There's a fuse in the driver's side panel for the 12v cig plug. i believe it's a 20a. You can get a tap a fuse kit and run it from there. There isn't one in the quad.
Haha yeah, it's weird having a 2019 manual but it was cheap and gets like 45 to the gallon on long rides if you're gentle with it. 💰

The quad is actually right behind the head unit in this car (it's this 2019 VOLKSWAGEN JETTA DASH MOUNTED RADIO RECEIVER DISPLAY 17A035868 OEM | eBay). I'll try to find the 'purchase' button for that quadlock harness - it looks like exactly what I need, though if I can't get it I might just end up cutting the wire up anyway and try to make a good job of it.
Ya i forgot about the no glove box unit ones. The quad replacement plug should work. Please Google mk7 golf radio pinout for a diagram. Please note that things may be viewed from plug side versus harness side. Orientation can be a bit confusing. I would kindly suggest that if you do cut into the factory harness, make sure you leave enough room to reconnect it. So far I'm on install number 5 on mk7/mk7.5 golf platforms. 2 cars though. Because i keep changing my source thinking it's better one way or the other. Best audio quality is bypassing the oem deck. But you lose bt, steering wheel controls, nav commands.
One last thing, those pins are impossible (from my experience) to remove from the quad once inserted.
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