2011 Atacama Yellow Build

[Lurcher]

Crap, I had to go back and re-read that - and yea WTF BMW? I thought the subs would be "mono". not the 6.5....

OK - I'll get into the software in the morning and see how mine is set-up. 102 F outside and 91 in the garage right now....

[fmorelli]

Originally Posted by Lurcher

Crap, I had to go back and re-read that - and yea WTF BMW? I thought the subs would be "mono". not the 6.5....
OK - I'll get into the software in the morning and see how mine is set-up. 102 F outside and 91 in the garage right now....

THat would be helpful. So bimmertech's existing harness for the E89 Z4 is wrong. It killed the bridged mid-bass footwell woofers. They are fixing that and getting it out to the two (?) e89 Z4 owners of that amp. Insane. Where is the rest of the world, lol.

Okay I've been thinking about this and would like your thought. I'm thinking about making a harness to route the center channel wiring down to the bridged footwell woofer. The bridged woofer as I read the ETK is in the passenger right side. So anyway, I'd run the center channel down there. Then, I'd hook the right-side footwell woofer to the center channel wire instead of the bridge wire. Then obviously the center channel speaker is no longer connected. This would allow the car to have 8 channels, no bridging BS across channels. Mid-ranges bridges seems like a really bad idea. And for that matter, a center channel in a stereo seems like the answer to a question no one ever asked. Given the DSP setup, the car can be tuned appropriately for this setup.

Thoughts? Am I missing something or getting something wrong?

Filippo

[Lurcher]

OK - here we go.

My amp (for the record: Audioson AP8.9 bit - same as yours, different software) got installed "correctly", with the 6.5" channels separate and the woofers separate (no change) as well.

PM me with your email and I'll send you my sound file. The extension is different in the sound files of my 2 amps (A-Fischer PP82DSP in the x3), but I bet they will either work or you may have to change the extension. There is no way to print the config (sucks). Worse case I can take some pics and post here.

Finally got a chance to use that fancy new microphone with a RTA on my phone, just to prove how much the tweeters suck. The roll-off above 10k is embarrassing - I guess BMW assuming us older guys are loosing it anyway. My config is a little heavy on the bottom end to allow for top-down driving. Used Michael Jackson, Basia, Boz Scaggs, Donald Fagen, Miles Davis to tune.

Time to get sweaty and install the new speakers (Jenherts...)

So, I'd be doing exactly what you are suggesting - use the center channel wiring, run and extension down to the right 6.5" and call it a day. In the software you can rename everything anyway.

My next question is how are BimmerNav "rewiring" the new harness? Is the old one the right one now to use for this change?

And just to close out - center channel is good for all of the DVDs we play while driving....great marketing...

[fmorelli]

Originally Posted by Lurcher

My amp (for the record: Audioson AP8.9 bit - same as yours, different software) got installed "correctly", with the 6.5" channels separate and the woofers separate (no change) as well.

So you have the amp installed with stock speakers, but are about to upgrade all the speakers using Jenherts? Can you post what you are installing?

I don't think this is the same amp as mine. The Audiotech Fischer, which bimmertech uses, has the following specs:
8-channels
at 4 Ohms 8 x 55 Watts / 110 Watts
at 2 Ohms 8 x 70 Watts / 140 Watts
THD < 0,02 %
4 x Highlevel, 1 x Aux, 1 x Optical
DSP Processing Power: 172 MHz, DSP Resolution 56 Bit

Originally Posted by Lurcher

PM me with your email and I'll send you my sound file. The extension is different in the sound files of my 2 amps (A-Fischer PP82DSP in the x3), but I bet they will either work or you may have to change the extension. There is no way to print the config (sucks). Worse case I can take some pics and post here.

Done. What software are you using?

Originally Posted by Lurcher

Time to get sweaty and install the new speakers (Jenherts...)

Originally Posted by Lurcher

So, I'd be doing exactly what you are suggesting - use the center channel wiring, run and extension down to the right 6.5" and call it a day. In the software you can rename everything anyway.

I will try and work on that now (I just took a break from the garage to come in and read your note). I'll shoot photos if I figure out the harness/routing/connector.

Originally Posted by Lurcher

My next question is how are BimmerNav "rewiring" the new harness? Is the old one the right one now to use for this change?

So we didn't get into what's wired wrong. My guess is that it is an F30 type harness or something, that doesn't plumb the footwell woofers (since they don't have them). The cursing part of the E89 Z4 is that, while it uses parts bin stuff from the E9x, E46, or is forward used in the F30 ... there is plenty of stuff that is just ever-so-slightly different.

Originally Posted by Lurcher

And just to close out - center channel is good for all of the DVDs we play while driving....great marketing...

Really the question is ... why on earth, BMW, would you plumb a near useless center channel, and bridge a mid-range speaker which muddies stereo separation? Spend less money, kill the center channel, wire the footwells correctly, and be done. What a mystery ...

Thanks for your posting ... very helpful!

Filippo

[fmorelli]

Buttoning up the front of my car, I wanted to "fix" the headlight leveling setup I had on the car. The setup on the Z4 is pretty hokey. Unlike the E9x which has a boss on the arm to mount the headlight leveling arm, the E89 uses a metal strap (which of course does not fit the M3 arms, and the boss on the M3 is on the driver side versus the passenger side leveling unit on the Z4).

My previous bracket had broken, in part because the bracket has slits which leave very little metal. As a result when trying to wrap the bracket around the bigger M3 arms, and using some other means to clamp it in place (wire ties, coolant clamps, etc) it is easy for the metal to flex and break.

My new setup uses a T304 stainless steel wire tie, which is thin enough to feed through all the bracket slits. This helps distribute the stress (hopefully this one won't break).

A couple things on the install.

1. I flattened the bracket somewhat, where it goes across the top of the control arm. Couple needle nose pliers help.
2. Toward the end of the bracket, on one side, is a big square indent (probably for the clasp. I pushed it through to the other side which helped in running the wire tie through. This is obvious once trying to put this together.
3. I went through two wire ties, having a hard time cinching it the first time. The second time, I used locking pliers to push the bracket tight against the control arm (top to bottom). I then used pliers to help pull on the stainless wire tie while I used a screwdriver pushing against the wire tie clasp, to help cinch everything tight. Unlike a plastic tie, I discovered that one wants to pull the stainless tie parallel (straight) from the clasp. If one pulls at an angle it is easy to bend the inside clasp mechanism, and the tie will not hold securely.
4. As insurance, I put a black plastic wire tie on either side of the arm (stretching it nice and snug) to make sure nothing moves around.

Filippo

Here's how I routed the wire tie. Note that the top is flattened, and the little tab at the top is now pushed out versus in, so the wire tie goes through easily.


Mounted. (yes the arm looks oddly bent - that's how these come from BMW)


Here's the part number, for those looking: 37146783206

[Lurcher]

Amp is all but the "same". Bimmertech changes something on the board to call it "special". All the plugs and harnesses are the same - I'm using their wiring harness on my A-F amp in the X3 (per Nelson - even though A-F manual says not to use factory harness for power. Hmmm....)

All of the BMWs with the 676 amp/speaker package us the same plug (I'd bet even the HK system uses the same plug). Most people probably see the value in the center (having one in a a home theater makes a difference) and with the ability to play DVD's - it's pretty much needed for "surround sound" (again - marketing the Logic 7 system)

I'm using the audioson software - each manufacturer puts their own spin on it - I should have pulled up the A-F software to see if it would connect to my Audioson - something for another day.

http://www.jehnert.de/shop/doorboard...woofer-system/

Just the mids-tweets - bought them used without woofers for a steal ...

[fmorelli]

Alright, so today I worked on fixing the ridiculous bridged mid-bass woofers in the footwell. This is a surprisingly bad violation of basic principles for stereo sound. Effectively passing the left side encoded sound to the right speaker muddles the stereo separation in the mid-range. The following photos should help for anyone looking to do this. Simply since I am programming my own DSP, I am routing the dedicated center channel to the right footwell mid-bass woofer so it is now on its own dedicated channel (as it should be).

I pulled the center channel, ran a steel snake down from the small slot on the right side of the center channel frame until the snake came out of the passenger side footwell. I had a spare connector (thanks to Bavsound) for the new harness.

Filippo

The undertray panel is already removed below (3 torx bits), and the footwell woofer panel is also removed. Here I show the dash side panel removed. A plastic removal tool will help - it's just 3 clips and pulls out. I pulled the door rubber molding as well. Note the snake has already been pushed through and I've taped the extension wire to it so the wire can be pulled back up to the center channel.


Here you can see the snake heading down to the passenger side. The snake is what one would buy at the hardware store to snake a clog in plumbing.


Here is the snake coming through passenger footwell. Photo is taken from the floor upwards.


I ran the wire up behind the glove box.


Ok ... about 3 inches above the speaker hole is a 1" body hole and then into the speaker hole. This photo is taken from the floor upward.


Here's the speaker connection at the center channel.


Bavsound has connectors. I had this spare harness which I clipped off the male connector and used to make the center channel harness extension.

[Bstears]

Hi everyone! I'm really glad I found a living post on a z4 forum! I've learned a lot reading through this thread. I'm the other guy who bought the bimmer tech amp for my 2011 z4. I installed it about 2 weeks ago, and quickly realized the kick panel mid bass speakers were not working. I contacted bimmer tech, and they responded in a way that made me realize they weren't aware of these speakers. Eventually they called and we realized a new wiring harness was necessary.
Anyway, my plan is as follows:
I ordered the stage one speaker upgrade from bavsound. I also ordered their ghost subwoofer upgrade. They come in the mail tomorrow. I already started taking the back apart and have some dynamat ready to add. I'm hoping that between the BT amp, after the new wiring harness, and the stage one upgrade with the ghost woofers, the s676 sound system will be decent enough. It will end up costing about 2k for all the equipment. Sometimes i wonder if I could get a better system for the money at an audio shop. But I don't like the idea of them cutting into wires.

[Bstears]

Also, I was wondering about disconnecting the center channel and reassigning it for the midbass woofer. My understanding is that the head unit on the 676 sound system is always processing music in surround sound. We can't turn it off. So how much of the left and right channel is being sent to the center speaker? Is it redundant sound? Or will is it filtering sound out of the left and right channels for the center channel? I'm wondering if you will be missing out on sound by removing it. I believe the bavsound stage one upgrade includes a center channel replacement speaker which could mean it's important enough to upgrade.

[Lurcher]

That processing of the center is handled by the amp. You can look at the wiring harness into the amp and see there are only 4 discrete channels being provided.

[fmorelli]

Originally Posted by Bstears

Also, I was wondering about disconnecting the center channel and reassigning it for the midbass woofer. My understanding is that the head unit on the 676 sound system is always processing music in surround sound. We can't turn it off. So how much of the left and right channel is being sent to the center speaker? Is it redundant sound? Or will is it filtering sound out of the left and right channels for the center channel? I'm wondering if you will be missing out on sound by removing it. I believe the bavsound stage one upgrade includes a center channel replacement speaker which could mean it's important enough to upgrade.

I had a sneaky suspicion the "other" Z4 bimmertech amp guy would surface ... Lurcher ostensibly has the same amp, and also a unique set of speakers, so helpful to have him in the mix as well.

General reading I've done, any number of folks have had positive results getting rid of their center channels (for whatever reason). In our case we have the need to do that as sending mid-range left side stereo signals to the right side footwell woofer is guaranteed to muddle stereo separation. To me, reprovisioning the center channel to create a proper right mid-bass woofer channel is a no brainer.

On the head unit, how is it that you know this center channel wizardry? In looking at the TIS, it seems to say that 4 channels come out of the head unit to the DSP. Here's the TIS description.

Here is the wiring out to the speakers, which was linked here before but the image is dead in the prior post.


(link to 676 HIFI speaker output schematic)

Filippo

[Bstears]

Sorry, I shouldn't have said head unit. You guys are much more knowledgeable about this stuff. Is the center channel simply outputting a combination of the left and right front speakers? Or is it processing the signal and pulling out voice?

[fmorelli]

Once you have the new amp in play, whatever BMW does with the center channel becomes moot. :-)

Maceij @ bimmertech agreed with me - that the center channel should be repurposed to solve the bridging issue on the Z4. Hopefully the above photos help. The only trick is that you need to aquire a connector. One way to do it is to clip it off your stock center channel speaker (one can always resolder that on). I'm just adverse to cutting the factory wiring harness itself.

BTW I don't know that I know that much more ... I'm pushing my way through this bit by bit, and thankfully others here are providing some information and help. A high tide raises all boats.

Filippo

[Lurcher]

Originally Posted by Bstears

Sorry, I shouldn't have said head unit. You guys are much more knowledgeable about this stuff. Is the center channel simply outputting a combination of the left and right front speakers? Or is it processing the signal and pulling out voice?

Yea, summed mono center channel. But, when playing DVD's in surround sound - the center does have all of the dialogue.

AMP is doing all of the work here...

[fmorelli]

Slight diversion. I purchased an Asus Zenbook a few weeks back, upgraded it to a 512SSD, and started working on getting a garage laptop set up so I can tune the stereo system DSP, and also so I can do programming and diagnostics on these modern BMW's. I need to sort out the software installs, but the hardware arrived from China today from a reputable seller and just over $200 shipped. Hard to beat,and this will pretty well talk to every BMW in a 20+ year span I've got sitting around here. In case anyone is interested, here's the seller's listing on Aliexpress. There are a few coupons which can drop the price. This is about $100 less than on eBay I believe.

I wish I had this when I was recently trying to diagnose the top issues on the Z4 ...

Filippo

[Bstears]

So just for the sake of discussion, although not many z4 owners have been through this, or at least haven't posted about it, let's assume that used z4's are coming to a price point that people will be buying them who may want to do what we are doing by swapping parts and upgrading them. But, for the masses, they may not want to cut into wires. How much impact on quality of sound would be had by the average person swapping out the BT amp, using the revised wiring harness that sends one signal to the kick panel woofers, and being done with it? Did bmw send one signal to those speakers because they are so far into the footwell that they don't have much impact on sound, more just bass? Bavsound's advice was to go into the amp's software and do a low pass filter at 250hz for those midbass woofers. I wonder if doing that would eliminate the problem of muddying up the sound because they would be acting more like subwoofers right? Keep in mind, I know just enough to sound stupid.

[fmorelli]

Those are good questions. First of all I just know it is a basic violation to send the left side signal to a right-side speaker. Only A/B testing of two configurations would tell us how much of a difference it makes, and I honestly have no guess. Bavsound's suggestion is not a bad one (low frequencies are non-directional), but really kills that speaker pair's contribution ... not to mention it is a mid-bass woofer, not a subwoofer. And if one had a factory speaker in the footwell, I don't even know if its performance specs would lend to the Bavsound suggestion (though they would know).

Sorry I don't have any clear answers. With the car apart for speaker installation, this is not a lot of work - that is, to run the wire as I did.

Filippo

[Lurcher]

I'd say that most people would put the amp in and call it a day - that is - if a specific sound file is installed/available for the z4.

If you are physically replacing the amp - you are already investing some time just to get to it - no "easy access panel" like in my x3. I'd suspect at this point someone would be replacing the speakers as well (I'v had the stock speakers with my amp for 3 yrs now, but only drove 8k miles mostly with the top down), so they would be doing the speakers as well. If you do the speakers, **and** read about this issue, then why not run the wire and correct things.

Or be lazy like I was and have a shop do all of this for you...

Putting this amp in with zero configuration drove me nuts, as I tried it :-). It actually sounds worse than stock (as expected). Obviously Bavsound does not have a file for our cars, and they have only sold 2 of these amps, so they are probably not too concerned about any of this. I'd dare say 75% of the people getting this amp will never tune it farther than the stock configuration, regardless.

Lots of rambling, but on the e38 board, we saw a lot of new blood coming in when the price point got below ~$10k, and the modding was much more active. Will be interesting to see what happens here....

[fmorelli]

Originally Posted by Lurcher

I'd say that most people would put the amp in and call it a day - that is - if a specific sound file is installed/available for the z4.

To my knowledge there isn't a specific Z4 file, at least from bimmertech ... they sent me an F30 file, which we know doesn't have 6.5" footwells and the woofers are under seat, et cetera. Hopefully when I'm done, I'll be able to post my file with my specific configuration. And I may have someone with significant DSP experience, locally, do the tune. That's TBD though, as I'm not there yet.

Originally Posted by Lurcher

Or be lazy like I was and have a shop do all of this for you...

I actually considered this, but given the alcantara interior in my car I was concerned about someone screwing up panels ... and I know how these cars are assembled so I was more comfortable doing the work myself. BTW for those doing their own speaker installs, the Bavsound E89 Z4 video for Stage 1 coupled with the Z4-forum post on the subs ... I think the DIY is doable. But yeah I quality sound shop would do a great job I'm sure.

Originally Posted by Lurcher

Putting this amp in with zero configuration drove me nuts, as I tried it :-). It actually sounds worse than stock (as expected). Obviously Bavsound does not have a file for our cars, and they have only sold 2 of these amps, so they are probably not too concerned about any of this. I'd dare say 75% of the people getting this amp will never tune it farther than the stock configuration, regardless.

Drove you nuts, eh? So just to be clear, Bavsound won't sell this for the Z4. They actually sent me to bimmertech directly. Who sold two of these (at least that I know) and are rectifying a cabling issue.

Originally Posted by Lurcher

Lots of rambling, but on the e38 board, we saw a lot of new blood coming in when the price point got below ~$10k, and the modding was much more active. Will be interesting to see what happens here....

It is ironic (about these E89 Z4's) that they are no longer in production and we are still discovering these nuances in the cars. I'm kind of amazed, actually ...

Filippo

[Bstears]

So I disassembled the the area around the rear subwoofers, following that the post, which was so helpful. I didn't completely remove the large carpeted panel that covers the rear subwoofers as it has extensions under the center console and it seemed like I would break something to pull it completely out. But by unboltong it and releasing the tabs, it has plenty of movement in it. I put some sound deadening on the metal panel behind the subwoofer area just for good measure. After switching the factory woofers out of the housings and putting the new bavsound ghost woofers into the housings with a new seal, I installed the housings back into the car. I turned the system on before putting all the panels back together and quickly realized two things: one is that the bavsound ghost woofers definitely sound better, but still distort pretty easily. Maybe the new amp will help with this. Right now I'm using the stock amp. The second observation is that the bavsound woofers move more air because I got the annoying whistling sound when they would it hard. At first I thought the seal around the speakers must be leaking, but when I removed the housing from the car, the whistling stopped. I then considered a leak from the housings to the car where there is a space used for air flow. A new seal there didn't stop it either. I went to the trunk area where it sounded the loudest and put my finger over an empty bolt hole and the whistling stopped. I closed it with some sound deadening. Today I will install the rest of the stage one speaker upgrade and put the car back together!

[fmorelli]

That's good to know! I'll make sure to run my setup with everything apart. I will tell you, I did the Bavsound speakers first and then concluded that the amp didn't sound so great ... and then ordered the amp. Kind of how I dug myself into this hole.

I've not seen the Bavsound Ghost speakers (nor know their specs). The Rainbow IL-S8F (which is what was recommended to me by a German shop that sold several woofers which fit) are not particularly heavy nor have particularly large magnets. They are 90 db/w, 35hz-5k hz, 150W max @ 4ohms. Curious to see how they work. I hope to get to the woofers this weekend, once I get back from NYC.

Filippo

[Bstears]

I took pictures but they are too large to upload. I'll see if I can figure it out tonight. In the end, I may look into having a custom subwoofer enclosure installed in the depression in the trunk in between the existing woofers. I'm not looking for car rattling bass, just want it to be able to hit without distortion if I turn it up, especially with the top down. I have burmester in the C AMG and HK in the GL. I think I'm going to have to be ok with just ok sound out of the z4.