Details of my Upcoming Stereo Upgrade

I upgraded my daughter's 99 Jetta speakers/amp for her Christmas present. OMG, it sounds like a concert in her car. So I have decided to do an upgrade from my present set up in 996. After doing a lot of research on here, this is what I will be doing: 6.5" Polk Audi speakers in the door 8" Alpine Subwoofer in custom enclosure Some new dash speakers which include 4.5" and 1" speakers JL Audio 5 Channel Amp After doing research on amps lately, I found that JL offers a relatively high powered amp in a very small package. It is 10.5" x 7.25" x 2". I haven't set it where the CD changer goes, but my initial measurements show it will fit there. I no longer have the CD changer hooked up. It is 75w x 4 into 4 ohms (dash and door speakers) and I will be running a 2 ohm sub, so it has a 300 watt rating at 2 ohms. Somebody here upgraded the door subwoofers to the 6.5" DB651s Polk Audi low profile speakers (I also put four of these in my daughter's Jetta, and they sound amazing with the amp I put in). You just trim the existing opening and they fit right in. I had previously bought some replacement speakers for the 4.5" dash and rear speakers, but I will replace the dash ones with something of better quality with a cross over and 1" tweeter. I removed the tweeter from my system previously. For the sub, I bought an Alpine Type R SWR-8D4 1000 Watt 8" Dual 4 Ohm Subwoofer. You can hook the two coils up in parallel to make a 2 ohm speaker which gives you the 300 watts out of the 5th channel. I will make a custom enclosure to go behind my rear seat, it will be sealed box. I bought some grey carpet from a 996 on ebay and will cover it with that. The wiring will be pretty easy, just put the amp in the frunk, use the existing wiring for the doors and will need to run three new speaker wires into the cabin, two for the 1" tweeters and one for the sub. It will probably be months before I make the box and then do the upgrade....but thought I would share. Only because I like you guys.....well, some of you guys. Actually, only a few.....

Following, as this will be my summer mod project.

I've been able to get parts pretty cheap, and now looking at the speakers I have installed in the dash again, I think I will just do the upgrade and keep them in there. I bought speakers from Diablo when he parted his car out, they are JL Audio C2 400's. BTW, I plan on driving the 996 down to Daytona in two weeks, going to be there for four weeks starting two weeks from today....maybe we can get together along with DB Joe!

I am having some work done in three weeks. Don't want to hijack your thread, but let me ask this question From what are you upgrading? What is your existing system?

Sounds good, have been a JL Audio fan for years, built a couple of systems in the past that were extreme. Not wanting to go that far, just looking to increase the clarity, and have access to the iPod for drives.

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Right now I have the stock radio (which I will keep, love the look) and it has steaming capability with my Yatour BT system. Have upgraded the front and back speakers with the JL C2's that I posted above and I have a separately powered sub woofer that plugs into the back of the radio and it sits behind the passenger seat. The stereo is okay, but nothing great. Just something to listen to, and not really loud.

I would say the Amp is a perfect fit:

BTW, where does the rubber plug go that is sitting in the bottom of the frunk in this picture: It was just sitting there....I know I've seen in somewhere before, but don't know where it goes. Spare part maybe?

It covers the headlight removal screw, under the carpet.

Thanks, had the headlight out recently to change the city light.

You've inspired me to get my stereo up to snuff. I have a bunch of old stuff lying around from back in the old days... time to see if any of it still works I suppose. Now where to put that Bazooka tube and Kicker C10's Lol.

I am interested in the way you installed your amp. The PO of my car got rid of the PCM2 and Hi-FI upgrade option 490 amp to install an aftermarket Kenwood double din GPS/bluetooth/ipod system with a similar amp than yours: JL XD600/6. It is well installed in the frunk, vertical behind the spare tire. I think the speakers are the OEM of the option 490. The problem I have is that there is a whining noise at low speed coming probably from the alternator (noise following the rpm). There is a fuse wired in the fuse box that I think they used to get 12V either to the double din or the amp. Where did you get the 12V alimentation for your install?

I'm a big JL audio fan I had a full setup in my old car, its great stuff and was still working like new years later. They also have a great warranty policy too!

Dino- Will run unswitched power directly from the battery and will use switched power from the head unit using the original wiring.

Dino, I have pretty much the same Amp set up as you. The problem with the whining is the rca cables are too close to either a 12 volt power or ground wire. I had this issues for a while and just had to spend time making sure that those cables are a few inches away from power wires. In the frunk it's not to difficult. My problem was under the dash where I had a hard time finding where the cables were close to a black 12 volt line. Maybe some kind of shield works too, don't know. Related (and I hope I'm not hi-jacking), I have the 6 channel JL with component speakers in dash/door. I have bridged the amp to run the left and right cross overs which takes up 4 channels and then bridged the amp for sub. So this leaves the rear speakers powered directly from the head unit. While the sound is great, it seams like it would be a little more well rounded sound with better power in the rear speakers. Since they come only from the head unit, they never have the power/volume of the other speakers. Anyone add a small amp for just one set of speakers? I bought all my stuff from CA Innovations and Rod is awesome, very helpful for DIY. Haven't discussed with him yet to see if there are options that are worth doing.

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I believe this is the most concise and accurate description of the 996's stock audio system I have seen to date. It is definitely a steamer.

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Try getting better grounds on your amp and/or radio and if that doesn't work put in a ground loop isolator... either of those 'should' clear up your alternator whine.

So phase I of the upgrade was completed yesterday. Installed the amp. The amp now powers the front dash speakers (previously upgraded) and the door subs, those will be replaced with the JL speakers in the upcoming weeks. I still have to build a sealed sub enclosure and run a wire inside the cabin to it. The old amp is still powering the rear two speakers. Here are some pictures: I have the M490 option for the six speakers and small amp located in the frunk: It has two connectors, basically the goes in from the head unit and the goes out to the speakers, plus the other required signals/power. There are only "front" and "rear" inputs into the amp, the sub outputs is derived from those inputs. So I made the choice to keep the "rear" input as-is and have the existing amp continue to power those speakers vs. abandoning them in place. The amp I used can just take one right/left signal and use it for all five channels. Here is the input to amp from the head unit and the +12 VDC switched power to turn it on: So I just cut the front speaker wires and connected them to a RCA input:

I tapped into the 12 VDC switched power to turn the new amp on also: So then I cut the wires at the amp output that run to the front speakers and the door speakers, leaving the rear speaker wires in place: I used 4 GA wire for power and ground with a 60 amp fuse. There is a ground location in the frunk that is super easy to connect to: I put the old amp back in place and for now am just using velcro to hold the amp in place. I plan to put two screws in on the inboard side of the amp, but don't know what's below it, so have to research that first. I just drilled a hole through the existing rubber grommet for power, will seal it once I get the sub wire in also. Talk about an INCREDIBLE difference in sound already! So much more power! Looking forward to getting the sub in and having a highly upgraded stereo that still has the stock head unit. Look at the post on page 1 if you want more details of equipment. BTW, when I started the car back up (had the battery disconnected for 4 hours or so) the gas gauge read dead empty with two low level lights on. I thought for sure I did something to the wiring, I thought I had 1/2 a tank or so. The sending unit wiring is under the battery....so I took it to the gas station and filled it up, took 11 gallons and the gauge read full. I'm not going to try and troubleshoot that one....but hopefully it was just an anomaly! More to come.

Project Subwoofer this weekend. Took quite a few hours, but I took the seats out and had to clean the carpet on the passenger side from some leak, still not sure where it came from or what it was. Anyways, took the seats out, took the old sub out that was behind the rear passenger seat, ran the sub wiring and installed the sub.....sounds AWESOME! Subtle but awesome. That's how it should be IMO. I made a sealed enclosure box to minimize size, made it so it would fit behind the rear seats. Not pretty, but it doesn't have to be. I ran a 10 ga speaker wire from the frunk to the rear of the car. To pass through the firewall, just unbolt the battery hold down bolts, unbolt the negative wiring from the battery, slide the battery to the passenger side of the car and you'll see a big grommet at the firewall. I removed it, drilled a hole and put the wire through it and sealed it was silicone. Here is the amp all finished up, just love how small it is. The box fits like a glove! At some angles in the direct sunlight the carpet looks like different colors at different angles is does not. I had bought a piece of carpet off ebay that was from a cab behind the seats for this piece. Here it is installed: And I had a chance to really clean the interior, treat the leather, it's super clean. I love the mods I have done to the interior. Next step is to replace the door subs with full range speakers, but that's another day. Awesome sounding right now!!!

About to go partway down this road on a 986. Head unit is updated, keeping stock amp for now - but want to replace dash and door speakers. If you were doing this again today would you pick the same speakers in those locations? I won't have a sub.

I think the fuse for the amp located in the firewall compartment next to the battery sits too low, water can accumulate in that area. To elevate I zip tied mine to the black bar that runs diagonally in the same compartment.

So I finished the stereo upgrade the other night. Wow, what a difference! Sounds incredible. What I did have to do different from what I said above, was to basically disconnect the back panel side speakers because I needed to have fading between the door and dash speakers. I did this by taking the input into the amp and moving it from the old amp to the new amp. You couldn't hear anything from the back speakers anyways with the new amp. Without doing that, the dash speakers were so BRIGHT and there was no balance. Anyways.....to put the Polk speakers in the door took minutes. Okay, the first door took hours because I did it the hard way (followed another post here, cut everything up, fiberglassed stuff back in, etc.). The second one I just had to dremel the enclosure out at the 3 o'clock and 6 o'clock position and the speaker would just sit in there. That's how I would do it. Here is all you do: Once I got those in, just had to tune it a little, which was really to lower the gain on the front and door speakers, keeping the sub level where it was when I set up the output voltage of the amp in the open circuit condition. It's got lots of bass, highs and mids, and it gets LOUD. I have to fade to the door speakers (rear channel) to about -2 or -3 to get a balance between them and the dash speakers so they are not so bright. Highly recommended, and I love that I have the factory deck still in place, I did install bluetooth, so I can stream whatever I want to it.

Nice work! I have a leftover JL sub and JL amp from my last car that I'd like to eventually get into my 996... Did you end up fixing the gas tank issue? My car's gauge is inaccurate as well. I think it requires filling up the tank completely and then disconnecting the battery. Do a search, lots of folks have had this issue.

Filling up the tank resolved the fuel gauge issue.

Looks good but two things: Plywood is not a good cabinet making material... MDF makes a much better sound... plywood tends to resonate. Fill that box with polyfil if you haven't already and this will help it some. The other thing is you should cut the carpet so that the speaker can seal against the box. The carpet is allowing air to escape and it changes the response of the sub... again just a little but you went to all this trouble you may as well make it as good as you can. On a side note... if you don't have the box fastened down please put that on your short list of things to do... you're a front end collision away from taking a 40 pound bat to the back of the head... I've seen it and seen the carnage from it. Otherwise great job... it's amazing how much good a little audio upgrade can do.

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That's another one on my list

I have the 490 Hi-Fi option and while I don't think it's bad, I wouldn't mind a little more base. What do you think would be the best bang for the buck for an incremental upgrade? Door speakers?

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The biggest bang for the buck would be to install an amp. Then probably replace the dash and rear speakers.....leave the door subs in. Or at least that's what I'm thinking. See if the amp I have comes in a six channel version....or potentially just put the two subs in series, they will become a 4 ohm total resistance total.

I kept my car looking completely stock, but sounding completely custom. If you get the right pieces, you don't need to do anything weird to your car, or install anything unsightly. You'll get the sound you're looking for. You can read about what I have in mine here: https://zerotoflatsix.com/2017/04/13...and-played-on/

Nice work on the dash, how did you fix it?

Well done, very nice work and glad you're happy with the results... R.