[krj65]

First forum post –greetings to all from Kansas. I picked up my 2010 335d last month and was disappointed to find out the standard stereo was no longer amplified and had rather poor sound quality. Following some research on this sight (http://www.e90post.com/forums/showthread.php?t=182752) I found out BMW offers an upgrade for the standard stereo, but it is not available in the on this side of the Atlantic. I did not want to order the BMW unit from a dealer in Europe, so I replicated the system with aftermarket equipment.

For the amp I used a Sony XM4S. It has high level inputs and a signal sensing turn-on feature so it was very straightforward to wire. This amp is also small, so it fits in the area under the trunk floor adjacent to the rear seats. This is important in the Diesel since the urea tank takes up all the other area under the trunk floor.

Wiring the amp is similar to the diagrams in the thread above- taking the high level inputs from the wires going into the subwoofer below seat and then running one channel of amplified output to the subwoofer and one to the door speaker on each side.

The hardest part of installing the amp was taking off all the trim to run the wires down the side of the car. Note for novices like myself - after prying the trim off, remove the brown retaining clips from the car and install them on the trim prior to reinstalling the trim. Also buy quality wire strippers and crimpers.

For the door speakers I used MB Quart RUA 213’s as shown on this post: (http://www.e90post.com/forums/showthread.php?t=290683 ). These were very tight on depth and I had to really fiddle with the driver’s side so the window would not hit it when going up and down. I also found it more straightforward to mount the crossovers on the door panel and not on the door as pictured in the above thread. I just fabricated some aluminum brackets and screwed them into the polystyrene at the bottom of the door panel.

I also ordered the BMW window trim pieces (http://www.realoem.com/bmw/showparts...13&hg=51&fg=10 ) so I would have a place to mount the tweeters. The MB Quart tweeters fit perfectly with a bit of Dremeling to the plastic surrounds on the speakers so the standard BMW tweeter mounting clips would work. Installing the window trim took a bit of perseverance, but as I said, I’m a novice at removing trim.

The result of installation was good. The performance of the stereo is now about as good as the Hi Fi system in my previous 335xi for an investment of about $300 in parts. I did not even need to remove the head unit.

Now to my problem -- since amplifying the front speakers was so easy, I decided to add another XM4s amp for the rear speakers. Unfortunately after doing this, it is clear that the input to the rear speakers has a high pass filter on it. Does anyone know if this filter is removable or is it integral to the head unit. Is there another good way to get a full input signal for the rear speaker amp?

[tgb1974]

I take it you do not have iDrive. I say that because I have read on here that a connector going into the iDrive are different for MY 2010. There are several posts by Technic regarding this. Technic will also likely be able to answer your precise question.

[Lee Rambler]

if you can live without fader (you'll still be able to adjust the front to rear balance with the amp gains), split the input from your front channel amp

[krj65]

Originally Posted by Lee Rambler

if you can live without fader (you'll still be able to adjust the front to rear balance with the amp gains), split the input from your front channel amp

I'm going to run the rear channel input on the "rear" amp from the front speaker input and hook up a sub to the rear channel output on the "rear" amp for now. I'd still like to be able to get a full range rear signal though. I should still be able to fade the rear deck speakers.

When I split the high level input between amplifiers will I have to turn up the gain? I already split it once between the front and rear inputs of the "front" amp.

[Technic]

The OEM HU/iDrive outputs the high pass signal to the rear speakers internally, not thru external filters.

So if you want a full range signal in the rear speakers you will need to split the front signals into your amps F/R inputs.

[VP Electricity]

Originally Posted by krj65

I'm going to run the rear channel input on the "rear" amp from the front speaker input and hook up a sub to the rear channel output on the "rear" amp for now. I'd still like to be able to get a full range rear signal though. I should still be able to fade the rear deck speakers.

When I split the high level input between amplifiers will I have to turn up the gain? I already split it once between the front and rear inputs of the "front" amp.

If you use an Autologic tool to change your HU coding to "HiFi", without changing your vehicle order, you will eliminate:

- your rear highpass xover
- your front subsonic xover
- your front and rear fixed EQ curve

But let's get right to the really important question:

How loud is your gong?

[kaigoss69]

Why is the gong volume an issue? In my mind this is only a problem if the amp gains are set too high, no?

[wurz154]

Originally Posted by krj65

For the door speakers I used MB Quart RUA 213’s as shown on this post: (http://www.e90post.com/forums/showthread.php?t=290683 ).

I am glad to see somebodyelse here tryed them...

Originally Posted by krj65

These were very tight on depth and I had to really fiddle with the driver’s side so the window would not hit it when going up and down.

Now we have more info to the forum and even if the e9*'s appear to be all the same ... they are not.. I did not have any depth nor mounting issue (e91 320d)

Originally Posted by krj65

I also found it more straightforward to mount the crossovers on the door panel and not on the door as pictured in the above thread.

My solution was more complicated or less convinient, but I thought it would be easier in the future when in need to pull the door panel; in my case there is only one cable (the one to the woofers) instead of two... that's because of the tweeter being with the door trim instead of the panel.
For my rear doors, however, I installed the crossovers to the door panel as you did. Very good info to the forum.

Originally Posted by krj65

Unfortunately after doing this, it is clear that the input to the rear speakers has a high pass filter on it.

I left the high pass to the rear speakers because the RUA210 will not handle much power expecially at low frequencies (that is true for most of the 4" out there); I wouldn't change that.
Cheers Max

[VP Electricity]

E90/E91 sedan/touring has same depth and E92 coupe is shallower.

I am not clear which body style OP has.

[Technic]

Originally Posted by VP Electricity

E90/E91 sedan/touring has same depth and E92 coupe is shallower.

I am not clear which body style OP has.

The 335d is Sedan-only, so the the fitting of those 213 should not have been that difficult based on the original installation.

[VP Electricity]

Not only that, you can't tell you HAVE a depth problem until your window hits the speaker

[Lee Rambler]

the RUA213's will fit the e92 with some modifications to the basket (sort of thankfully it's plastic and easy to Much easier than I had expected, with the exception of the extra time to grind down the "legs" of the basket. They work fine afterwords though, with improved midbass. I had assumed they would be harsher than they are, and started out with the tweeter level at -6db, but think I'm going to settle with it at -3db. Pretty pleased with them for the cost and considering they aren't broken in yet.

On to the rears now, hopefully I'm pleasantly surprised with how easily they install too....

[krj65]

Originally Posted by VP Electricity

If you use an Autologic tool to change your HU coding to "HiFi", without changing your vehicle order, you will eliminate:

- your rear highpass xover
- your front subsonic xover
- your front and rear fixed EQ curve

But let's get right to the really important question:

How loud is your gong?

Thanks to all for the feedback. My gong will get your attention. Its not unbearable set at -5 though.

I'm reasonably happy with the sound of the system now. The rear amp is powering inexpensive Kicker KS400 speakers in the rear deck and a Sony 10" enclosed sub mounted on the back of the back seat. The input for the sub is from the front speakers, but after I set all the gains, I can live with not being able to use the fader on the sub, as I can just lower the bass setting on the head unit if necessary. With the sub working in back, the high pass filter on the rear deck speakers is not a big deal either.

Interesting information on the programming though, I wonder if the dealer would do that?

[VP Electricity]

Dealer can't. Dealer SW does not support it.

I'm glad you like what you have.

It's better than stock, I'm certain.

Ever hear a really nice hi-fi home setup? Like two-channel, audiophile stereo goodness?

[krj65]

Originally Posted by VP Electricity

Dealer can't. Dealer SW does not support it.

I'm glad you like what you have.

It's better than stock, I'm certain.

Ever hear a really nice hi-fi home setup? Like two-channel, audiophile stereo goodness?

I have not heard a really nice set up. If I did, I'd realize how poor all my stuff sounded and it would be really expensive to replace it all.

One more question regarding phase that I did not find answered with a quick search: In theory, should I run the fully enclosed sub in the trunk opposite phase with the subs under the seats, since I believe the stock subs are firing downward and vented to the cabin?