[blau3er]

Hi all,

Starting this thread to document the retrofit journey of the OEM Bang & Olufsen Hi-End audio option into my F31.

This option was never available for F3x platform, instead it was reserved for 5, 6, 7, X5 & X6 models only in the F generation.

Ever since retrofitting BMW Individual Audio into my previous E91, I have felt the factory fitted Harman Kardon in my F31 didn't have the same punch. I am an OEM+ kind of guy and all my mods are done with that mindset and I wanted something as good as, if not better than my Individual Audio experience.

Aftermarket options with MOST adapters and the need to 'tune' a systems DSP just does not appeal to me and I like to do things that others wouldn't. With that in mind, I've been keen to do this with my F31 for some time.

I've made tentative posts before seeking any examples of this being done, but it's apparent the knowledge of how to do this and any examples of it being done before are distinctly lacking. It's probably a step too far for most people - which I totally understand!

Over the last few months I have devoted quite a bit of time and effort to research this in detail. This has led me into speaking to some very knowledgeable people in Germany and Eastern Europe who have helped me out tremendously with lots of helpful information and the supply of some difficult to find parts. I have also spent many hours on newTIS comparing the two systems wiring diagrams side by side to work out exactly what is needed to carry out the Bang & Olufsen retrofit in the OEM way.

The first task was to source a complete B&O set up, which I purchased from a BMW Test Car dismantler in Germany - the car was a 2016 model F06 M6 and had covered only 12 miles - so the parts are essentially 'new old stock'.



The next job was to put all of the research to good use and procure all of the necessary parts, cables, connectors, pins etc to make things work.



I will be posting a detailed PDF document that I have been writing explaining all the details of the retrofit in due course, however the salient points of what is needed is as follows:

• The mid-range and under-seat bass speakers continue to be supplied by the existing HK wiring loom that connects to the new B&O amp and the pin-outs remain the same here.
  
• The B&O tweeters each have their own separate channel, which requires a new wiring loom to be made, and the loom connects back to the new B&O amp via an additional 32-pin connector that does not feature on the HK amp.
  
• The power source is taken directly from a 50 amp fuse blade in the rear battery distribution box, rather than the 40 amp location in the rear fuse box as it is on the HK system. This requires a new power loom to be made, using upgraded 10mm2 cabling. The earth cable also needs to be changed to 10mm2.
  
• The B&O amp uses an additional microphone connection, which is to be ran into the existing mic location, where the microphone itself is replaced with a dual function mic.

I will commencing the work with the help of my good friend Wibbles in the coming days, and as things progress I will update the thread. Once it is in and working I will finalise the PDF doc and happily share it with anyone who is interested.

Oh, and just to head off the comments - yes..... I am aware that aftermarket options are 'better', however I just don't have any interest whatsoever in an aftermarket system and for me its about retrofitting the best BMW offered for the F platform, all done exactly how it would have been done had B&O been optioned on a F3x car.

[Billfitz]

Originally Posted by blau3er

I am aware that aftermarket options are 'better',

Not to the extent that advertising would have you believe. I would go with a Match Up amp for the DSP capabilities, but if you're not into doing your own system tuning then the B&O is likely the best you're going to find. The B&O speakers are probably as good as you'll find also, unless you need the deep bass that only a very few aftermarkets can deliver. If you're not into EDM and the like that probably won't matter to you either.

[damack]

I assume the factory does some sort of tuning on the internal dsp to suit the vehicle. Wouldn’t the B&O amp be set up for completely different acoustics?

[Billfitz]

They do, but there's not going to be that much difference between BMW sedans. The B&O has some EQ adjustments, not enough to be sure, but it's still better than none. FWIW they claim to have done 400 hours of testing to determine the best DSP pre-set, but that's just so much hogwash. With modern test equipment nothing that needs to be done would take more than four hours.

[Samir72]

Very interested to how this turns out, you F31 will sound as stunning as it looks.


I upgraded all my HK mids and tweeters to B&W’s recently to very good effect, couldn’t find the diamond tweeters for a good price up front so went with the aluminium ones all round.

[blau3er]

Originally Posted by Billfitz

Not to the extent that advertising would have you believe. I would go with a Match Up amp for the DSP capabilities, but if you're not into doing your own system tuning then the B&O is likely the best you're going to find. The B&O speakers are probably as good as you'll find also, unless you need the deep bass that only a very few aftermarkets can deliver. If you're not into EDM and the like that probably won't matter to you either.

Interesting, I thought based on your extensive experience with the aftermarket stuff (and lots of very informative posts, may I add!) that you would be rather critical of the B&O option.

To be honest, I am an OEM guy and I just love the idea of having something in the car that nobody else would / will have - and if it sounds as good as my old Individual Audio (which I know it will, and will be better than) then I will be happy!

It has been a headache though sorting out all the research and working out how to go about powering it in the same way as BMW have done in the actual F generations models where this was an option.

In terms of bass - I do like EDM, and R&B etc which is bass heavy - but I am not looking to give myself tinnitus either!

[blau3er]

Originally Posted by damack

I assume the factory does some sort of tuning on the internal dsp to suit the vehicle. Wouldn’t the B&O amp be set up for completely different acoustics?

Originally Posted by Billfitz

They do, but there's not going to be that much difference between BMW sedans. The B&O has some EQ adjustments, not enough to be sure, but it's still better than none. FWIW they claim to have done 400 hours of testing to determine the best DSP pre-set, but that's just so much hogwash. With modern test equipment nothing that needs to be done would take more than four hours.

As Billfitz mentions, there are profiles for each body designation. My donor amp is from a F06 6er Gran Coupe - so a 4 door saloon. The closest profile for a F31 would most likely be that of the F11 5er Touring - so that can be coded to the amp if required.

[blau3er]

Originally Posted by Samir72

Very interested to how this turns out, you F31 will sound as stunning as it looks.


I upgraded all my HK mids and tweeters to B&W’s recently to very good effect, couldn’t find the diamond tweeters for a good price up front so went with the aluminium ones all round.

Thanks!

Interesting that you went down the Bowers & Wilkins route and not the Bang & Olufsen - was there any reason for that?

It would be interesting to hear what results you got from just changing the speakers out and maintaining the HK amp.

Next step would be to probably change your under-seats?

I currently have everything still as HK in mine, but with the addition of B&O under-seat woofers and the difference was very noticeable. It has given me a taste of what's to come once the retrofit is completed!

[cfm56d7b]

Great project. Very interested in the results. Will follow all updates.

[NealfromNZ]

Having done a recent speaker cable / most runs it is time consuming, but straight forward. I did find for some reason that getting connector pins into the speaker section of the door connectors on the cabin side difficult for some reason ( might have been my initial crimps ) . Ended up using spare positions in the main connector. Would recommend some basic sound treatment for the doors whilst you’re got the door cards off. Even modest treatment gets good results. Also tesa tape on the door clip mounts stop them vibrating. Virtually no vibration from the door cards now..

Interesting what your saying on HK to B&O underseat woofer change. Finding the HKs a bit average even with giving them more power and having full dsp control. Have been thinking B&W or aftermarket to replace them with.

[Billfitz]

Originally Posted by blau3er

Interesting, I thought based on your extensive experience with the aftermarket stuff (and lots of very informative posts, may I add!) that you would be rather critical of the B&O option.

My only misgiving is that it's seriously over-priced. There's no excuse for a system that expensive not having fully controllable DSP, which you can add to conventional systems for $165. https://www.parts-express.com/Dayton...500?quantity=1

For all the money that any of the BMW systems cost there's no excuse for them to be still using twenty year old technology. Oddly enough it's only their speakers that aren't obsolete.

[Samir72]

Originally Posted by blau3er

Thanks!

Interesting that you went down the Bowers & Wilkins route and not the Bang & Olufsen - was there any reason for that?

It would be interesting to hear what results you got from just changing the speakers out and maintaining the HK amp.

Next step would be to probably change your under-seats?

!

The main reason I went with the B&W’s was my love of there home speakers having owned a few sets in the past both 2ch and multi channel 7.1.

And also who doesn’t love those Kevlar woven cones.

I have never really been blow away with B&O sound quality and always felt t was more design led products.

I find It really gave me a noticeable upgrade in sound quality even just using to HK amp. Did half the car at time to try to give myself a clear opinion on them.

Did not go into changing the underseat subs as would need to add an amp to run them and as you know that when it starts to get expensive with most optical connections.

It’s Not as good in 2 ch as the gladen mosconi set up I had in my E90 but I really do enjoy logic 7 for Music playback and use it for everything, i also use DTS X at home for music.

Are you also changing the centre channel dash speaker?

[blau3er]

Originally Posted by Billfitz

My only misgiving is that it's seriously over-priced. There's no excuse for a system that expensive not having fully controllable DSP, which you can add to conventional systems for $165. https://www.parts-express.com/Dayton...500?quantity=1

For all the money that any of the BMW systems cost there's no excuse for them to be still using twenty year old technology. Oddly enough it's only their speakers that aren't obsolete.

I think all told, this will cost me £1300-£1500 depending on how things pan out! I have a few bits to sell (spare B&O amp and a set of under-seats), and if I get decent money for them, it might be even less. I know that's probably still close to (but I think still less than) the cost of an aftermarket set up which would be 'better'.

Either way, I am looking forward to it going in!

[blau3er]

Originally Posted by Samir72

The main reason I went with the B&W’s was my love of there home speakers having owned a few sets in the past both 2ch and multi channel 7.1.

And also who doesn’t love those Kevlar woven cones.

I have never really been blow away with B&O sound quality and always felt t was more design led products.

I find It really gave me a noticeable upgrade in sound quality even just using to HK amp. Did half the car at time to try to give myself a clear opinion on them.

Did not go into changing the underseat subs as would need to add an amp to run them and as you know that when it starts to get expensive with most optical connections.

It’s Not as good in 2 ch as the gladen mosconi set up I had in my E90 but I really do enjoy logic 7 for Music playback and use it for everything, i also use DTS X at home for music.

Are you also changing the centre channel dash speaker?

I'm not sure what the B&O cones are made of, but they are certainly woven. I don't think its B&O that actually make some of the speakers anyway - certainly in the case of the under-seat woofers, they are made by LPG / Paragon Acoustics.

I will be changing the centre speaker yes, but not with the motorised version - as it obviously does not fit into the F3x housing. Instead I am using a separate B&O mid-range and tweeter.

No amp is/was required to run the B&O under-seats with the factory HK amp, and the difference is noticeable.

[Samir72]

Originally Posted by blau3er

I will be changing the centre speaker yes, but not with the motorised version - as it obviously does not fit into the F3x housing. Instead I am using a separate B&O mid-range and tweeter.

No amp is/was required to run the B&O under-seats with the factory HK amp, and the difference is noticeable.

Aha that’s great that the B&O underseats do not require an amp upgrade, and selling that should off set the cost nicely OEM amps sure are not cheap.

Sounds like you are off to great start with this and a very nice OEM+ upgrade.

[Billfitz]

Originally Posted by blau3er

No amp is/was required to run the B&O under-seats with the factory HK amp, and the difference is noticeable.

If that's the case I expect the B&O are lower impedance than the 8 ohm H-K. If so that may or may not be a problem. The only logical reason for the H-K woofers being 8 ohm is that the wiring won't handle the higher current load of 4 ohm. Chances are current B&O drivers are made by one of the various Harmon subsidiaries, as B&O has been a Harmon company since 2015.

[blau3er]

Originally Posted by Billfitz

If that's the case I expect the B&O are lower impedance than the 8 ohm H-K. If so that may or may not be a problem. The only logical reason for the H-K woofers being 8 ohm is that the wiring won't handle the higher current load of 4 ohm. Chances are current B&O drivers are made by one of the various Harmon subsidiaries, as B&O has been a Harmon company since 2015.

All my research suggests that B&O are 8ohm, the same as the HK ones are. What I noted when I fitted the B&O subs (with everything else remaining factory HK) was more noticeable bass punch. Obviously it’s not a scientific reading, but the most obvious sign of this is how much the rear view mirror now distorts!

The HK under-seat wiring is 2.5mm2 and so is the factory B&O wiring - so no difference there, despite the HK amp sending 125w to each sub and the B&O sending 250w.

I’m no audio expert though, but that has been my experience.

[Billfitz]

Being an acoustical engineer I always follow the advice given by former president Ronald Reagan: Trust, but verify. Trust what your ears are telling you, but verify with measurements.
As to the wattage comparison, power can be increased by both increasing current and increasing voltage swing. Increasing current requires a larger wire gauge to handle it. Increasing voltage swing does not.

[NealfromNZ]

Originally Posted by Billfitz

If that's the case I expect the B&O are lower impedance than the 8 ohm H-K. If so that may or may not be a problem. The only logical reason for the H-K woofers being 8 ohm is that the wiring won't handle the higher current load of 4 ohm. Chances are current B&O drivers are made by one of the various Harmon subsidiaries, as B&O has been a Harmon company since 2015.

If the wiring gauge is the same as my f80 the OEM loom should have 2.5mm2.

[blau3er]

Originally Posted by Billfitz

Being an acoustical engineer I always follow the advice given by former president Ronald Reagan: Trust, but verify. Trust what your ears are telling you, but verify with measurements.
As to the wattage comparison, power can be increased by both increasing current and increasing voltage swing. Increasing current requires a larger wire gauge to handle it. Increasing voltage swing does not.

I wish I knew the difference, but I would be lying if I claimed I did! All I can say is that the cable thickness for the mids (0.75mm2) and the bass (2.5mm2) is the same between the HK and B&O set ups - yet the amp is twice as powerful (625w vs 1200w).

In addition, the B&O uses 0.5mm2 for the individual tweeter channels.

Originally Posted by NealfromNZ

If the wiring gauge is the same as my f80 the OEM loom should have 2.5mm2.

Correct - its 2.5mm2.

[blau3er]

UPDATE - 30/07/23

Stage 1 - running in the new power source.

With Wibbles doing the bulk of the work, we got the new power source laid into the car today. I felt this was probably the biggest job, as its a whole new power loom that is required for B&O when compared to the HK. To do this, all of the rear boot panels need to removed - so we decided to tackle this first to get it out of the way.

Attached to this post is the power section the retrofit document that I have been creating, which clearly outlines the differences between the power requirements of HK & B&O. It also contains all of the required p/no's for the terminals and connectors needed to create the wiring. This is part of the complete document that I will eventually upload to the first post once everything has been completed.

Firstly, I assembled the necessary replacement battery fuse box, the terminals (MAK8, LSK8 and ground ring) and the plastic connector blocks.



As described in detail in the PDF, you need to change the battery fuse box to provide a spare fuse blade to take the new power from, then run the 10mm2 cables through the factory trunking and into the amp location. The 10mm2 earth cable is terminated on a short run at the Z10*8B location.

Crimping these sized connectors onto the 10mm2 cable can be tricky and there is a distinct lack of information available as to the correct tool that is required for the job, and the OEM BMW tool is several thousand pounds - meaning thats a no-go! After many hours of searching I settled upon the IWISS iCrimp IWS-5100A crimping too, which provides enough leverage for the job.



Once the required connectors are crimped on, and the cables are routed - its job done for the power. I'm leaving the interior dissembled for now and hopefully there will be an opportunity to start the tweeter cable runs next later on this week.

Here are some photos showing todays progress...

Interior panels out, and new wiring in.



The new Z3 power distribution fuse box. The blue circular sticker that I added denotes the new 50 amp fuse location that is needed.





The new A52*4B connector ready to plug into the B&O amp.





The new location for the 10mm2 B&O earth cable. Located at the Z10*8B ground connector.



Passenger side (my car is RHD) wiring routing, using OEM cable trunking locations.





Drivers side wiring routing, using OEM cable trunking locations.

[NealfromNZ]

Loving the factory attention to detail.