How to add a subwoofer?

[Z4 Coupe]

I’ve got the 10 speaker HiFi but not the Carver version and I’m looking to hook up an aftermarket amp to power a subwoofer. Now from searching the forum and Google it looks like I need one of these http://www.newministuff.com/new/shop.ph ... how&id=632 an Amp wiring kit and a spare afternoon.

Is the Mini Boost Rear RCA the one to go for? Will this give the low bass I want or is there a better place to get the signal from? The reason I’m thinking of this adapter is I’d prefer to not cut or splice if at all possible and I’ve used one in a VW in the past with great results.

[bcworkz]

I'm not convinced these will give you easy plug and play functionality in a Zed. If they plug in to the back of the head unit, running well hidden cable to the boot is not easy. You want to tie into the amp some how since it's in the boot already.

First thing to do is identify the sub amp you want. Many of them have a speaker level input which makes tying into the present amp really simple. If your chosen amp only has traditional line level inputs, then you will need some sort of adapter similar to what you have chosen, though I'm unsure if you will find a plug and play variant that works with the amp connector.

[Z4 Coupe]

Thanks for the reply. I thought that only the very top Carver HiFi had the amp in the boot? I can't see one where next to the battery or is it somewhere else on just the normal 10 speaker HiFi?

I've not got an amp yet and I'll probably buy one with low and high inputs to be on the safe side but I also have a pretty decent LOC leftover from an old car.

I will look myself but can anyone point me in the direction of where the amp is and what cables I need to tap into?

[bcworkz]

There's 3 levels of OEM audio. Some folks with the base 6 speaker get confused with the count as the door has grilles but no speaker behind them. The base system has no amp. The 2 10 speaker upgrades have amps, next to the battery pre-facelift, then on the boot forward bulkhead under the carpet on facelifts. Determining the difference between 10 speaker systems is not that easy. Most reliable is to get a build sheet for your vehicle and see if there is any mention of "DSP" for any of the audio options. If so, it is a top level system.

I've outlined what I believe is another reliable method here: http://www.z4-forum.com/forum/viewtopic ... 1&p=576909

[Adamski]

If you've got 10 speaker hifi - I'm not sure you'll be able to find extra bass without spending a hefty wedge. The BMW system is difficult to re configure.

Easier with the 6 speaker basic system


Sent from my iPhone using Tapatalk

[Z4 Coupe]

I've definitely got the non-DSP 10 speaker system as I've got the subwoofers behind my seat but no DSP option on the sat nav screen. I also double checked with the secret menu and DSP = 0. I must have been looking at pre-face lift pictures with the amp next to the battery as mine is a post-face lift I must have the amp behind the carpet.

So is it not as simple as tapping into the sub wires and running them to a LOC or high level input on an amp? What else would I need?

And I thought this would be easy as the battery is already in the boot

[bcworkz]

With the amp in the boot, most of what you need is right there, if a bit awkward to access. You just need the sub and amp, and a line out adapter if the amp does not have one built in. Then yes, hook into the OEM amp's speaker outputs. You also have the head unit output to the amp, not sure if they are line level or what. The one thing missing is switched power, oddly enough. The amp gets a switched signal from the head unit that is apparently digital and useless to retrofits, IIRC. Be worth confirming that, as switched power back there is rare. If you have the mobile bluetooth, the TCU box also on the bulkhead has switched power though.

In case you didn't notice, there's a couple other subwoofer threads active here right now, worth checking out if you aren't following already.

[Z4 Coupe]

A bit more research is needed! Mainly on 10 speaker non-Carver HiFi pinouts I've the OEM Bluetooth and a multi meter so switched power shouldn't be a problem. Does anyone know if the pinouts for the non-Carver are the same a s this? http://www.billswebspace.com/A18%20Amplifier.htm

I've not seen the active subwoofer threads and I've done a lot of searching! Are they on the audio section?

[bcworkz]

That looks about right, a reliable resource, if you want to confirm, is http://www.bmw-planet.com/diagrams/rele ... /index.htm
Look under components->A18. There can sometimes be minor differences between model years and installed options, this resource documents it well. (The number of different mobile phone implementations is daunting!)

Sorry, I didn't notice which forum I was in, I usually just scan the New Posts listing. I'm pretty sure it was not the audio section, perhaps E85/6 general discussion? There were two other subwoofer threads I read yesterday, and I check this forum nearly every day.