kyee

I do have the B&O stereo system, but no stock system will ever have enough bass, at least for my tastes. I wasn't looking for a ghetto-blaster type system, just enough low end to round out the rest of the system. I don't listen to my music at eardrum shattering levels, and I definitely don't need to rattle the windows of the cars next to me.

I found an installer in my area that I was confident could do a very clean and reliable job on my car. In my 2 previous cars (E500 and 335i sedan), I went the route of a sub box/amp in the trunk, since those were leased cars and I didn't want to do any mods that couldn't be easily un-done. Since the S4 was purchased, I decided I could do this how I wanted, which was to build/fabricate an enclosure and retain as much trunk space as possible.

There aren't many options in the S4 trunk for a subwoofer install, we decided to put it in the rear left compartment, which meant we had to relocate the 2 devices which were there. The amp/receiver modules were moved up higher and deeper, and the cables rerouted. This gave us enough space to fabricate a fiberglass enclosure for the Hertz sub. The Audison amp was mounted up next to the stock sub, which was disconnected and left alone. I may remove it if I ever do Phase2 of the project, which would be to replace the front stock speakers.

Lastly, the sub gain control **** was located up front, so I can easily turn up/down the amp gain. Very convenient location, and looks like it came stock with the car.

Sound is excellent, exactly what I was looking for. I probably only use not even a 1/3 of what the sub/amp is capable of, but it gives me plenty of headroom should I want to really turn it up when the sunroof is open and I'm flying down the freeway. Best part is that I lost no trunkspace in the process.















One change that I'm thinking of doing is replacing the black vinyl trim around the subwoofer, with carbon fiber to match the theme in the rest of the car. Still debating that one...

tihsyloh

Looks great. Thinking if doing exactly the same thing. My guy said to do it on the other side as there was more room and no need to relocate anything. What did it end up costing you?

supraman66

looks as close to factory as you can get. Does the sub have a grill in case you have some loose items in the trunk? don't want a 3 iron punching a hole in it!

kyee

The reason we chose the left side, is that it's unlikely I'll ever need to access the devices on that side. On the right side is where all the fuses are, so it'll just be more of a hassle to get to those if needed. We figured the likelihood of needing to change a fuse was higher than accessing the amp/receiver hardware on the left hand side. I can still get to those if needed, it'll just take a little disassembly to get there.

PM me for pricing info.

supraman66

it is odd that the trunk springs on not on the same hook points which would be a small difference in tension. Just and observation.

Still sweet!

NWS4Guy

Brilliant! I have a 3-4 year old Alpine R-Type 12" sub in a very small enclosure which I had in my Lexus IS300 and never moved to my G35, I still have the MTM monoblock amp for it as well, I might look into something like this, but I have changed my preferences on lots of bass in these last years, and stock sounds good to me.

What do you do about a cover for the speaker? I know you don't want anything you put in the trunk to slide into the speaker and damage it.

kyee

I debated that one like you wouldn't believe. The grill that comes with this sub is ugly as hell. It's like a 3 prong claw that protrudes out another 2-3" from the sub face, and still has wide gaps that a stick, or 3 iron could punch thru. I almost changed the sub and went with a JL Audio W6 just because it has a better grill option. I like the musicality of the Hertz over the JL Audio, so decided to stick with it. I do carry equipment in my trunk on occasion ( I play in a band on the weekends), so I'm still trying to figure out how best to protect that speaker. In the end, I may have to just put the ugly grill on anyway.

ShadowJet

Wow, awesome install! Cleeeean. I'll keep on the lookout for a bumpin' S4, haha.

I think the black trim is fine. Although, carbon fiber would look nice and match, the weave may not be the same and it may get scratched up pretty bad being in the trunk.

primetime

Looks awesome.... will most likely do something once my car arrives.

I have a very nice setup in my 2000S4.... had the sub box custom made/mounted along with the amp and then a amp tray....

angina

well, it is your trunk, so I think protecting the sub would be more important than looks.. Still, its a great clean install.

So the stock amp is still in use to power the rest of the speakers, and you have an aftermarket amp to power just the new sub? Is the stock sub the one located in the rear deck right next to the audison amp in the pics?