2016 F80 base audio upgrade, the start

[NealfromNZ]

Reprogramming audio to use Digital Most

My M3 had base audio with amplifier duties covered by the ASD module. Basically a 25watt x 4 setup. It looks to be feed via an analogue signal from the NBT Evo.

The Mobridge 8.1.1 amplifier has 6x75 rms , 2x150 rms and 1x 400rms power wise , but specs are conservative going by the power rails used and a run through that Mobridge gave me. The Mobridge is a digital only amp and emulates a Most amplifier on a Most ring ( like HK amp ) For my base audio system the NTB unit needs coding to turn on Most digital audio.

For F8x / F3x running NTB evo no flashing is needed , just coding. There is at least a couple of ways of doing this. One is esys and the other is bimmercode expert mode. I went with bimmercode as it’s easy phone app to install and automatically takes a backup before coding is done. It can run with a number of ODBII dongles. I went with the latest MHD universal wifi adapter as it’s reported to be fast and easy to connect to , basically just connect to its wifi ssid as you would with any wifi network.

Coding is straight forward , you just need in expert mode code Harman Kardon in one menu and enable Most audio in another. I did a forced reboot by pushing the console volume button down for 30 seconds and the NBT rebooted. I then locked the car to put into sleep mode and then unlocked. At which point the Mobridge amp joined the Most digital network and was ready to configure.

I’ll go into Mobridge configuration later , but can say it’s a nice straight forward DSP to configure and has great flexibility in tuning volumes down for PDC / NAV / Chimes etc.

Below are the screenshots for bimmercode after expert mode is checked.



EDIT 27-12-2023

In this project I replaced the ID4 idrive unit with IDrive 6 hardware. At that point BimmerCode would not allow any coding of the new unit ( needed MOST and Camera module coded ).

Replaced coding tool with Bimmer Utility and enet cable. I haven’t tried it with the MHD wifi adapter yet.

[NealfromNZ]

Have put a base tune into the Mobridge. Tuning by ear at this point. Need the door speakers to have some run-in time and expecting the midbass and tweeter to free up a bit. But sounding quite good.

Tuning for a stereo image with rear fill. Using an old 10 inch sub at the moment as haven't finished mods to subwoofer box.

Focal K2 Tweeters 3.5khz to 20khz
Focal Es100k Door mids 150hz to 3.5khz
Harman Kardon 8 inch underseat 55hz to 150hz
Boston 10 inch subwoofer 20 -55hz

Mobridge DSP interface is easy to use. Well set out and simple to configure.

First picture is front speakers.
Second is initial RTA which is is roughly following intended house curve.

[NealfromNZ]

Couple of weeks now of running now so detailed tuning over the coming weekend

But system is a complete transformation with fine tuning to go.

The Mobridge 8.1.1 is a very capable amplifier with excellent clarity and power. Even with my backup 10 inch sub when turned up will absolutely thump out bass lines with authority and detail. Expecting further gains when I replace with my old Boston Acoustic SPG555 / Passive radiator combo.
An excellent one box solution to cover all doors ,underseat and trunk plus DSP. And works in well with all the usual BMW functions. Especially like the ability to drop PDC volume lower over what the idrive will let you do. Very important when adding power to the speaker system. Without it PDC screams at you.

Midbass via Focal Es100k is nice and detailed with a great sound stage width. Focals have good dynamics for a 100mm speaker, can go quite loud and remain clear at higher volumes.

K2 Focal tweeters are very detailed and the combo soundstage image sitting slightly above the dash board ( BMW has got the factory tweeter pointing mounts right !) . Running front pair active I've reduced them around -6db to match midbass. Expecting these to improve more as they finish running in. Would describe as a forward sounding tweeter.

Has been worth putting Focal Es100k Components into rear doors as well, even running with passive crossovers it leaves rear seats with a nice detailed soundstage and no tonal difference between front and rear speakers when I have these running at same volume levels as fronts.

Harman Kardon 8 inch on Mid bass is getting plenty of power , but the HKs aren't up to scratch covering 60 -150 hz in my onion. Would class as "ok" and slightly muddy but one positive is they can take a considerable amount of power. Did try them down to 30hz to see what they would do but the output drops quickly below 50hz. These will be replaced.

Don't run a center channel , but not my thing. there is a spare RCA out on the Mobridge should this be needed , but I don't like center channels on music.

So basically the system can cover the detail for Classical music , Has impacted for EDM / Prog music , can do Hiphop with plenty of lows and the tweeters can do the crisps highs required in metal or drums.

[Andrew_za]

Just wanted to say im really enjoying the thread. Going to be doing something similar in my F36, except use an Helix SDMI25 to convert the MOST25 to SPDIF, and a Helix V Twelve as the amp for the speakers (and a cheaky little HD750/1 for sub duties when that is installed). Was searching for someone who had activated Most on a base audio spec car and your post has helped immensely

[NealfromNZ]

Originally Posted by Andrew_za

Just wanted to say im really enjoying the thread. Going to be doing something similar in my F36, except use an Helix SDMI25 to convert the MOST25 to SPDIF, and a Helix V Twelve as the amp for the speakers (and a cheaky little HD750/1 for sub duties when that is installed). Was searching for someone who had activated Most on a base audio spec car and your post has helped immensely

Sounding like the makings of a great system with plenty of power in tap !

Let us know what you do for underseat woofer replacement an your impressions please. Looking for a replacement that’s tighter in the 50 ish to 150hz range.

[Andrew_za]

Originally Posted by NealfromNZ

Sounding like the makings of a great system with plenty of power in tap !

Let us know what you do for underseat woofer replacement an your impressions please. Looking for a replacement that’s tighter in the 50 ish to 150hz range.

So i have the stock 6inch speakers atm, but going to change them out to the HIFI version and then the HK version (want to see all variants and measure responses etc). After that im probably going to try the Steg BM8II or DLS CRPP-BMW1.8. Also have a pair of DLS Scandinavia 6/2 which i want to try.

Sub duties in the future will be curtousy of a Morel Ultimo 12

[NealfromNZ]

Sounds like nice combos coming. I did measure both the 6.5s & 8s. With the base audio the factory eq 6.5s results were interesting. Quite well optimised considering low available power and size.

[Andrew_za]

Do you perhaps have the RTA evaluation of the two (or more) that you have tried?

[NealfromNZ]

Originally Posted by Andrew_za

Do you perhaps have the RTA evaluation of the two (or more) that you have tried?

I’ll have a look at my Rew saves to see if I still have the 6.5s. It was surprising flat to 45hz but obviously has quite a bit of eq applied.

Here’s the HK running flat with no eq. Even with cabin gain it wouldn’t follow a target curve without quite a bit of eq at the lower end. However it’s quite usable above 60 hz to 200 hz in a 4 way setup.

[NealfromNZ]

And here is the HK played at the same volume 55-150hz filers but with a small enclosure 10 inch sub running to 55 down.
Easier to hit a target curve with little eq and sound wise far more balanced at the lower end.

[NealfromNZ]

Underseat woofer replacement of Base audio / Harman Kardon

I think I’ve moved backward and forward on this over the last year and there is a long thread running on the subject that in the F30 Nav / audio thread mainly centred around underseat replacement options. Bill that is on that thread points out tradeoffs with the various speaker choices that and pops them into a model to determine behaviour. Bill can articulate the reasons well and suggests that a earthquake sw is better suited if you have more power and want to go lower. Above a certain point in the frequency range the HK will go louder so it’s all about trade offs. I didn’t consider the earthquakes as seen differing TS specs suggesting very high Q ( boomy )

In other online forums other options come up for mid bass. At the high end Focal Utopias come up a but well beyond my hobby budget and Im not building an audio comp car. Also ADw800neos or C8s when used as midbass from 80 -90hz up and a trunk sub. But it’s unclear to me if they would fit under a f80 seat without spacers. Anyway, my advice is to listen to choices if you can or if you can’t take advice from someone you trust that had a particular model.

Harman Kardon 8 inch

The Harman Kardon units are quite efficient but at 8 ohms need an amplifier that can deliver voltage to power them up. So with some of the aftermarket amplifiers the 8 ohm load poses a load where the don’t make their rated 160 rms @ 2ohms It can be more like 80 watts rms or lower where the impedance curve rises rapidly as the speaker goes below 50hz. Basically hard to get serious bass out of them. However Benefits of the HK and hifi enclosures is they have a larger internal volume, larger port into the side sill area and are considerably denser.

I’ve run the Harmans for past three weeks a spent a few hours tunning them in. With an estimated 144 rms available into 8 ohms conclusion was whilst they can go quite loud from 70 -150 hz they didn’t have the tightness or impact I’m after. They are at their best running anything in 60 - 200hz range in my opinion.


Woofer choice, criteria is to cover 50- 150 hz with detail and not loose it at higher volumes.

Stereo Integrity TM8
Good power handling / price point /volume and reputation for quality. However too close to seat rails on maximum excursion based on 38mm of room between enclosure face and seat rail. Rail bolt washers could sort , but safety aspects to consider.

ESB audio BMW Sub one
biggest voice coil for front venting motor and excellent 60hz plus efficiency, low QTC . Couldn’t get in New Zealand via zapco dealers without paying an absolute premium

Intergal Audio 8 inch
High power handling, quality R&D and well thought out products , no specs though , but love company ethos. If I wasn’t into diy audio hobby the whole system is quite compelling . If it weren’t Timezone issues I would have called for more info as the IA8a are run in my target lower frequency range when combined with trunk sub.

Morel BMW Sub high power, mid QTC value looking good for acurate bass controlled, needs lots of power to get volume though as lower efficiency. 2 ohm load means Mobridge can deliver considerable power so not concerned with efficiency. Postage low from neighbouring country

Secondhand BMW B&W . No specs but good reputation and can take considerable power. 8 ohm rating so needs high voltage amp to get best out of them, More expensive second hand than other options with freight and risk of knockoff clones being sent when buying.

Edit
Adding in jmciver choice as he runs these in mid bass suites on his car ( check out his excellent build thread ).
Audison APBMW High powered QTS 0.65 , 2 and 4 ohm version depending on your amp choice.

At the end of the day I would have been happy with any of the above choices but I’ve put money on the Morels. This has been a combo of price landed in NZ and conversing with Phazer of Mobridge (runs them in his BMW ) and TS specs that make sense for my install.

I’ll graph them compared the HK when they arrive and post results

.

[NealfromNZ]

Originally Posted by Andrew_za

Do you perhaps have the RTA evaluation of the two (or more) that you have tried?

Here's the RTA for Bass Audio with 6.5 underseat woofers assuming F80 ASD as amp and Idrive coded to Stereo.

This was -18d noise file played into bass audio system. It actually loosely follows a target curve and the bass below 50hz wasn't expected. Obviously, some boosting occurring at either end of the audio spectrum. Tone controls flat.

[Andrew_za]

Thanks a lot mate. Do you perhaps have the RTA with 1/12 filtering? If not, no worries at all!

[NealfromNZ]

[QUOTE="Andrew_za;30366970"]Thanks a lot mate. Do you perhaps have the RTA with 1/12 filtering? If not, no worries at all!

Sorry , this was the only Rew app save that I took at time. Should have taken a iPhone screen shot using the app “Spectrum” at the time as it graphs nicely although not sure about if iPhone 13 has been calibrated.

I’ll install one Morel when they arrive and do a compare with HK running with no eq and a 30hz HPF (at same idrive volume and then at same SPL for curve)

Expecting the following based on modelling

HK to be more efficient
Morel to have more bass output below 60hz to its 30hz FS point
Morel to have a slightly higher SPL average at its maximum rated power.
Morel to be tighter on Bass with Its TS specs, QTS of 0.57 verse HK at around 0.7

And the subjective assessment, does it sound better to my ears 😀

Hopefully they are worth the money !

[Andrew_za]

Im really keen to see the difference between the two! Morel is around £720 a set here in the uk and the ESB is £517 a pair. The ESB really look nice ngl. The plastic basket of the morel kind of puts me off considering the price!

[NealfromNZ]

Originally Posted by Andrew_za

Im really keen to see the difference between the two! Morel is around £720 a set here in the uk and the ESB is £517 a pair. The ESB really look nice ngl. The plastic basket of the morel kind of puts me off considering the price!

I’ll take some photos and advise how sturdy they are. If you have the option to listen to both would be interesting to compare as well.

But other than the examples you’ve post the majority of top motored drop in style BMW replacements have plastic baskets. Even the B&W factory options.

ESB are on special in Europe ( Ahifi $300e ) and ironically they sell both the ESB & Morels. ESB has massive 63mm voicecoils so suggests they can take lots of power and deal with it and high efficiency. Just with that low Q value the lower frequeny I’d set a HPF with a steep curve.

Ironically Underseat woofer prices in NZ are all over the place.

Eg
HK second hand $420
Focals ( on special and local ) $700-800
Imported
morel $1050 ( via Au )
Esb $1250 ( via USA )
IA $1000 ( via USA )
B&W $1100 secondhand via eBay

[jmciver]

Another option that think works well in the group you mentioned are the Audison 8”, 2 ohm underseat woofers. I bought them, based on their specs, specifically with the intent to use them as mid bass speakers and to pair them with a trunk sub. Worked out nicely, at least to my ears …

[NealfromNZ]

Wrapped the subwoofer enclosure yesterday. Just reminds me that working fabric and glue isn’t my think 😀


I wasn’t able to get / find fabric into match trunk carpet. Used a leatherette vinyl on the front baffle and Penn pro audio heavy speaker carpet I found last time the lighter speake carpet became tatty looking overtime.



The box is 1 cubic foot. Sides are 18mm mdf and the front baffle is double layered to 36 mm to stop any flex. Due to the weight of box and sub I’m putting in metal internal brace and a m8 rivnut as a anchor plate. The sub will bolt in to the rear trunk anchoring points which I’ve modded to include l brackets and M8 thumb screws. Makes it safer from an accident POV. The sub can be removed when needed.



The subwoofer is a 2 ohm 1000 rms Boston Acoustic SPG 555 from the late 2000s . I brought it as it has a good tradeoff on accurate Bass and was capable of SPLS in the high 130s in a car. Very high at the time for its size. It has a replaceable voice coil and surround.

It’s augmented with a passive radiator cone. A passive radiator makes the sub behave more like it’s in a ported enclosure but in an box that is typically the same volume as you’d run for seaked. So sound wise you get a sealed enclosure tight sound, Extra bass from the sub as if it was ported in a box that’s only 1 cubic foot rather than 1.75.
Only downside of passive radiator setups is that the group delay spikes at the resonance frequency of the passive is hit . But at 23 hz I’m not worried about group delay 😀 So bass is quite tight down to this point.

As the Mobridge uses a pair of outputs on its subwoofer channel. This is no doubt to deliver the current requirements through its patch hatness. I ended up running 1.5mm2 x 2 to the patch harness. So basically a 4 wire run to the sub. I wanted the sub setup to be easily removed . Used a 4 pole Speakon pro audio connector. For the internal sub wire i just used 2 runs of 2.5mm2 cable left over from the install. Overkill at 60amps but no cable loss will occur.

[NealfromNZ]

The Morel underseat woofers arrived today. I’ve installed one at this stage so I can compare to HK. Did a quick volume check with a microphone to see if I needed to change amp channel gain but was within a db of the HK . Interesting as Morel is a 2 ohm and HK is 8. I thought I would needed to add a couple of db to the morel.

Morel have fitted a bigger cone than in the HK. Looks to be about 1 cm wider and deeper. The front motor is attached to the metal frame and the cone as well. The spider is supported by a ridged plastic back. Far stronger and sturdy than the HK. The woofer also has more depth. Power wise it’s rated at 180 rms / 500 peak ( short term ) and has a two ohm load. This will take advantage of the Mobridge amp woofer channels.

I turned off the trunk sub so I could focus on the bass of the two. Change the crossover to 30-150 on both. Morel straight away went deeper than the Hk. Sounding like more volume in the 40hz range.
Did a couple of quick rta sweeps between the two. Confirmed what I was hearing.
Have set the two to run 40-150 hz with 24 db bandpass filter.

Will give the morel some time to run in before more detailed measurements. But it’s off to an excellent start and sounding really good on “Ray Brown” 😀

[Andrew_za]

Those look rather pretty! Thanks to your recommendation im going to try get the ESB's from ahifi. Do you have the RTA from the Morel's vs HK?

[Motown65]

those morels look really nice and i didnt even know they made them. Why are you trying to run the midbass so low though? i have mine at 80hz all 24db lr filters too. Im stock hk l7 with a helix v twelve in between the hk amp and the speakers. Then a jl xd600/1 and 10w6v3 for low end. I did this to keep logic 7 for a two seat tune. Also what sort of signal are you sending the rear speakers?

[NealfromNZ]

Originally Posted by Andrew_za

Those look rather pretty! Thanks to your recommendation im going to try get the ESB's from ahifi. Do you have the RTA from the Morel's vs HK?

I did a quick RTA but will do a more detail one. The morel has only had about 90 minutes of use at this stage. Really needs a bit more time to ensure they are freed up.
Was certainly more output in the 30 -50hz region than HK and acoustic bass is better defined.

Originally Posted by Motown65

those morels look really nice and i didnt even know they made them. Why are you trying to run the midbass so low though? i have mine at 80hz all 24db lr filters too. Im stock hk l7 with a helix v twelve in between the hk amp and the speakers. Then a jl xd600/1 and 10w6v3 for low end. I did this to keep logic 7 for a two seat tune. Also what sort of signal are you sending the rear speakers?

Thanks for your comments. Context is I’m to get more up front bass and detail without going to a front footwell sub. Over the last 30 years I’ve run trunk subs , IB , ported , sealed , with AP Matt’s and last couple have had passive radiators. Im finding that the F80 doesn’t work as well for the subwoofer as the E46 ski pass setup I ran before which had the sub firing directly in cabin. Now it’s more transfer function from the trunk sub s.

Hence experimenting with have the Underseat running down to 50hz to get a good upfront kick and finding a solution that will do this. The HKs weren’t able to get down low enough. Previous subs had been running between 80 and even up to 110 in when used with a 5 1/4 inch two way set.

My F80 had UK spec had base audio so only door speakers and Underseat woofer. But this suits me as the all upper mid bass drivers are on the same plan rather than being 90 degrees out of phase when running rear deck speakers. The door speakers also don’t collapse the front image as much as a rear deck where you typically roll them off before hitting higher frequencies. It also means cost wise I don’t need to replace seven midbass and tweeters. But I did elect to run the same front and rear door speakers to keep timbre matched for when I have two other passengers.

Audio path is a pure digital chain to the amp / dsp so DDA rather than DDAA (HK) with diasychained subwoofer amp.
Front doors are two way active , rear doors are 2 way passive and normally faded right down.

It’s been a while since I’ve heard a logic 7 setup ( mates x6m ) but when we ran through it in our consensus was for music it was better running stereo with centre disconnect. This was us trying to get the sound closer imaging wise his SQ comp car had which did quite well. I did like logic7 however for “live” recorded music.