# E39 w/ DSP front speaker upgrade



## ZeroDfx (Sep 2, 2005)

I cannot find the answers to these questions in the archives; can someone help?

1997 540i w/ DSP

I want to upgrade the front 5.25" door speakers with woofer/mid-range or 2-ways and the matching tweeters. In order for the replacement speakers to work properly with the existing DSP amp/system, what impedance do I need to select: 4 ohm? 2 ohm? 8 ohm? Or can they be mixed and what are the consequences? I'd rather not change the amp yet.

What is the maximum depth I can fit into the door; it seems like around 2 1/4" from what I can tell reading other posts. Is that correct or is it larger?

Thanks much for your assistance.
Nick


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## philip|bsw (Aug 4, 2008)

I am not sure on the exact dimensions of the factory speakers, but if you are still deciding on which speakers you are going to use you may be interested in our Stage 1 Speaker Upgrade for your e39. That fact that ours are plug and play can save you a huge headache because replacing your OEM speakers with "off the shelf" after-market speakers can't easily be accomplished in your car or many modern BMW's. The reason for this is that your factory amplifier has a separate channel for each individual speaker, and each of those channels will only play the certain frequencies that speaker was meant to play. On top of this the resistance and efficiency would not match your factory amplifier so the mid-bass sound would be very dim with most aftermarket speakers

Here's a link ----> Stage 1 Audio Upgrade for e39 5 Series

Feel free to pm or email me if you have any questions. :thumbup:


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## bubba52 (Sep 19, 2008)

*I have the same questions, see my post to Tweeter specs...*

today, in this same forum. let's figure this out and nail it once and for all. I can't believe how much time I have spent looking for these answers in different forums. There is plenty of good info, but it is usually for high end systems with multiple amps, which is not for me.


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## [email protected] (Sep 5, 2006)

Will get that exact information for you


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## bubba52 (Sep 19, 2008)

*The ohm specs are...*

The e39 5.25" mid-bass speaker is 4 ohm 
The e39 midrange speaker is 8ohm

still checking on the tweeter.


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## [email protected] (Sep 5, 2006)

The tweeter if I remember correctly is 4ohm. We will however add a capacitor back into the wiring so that it is properly matched to the factory system. Of course we will also add the plug and play connectors as well to make the installation much simpler


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## ZeroDfx (Sep 2, 2005)

*Upgrade implemented*

After poking around in multiple forums, I finally decided to install a set of CDT 51A's which included a 5.25" mid-bass and 1" silk dome tweeter for each front door. The swap was easy and the speaker wire tabs were an exact match/fit for the CDT's so there was no guessing re phasing. The sound improvement is striking! I wouldn't have imagined the stock system was "bad" until I heard the improvement just by this simple change. It's as if I was listening through ear-muffs with the OEM, and now I've taken them off. Famous last words: I should have done this a long time ago.

Nick


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## [email protected] (Sep 5, 2006)

Congrats on the upgrade! You chose some good drivers. We used to use some of their components! We still have some floating around here unopened as well!


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## 540iRunner (May 17, 2009)

ZeroDfx said:


> After poking around in multiple forums, I finally decided to install a set of CDT 51A's which included a 5.25" mid-bass and 1" silk dome tweeter for each front door. The swap was easy and the speaker wire tabs were an exact match/fit for the CDT's so there was no guessing re phasing. The sound improvement is striking! I wouldn't have imagined the stock system was "bad" until I heard the improvement just by this simple change. It's as if I was listening through ear-muffs with the OEM, and now I've taken them off. Famous last words: I should have done this a long time ago.
> 
> Nick


How'd the tweeter upgrade look? I have two non-functioning/blown tweeters and am thinking about making an upgrade, but want to maintain the factory look. Was it easy to install these tweeters and maintain OEM appearance?


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