dadrocker

I think I've mentioned elsewhere that, last weekend, @bruce_miranda graciously helped me through replacing the OEM subwoofer with a Kicker Key Amp, a Basser Box, and a 10" JL Audio subwoofer.

Before this, the last time I worked on a car stereo was probably 25 years ago or so. So I was rusty, and in any event a complete rookie in a modern system like the one in our cars. I put together the attached document to help illustrate and outline the steps involved in this project. I am not an authority, and my knowledge on the process is shallow. If you're fully comfortable working on your system right now, this guide will do you no good. But if you're nervously curious, check it out. It's quite doable, and the improvement is well worth the effort.

Feel free to PM me with any questions, typos, clarifications needed, etc.

dadrocker

Someone was selling surplus black rings for the back of a TT (I think). I thought it might look cool to slap these on the subwoofer's grill. It's almost a good fit, but not quite. I think the adhesive will hold them in place, because a lot of the rings are in contact with the grill. But I'll have to be careful not to snag something on the protruding ends at some point.

Black rings for rear of TT on grill for JL Audio 10" subwoofer.

Black rings for rear of TT on grill for JL Audio 10" subwoofer.

Not a great fit - the rings are a bit longer than the flattest part of the grill.

Zed 2.0

This is a great writeup.

dadrocker

Thank you. I hope it helps people improve their systems.

Mortys66

I think this is a great write-up and it can be easily followed from start to finish. I would feel very comfortable following this guide and choosing the recommended items or upgrades.

I would like to add my 2 cents for the decision needed in step I. A., on 'keeping the OEM B&O subwoofer' or 'loosing the OEM B&O subwoofer'. At my initial onset of wanting more from the B&O, I was going to be keeping both the stock B&O subwoofer & stock subwoofer enclosure (with a new aftermarket 6 1/2" driver only) along with adding a 10" JL Audio subwoofer powered by the Kicker KEY 500.1 amp. My main reason I was wanting more from my B&O low end was a muddy and relatively undefined low end sound that did not fill the interior void with a good sound and low end feel. With Bruce Miranda's guidance, I also was able to add the subwoofer and amp to the OEM B&O subwoofer using the wiring jumper Bruce made to keep both the B&O and the aftermarket systems powered on. However, when I had both subwoofers powered on the low end output was still muddy and lifeless for me, although I could feel the punch and hear better sound overall, I still was not happy with the muddiness the bass delivered. My chosen style of music that I like to listen to is hard rock, alternative and classical rock. I am a person who likes a clean sounding drummers kick drum (or 2, depending on the musical artist) or a well defined bass guitar riff or track. This sound is something that I want to hear cleanly and well defined, but also I want to feel the low end beat inside the car's cabin. I'm not a fan of just turning up the volume for loudness sake to rattle everything around me and the vehicle, however I am a fan of loud clean, well defined music and vocals. I don't want my low end range to be heard thumping down the street before I arrive, so this is the reason I overload on the soundproofing or sound deadening in all the areas of the car that hold the speakers. I feel this OEM B&O subwoofer delete makes for a much cleaner and easier installation of the aftermarket amp and subwoofer. I also feel more satisfied with the addition of only the aftermarket products because they produce a much cleaner sound and allow the user a large range of adjustability, that just is not there in the stock OEM Audi B&O sound system. This upgrade alone is worth more than the price of the components and my time, for me, this is one of the 'Must Do Projects' if you own the Audi B9 platform.

bruce_miranda

I am so glad you took the time to write this up. Far too often you have people come asking for help, get it and then give nothing back. I find that rather selfish. Even if they came back just to say if their issue was fixed or not with the help they got would be great. Otherwise what's the point of these forums. So Thank You.

There are benefits to keeping the OEM subwoofer i.e. B&O amp loading, Bass backup (in case your kit fails) and a quick way to return to stock - especially if you are using something like my cable.
But ideally you should remove the OEM subwoofer unless you have a way to control it's coexistence with the new subwoofer. Two different sized and capable drivers shouldn't be operating in the same frequency range.
To counter this, I installed a 4 channel amplifier and used 2 channels bridged to run each subwoofer. This way, I can alter both the crossover points and the gains of both subwoofers, independently. Oh, and I upgraded the OEM subwoofer to an aftermarket driver in the OEM enclosure. If I do things again, I wouldn't bother with the OEM stuff and go directly with a mono subwoofer amplifier driving a proper subwoofer.

S-works Tarmac

I want to thank you for your wonderfully detailed installation guide!! I took my sweet time and my Sub is all installed now. Thanks to Bruce as well for sending me this link. Aside from the amp being a little hot (is this normal?) everything is working great! Thanks again DadRocker.
Mike

m444

If you can place place your finger on the amplifier heat sink hot spot & hold it there for 10 seconds without burning your finger, it is fine, since the case is less than 60C.

From the Key500.1 amplifier manual:

"Choose a location that allows at least 4” (10cm) of open ventilation for the amplifier. If possible, mount the amplifier in the climate-controlled passenger compartment."

dadrocker

i’m so glad to hear that, Mike. Thank you for taking the time to add to the thread, with your excellent photographs. That is a satisfying project, isn’t it? With mine in the spot of the old OEM subwoofer, it is getting no ventilation to speak of, contrary to advice in the manual. That may come back to bite me someday. It also makes it a pain to check how hot it is, being buried underneath the spare tire. So, I can’t really say how hot mine is, but I will check the next time it’s been running and I feel like taking things apart a bit. Probably sooner rather than later, as I feel like tweaking some of the settings a bit. This is all another way of saying that if people can figure out how to mount it in the driver side cubby, which many have, that is probably a preferred location.

And, also, after living with it for about a month, I would say that I prefer using the remote power line in from the 12 V outlet, which is how I started, to not using that and getting the thump when I turn off the car. That’s a better way, and I should update my write-up accordingly.

S-works Tarmac

Yeah, I used the 12v outlet. The bass really does fill in the cabin.

Thanks again