Basic 'Hifi Speaker System' Upgrade

[TBDL]

The crappy sound system quality is getting to me now, I think it's time to drop in some replacement mid-range speakers, and probably an 'under seat' sub (behind the seats) before the sunny season starts.

I'm thinking of amping up the new speakers so I can get some decent quality, using a small four channel amp for the midrange, with built in hi-level input for ease as I have OEM headunit. I might start with replacement midrange speakers and a sub, then add the amp when I get annoyed with not hearing the best out of the new speakers.

To keep it simple:
4 x midrange speakers
2 x optional tweeters on the door speakers (I have no tweeters currently as basic system)
1 x 4 chan amp
1 x underseat sub

From what I can see on Real OEM, and reading up a bit, this is all I need to cover off. Any advice, things I am overlooking, or pointers to useful 'how to guides'?

Below are the notes I made for myself on the the 'hifi speaker system' in the E89. I think the midrange are all 10cm/4" but the part numbers do not actually state a size.

Rear speakers (Part 1 in diagram one)
Part number 65139240641 mid-range loudspeaker hifi

Door speakers (part 6 in diagram two)
Part number 65139240641 mid-range loudspeaker hifi (65139220751 tweeter for a companion of what to source)

Front woofers (part 1 in diagram two)
Part number 65139192367 Woofer

Diagram one:


Diagram two:

 

[B21]

Welcome a few folks have done various variations on this upgrade of the basic system..depends on how much you want to spend and your perceptions of ‘quality’ etc ..use the search function..there have been at least six different versions of this written up..

The majority are 100mm but BMW handed .,the woofers are 6” but again BMW handed..there most folks use an adaptor ring home made to use other 6” units

Some folks have retrofitted the 676/677 subs in the rear bulkhead..

 

[TBDL]

Thank you, @B21. I had a bit of a search, hard to see the wood for the trees to pick the 'right' information/how to guide.

I was thinking I'll use my 3D printer(s) to print a 3 to 4 hole adapter ring, if that doesn't go well then I'll buy some off the shelf. The woofers look a bit more of a pain to replace, hence I was going to leave them be and just whack in an under-seat sub to go alongside the bass (if it can be called that) from the current woofers.

I'm not looking to spend too much, it's just a weekend toy, but I think I can get the sub and speakers for <£200 for a decent set. Then maybe the 4ch amp on top, just browsing now to see what is available as it is a long time since I've bought and fitted car audio upgrades aside from the MMI units!

 

[AnubisZed]

This may be of help to you...
https://youtu.be/CQVyPZQuB9U?si=4xB-v7Z58-EaNYVG

I think you'll have issues fitting a sub under the seats, due to the lack of room.

The Vibe Powerbox amp is an option, especially as its plug-n-play with you current existing system. They also do a matching sub to work with it if you can find a good location.

As B21 says, some have upgraded to 676 or 677, and I'm now on the 677 OE system from the most basic version, but it's all down to money, and ive done my audio upgrades over a period of time

 

[B21]

Thank you, @B21. I had a bit of a search, hard to see the wood for the trees to pick the 'right' information/how to guide.

I was thinking I'll use my 3D printer(s) to print a 3 to 4 hole adapter ring, if that doesn't go well then I'll buy some off the shelf. The woofers look a bit more of a pain to replace, hence I was going to leave them be and just whack in an under-seat sub to go alongside the bass (if it can be called that) from the current woofers.

I'm not looking to spend too much, it's just a weekend toy, but I think I can get the sub and speakers for <£200 for a decent set. Then maybe the 4ch amp on top, just browsing now to see what is available as it is a long time since I've bought and fitted car audio upgrades aside from the MMI units!

Some folks have used the cheap B&O mini speaker clones of Ali express and have been pleased with them…good £ per octave value..

 

[matsmith749]

For even cheaper - get the speakers out of a mini cooper off ebay.

They are the same size, mount the same way (no drilling or surrounds to fab up), still made by BMW, and 5x as good quality. Immediately obvious once you look at them side-to-side.

I fitted them, it's a night & day change for £50.

The standard BMW speakers in the z4 are basicly the cheapest of the cheap, barely held together scraps of paper with flimsy surrounds & tiny magnets.

Change out the speakers first (as you will do that anyway) & listen - you may not need to go further.

 

[Envain]

Im also looking into this and found these guys = https://www.bavsound.com/products/bsd-s1-e89-hifi-stage-one-bmw-e89-hk
Not comfortable doing cabling/and rather not replace or add a amp (i believe mine comes with HiFi System Professional DSP package)

This seemed like everything needed to do direct drop in replacement without the need to mess with wiring. Quality though compared to other brands that im not sure.

Ive looked through a few posts here, and here https://z4-forum.com/forum/viewtopic.php?t=151194 plenty of options it seems

 

[Reamesy]

For even cheaper - get the speakers out of a mini cooper off ebay.

They are the same size, mount the same way (no drilling or surrounds to fab up), still made by BMW, and 5x as good quality. Immediately obvious once you look at them side-to-side.

I fitted them, it's a night & day change for £50.

The standard BMW speakers in the z4 are basicly the cheapest of the cheap, barely held together scraps of paper with flimsy surrounds & tiny magnets.

Change out the speakers first (as you will do that anyway) & listen - you may not need to go further.

Do you have part numbers for the mini speakers please?

 

[The.Analyst]

Im also looking into this and found these guys = https://www.bavsound.com/products/bsd-s1-e89-hifi-stage-one-bmw-e89-hk
Not comfortable doing cabling/and rather not replace or add a amp (i believe mine comes with HiFi System Professional DSP package)

This seemed like everything needed to do direct drop in replacement without the need to mess with wiring. Quality though compared to other brands that im not sure.

Ive looked through a few posts here, and here https://z4-forum.com/forum/viewtopic.php?t=151194 plenty of options it seems

They’ve probably tackled the normal problem that most aftermarket speakers need more drive than the stock amp can deliver with more efficient speakers

The US based suppliers normally assume you’ve got a 676/677 system not the basement version

 

[Envain]

Yeah it seems the easiest to get atleast for the US for direct drop in, from research it looks like bw≥hk≥BO and the Bo ones seem all out of stock everywhere.

The Eton b100w neos look good too, but again issues for US delivery... though that's now a whole other can of worms

 

[B21]

Yeah it seems the easiest to get atleast for the US for direct drop in, from research it looks like bw≥hk≥BO and the Bo ones seem all out of stock everywhere.

The Eton b100w neos look good too, but again issues for US delivery... though that's now a whole other can of worms

The Eton stuff is very good ..used it a couple of times…but..does require plenty of amplification that stock units don’t have…well in a convertible

 

[TBDL]

Thanks for all the feedback and comments, missed the notifications as they went to junk

The MINI speaker tip is a good one that I did not know of.

For now I’ve ordered 4 x In Phase 4” XTC coaxial speakers, the XTC10.2. They seem good from reviews, and I got a fair price at £27 a pair. I like the directional tweeters in them too as an added bonus.

I’m printing number three of four speaker adapters as I type. Hoping they don’t add too much height, causing the speakers snag the grills. We’ll see when the speakers arrive, I’ll work it out from there.

I’ll checkout the Amp AnubisZed mentioned; hoping the speakers alone might be OK without an amp, we’ll see. I’m happy enough fitting one as I used to play about with car audio a lot ‘in my youth’, tapping inline for each speaker should be straightforward.

As for sub, I was looking at the In Phase USW300 as its only 7.5cm deep so can mount it behind (not underneath) the driver’s seat without any issue. This sub purely on the fact it’s good value (<£90), matches the speaker brand, has hi-level input so I can just tap into a rear speaker as I replace them, has good reviews. Should add a nice little bit of bass above the headunit driven upgraded speakers, is my thinking.

I’ll update when the speakers arrive, see how they fit. Then I’ll get the sub likely after I’ve tried just the speakers.

 

[AnubisZed]

.....

I’ll checkout the Amp AnubisZed mentioned; hoping the speakers alone might be OK without an amp, we’ll see. I’m happy enough fitting one as I used to play about with car audio a lot ‘in my youth’, tapping inline for each speaker should be straightforward.
....

With the correct BMW one no need to tap into anything...
https://amzn.eu/d/5J5kffy

 

[TBDL]

.....

I’ll checkout the Amp AnubisZed mentioned; hoping the speakers alone might be OK without an amp, we’ll see. I’m happy enough fitting one as I used to play about with car audio a lot ‘in my youth’, tapping inline for each speaker should be straightforward.
....

With the correct BMW one no need to tap into anything...
https://amzn.eu/d/5J5kffy

Oh, nice, I did not realise it was that compatible! Thanks for the link, aside from the fact I now want to buy it

 

[TBDL]

With the correct BMW one no need to tap into anything...
https://amzn.eu/d/5J5kffy

I have an MMI already in place, into my CIC pro screen. I’m thinking (1) will this cause any issue with the plug and play of the amp, I think not as the CIC just taps into the mouse and the screen from memory of when I fitted it (2) could the RCA input of the amp be used with the MMI, somehow, so I don’t need lower quality Aux from the MMI to the CIC? I’m guessing not, as only 4 channels would pickup the sound, and there are 6 channels include the footwell subs.

 

[Chippie]

there are 6 channels include the footwell subs.

The footwell and door speakers are on the same channels, so only 4 channels with the rears

 

[TBDL]

The footwell and door speakers are on the same channels, so only 4 channels with the rears

Ahhh, I did not realise this, thank you! So that Vibe Amp would actually boost the woofers too. Even more tempted to just buy it.

 

[TBDL]

Ok, I ordered the Amp already. The plan of seeing if the speakers alone would be fine has backfired in < 2hrs. I blame Dave

So I have now on the way:
1 x Vibe POWERBOX65.4BMW3
4 x In Phase XTC10.2
4 x BMW speaker connector to spade connector adaptors, just to save any chopping at all of wires, £4.10 for all four on Ali Express, let's see what they are like if/when they arrive

Plus I'm 3D printing 4 x speaker fitting plates/adapters.

I doubt I'll need anything else with these upgrades, slimline sub idea can go on the back burner for now. Only possible thought is some sound deadening material for the doors, but that makes an otherwise easy installation suddenly a lot more of a pain, so I do not think I will bother.

Should all arrive by next weekend, the wires are the only ones that may take longer, so let's hope in a week's time I'll be fitting them.

 

[AnubisZed]

I have an MMI already in place, into my CIC pro screen. I’m thinking (1) will this cause any issue with the plug and play of the amp, I think not as the CIC just taps into the mouse and the screen from memory of when I fitted it (2) could the RCA input of the amp be used with the MMI, somehow, so I don’t need lower quality Aux from the MMI to the CIC? I’m guessing not, as only 4 channels would pickup the sound, and there are 6 channels include the footwell subs.

1) No, as your current mmi plugs in via the iDrive controller then there will no issue here
2) In short, no!

Ok, I ordered the Amp already. The plan of seeing if the speakers alone would be fine has backfired in < 2hrs. I blame Dave

So I have now on the way:
1 x Vibe POWERBOX65.4BMW3
4 x In Phase XTC10.2
4 x BMW speaker connector to spade connector adaptors, just to save any chopping at all of wires, £4.10 for all four on Ali Express, let's see what they are like if/when they arrive

Plus I'm 3D printing 4 x speaker fitting plates/adapters.

I doubt I'll need anything else with these upgrades, slimline sub idea can go on the back burner for now. Only possible thought is some sound deadening material for the doors, but that makes an otherwise easy installation suddenly a lot more of a pain, so I do not think I will bother.

Should all arrive by next weekend, the wires are the only ones that may take longer, so let's hope in a week's time I'll be fitting them.

An option for the woofers, yours will be the standard basic versions (pt No/ 9181819), you could just fit the original upgraded versions as fitted to the 676/677 (pt No/ 9192367). They fit straight in, no adaptors or wiring mods to do There is quite a substantial weight difference between them!

 

[TBDL]

An option for the woofers, yours will be the standard basic versions (pt No/ 9181819), you could just fit the original upgraded versions as fitted to the 676/677 (pt No/ 9192367). They fit straight in, no adaptors or wiring mods to do There is quite a substantial weight difference between them!

Great advice as always, Dave, thanks! I’ll keep an eye out for a pair going cheap… I might also take a quick look to see how easy it might be to design and print an adapter for an aftermarket woofer. My 3D design skills are low, but I can do basic shapes etc. so it’s probably possible.