[Hansie]

Hi
Just bought myself a finest F31 : the Alpina B3.
From factory it had the HK option but thatÂ’s replaced with a aftermarket set up by a previous owner.
As far I can tell now :
Helix V eight
Gladen 600c1
Blam front door speakers
Blam rear door speakers
Underseat woofer, not checked yet
Otherwise stock.

Subwoofer box is removed by previous owner , it was too large, so the Gladen amp isnt connected to any speaker but connected to the V eight.

Only 6 channels of the 8 are used from the Helix :
Front door left and right
Rear door left and right
Under seat woofer left and right

I expected some great music but was very disappointed.
No staging, bass is very booming and no kick bass.
Highs where a bit harsh.

Downloaded the dsp software and checked settings:
Cross over for the underseat was 60 Hz highpass and 80Hz lowpass .
The 10 cm mids got 85Hz low pass.
Changed this to a gambled 130Hz setting improved things a lot but needs fine tuning.

Ordered a Basser box and making my shopping list for some additional speakers.
Subwoofer would be a JL audio 10w1v3-2 , suits the box and amp well.
And thinking to implement a centre speaker.

No clue why the centre speaker and rears are on the stock HK amp ?

How much work is het to connect the centre speaker to the V eight? Anybody has a how to?

Do I need to upgrade the centre speaker too? Still the stock HK set is in there.
IÂ’m not familiar with the Blam brand.

Thank you for any feed back.

[Hansie]

Reply to my own post :
Rear door speakers ain’t working , dsp setting are okay so prob a loose wire.
Ordered an Eton centre and jl audio sub.
When they are in I,m gonna check and connect it all.
As I don’t use the HK amp anymore, think I,m gonna remove it or does it have any other function?

[Encanto]

I would suggest removing the OEM amp completely and replacing it with the Helix SDMI25 MOST converter, then go Toslink to V-Eight.

Wire front/center/woofers and rears (in parallel, 7ch) to V-Eight 8ch, then tune. It should sound much cleaner, tighter, and louder than OEM.

[Hansie]

Thank you Encanto, that's a solid but also quite an expensive solution.
They are 500 Euro and I'm not sure it will be audible, any experiences here?

High level input via de stock amp versus the digital input of the Helix SDMI25.

[Hansie]

Disappointing update :
Both amps are loose in the smaller storage cabin , failure waiting to happen!
For sure in time cables will get loose and components fail, maybe even a fire on a bad day.

So a complete rebuild is waiting for me.
Previous owner told me a professional company did this

[Hansie]

X

[Hansie]

Speakers are BLAM audio and a quite new brand.
No clue if they are any better than HK , bought the car with them and never listened to the HK.
Components look wel made and sound great but probably the helix dsp helps a lot too.
They are rated 3 ohms so not a great replacement without a strong amp.

[Billfitz]

The specs aren't much different than stock, so the results won't be much different either. If anything the door speakers would not be as loud as stock, because their motor strength is less.

[Hansie]

Haha, so it’s a not so good copy of the original!
Not Chinese ,French copy this time.
Still sounds decent to me.
Installed a 10 inch JL sub , amp was there already so very easy.
Known Bassler solution for a F31.
Crossover to the under seats at 80 Hz for now.
Do have 2 types of minidsp mics and REW so gonna measure and see what’s possible when outside temps go a bit upwards.
Still in doubt regarding the helix sdmi25, not sure it will improve things.
Definitely a nice to have, 500 euros is just to much for an impulse buy after a few beers.

[Billfitz]

Crossing to the under seats at 80Hz is a bit high. You shouldn't run them higher than 120Hz, so you're not even getting a full octave from them. I'd try 60Hz.

[Hansie]

Thank you for the free advice!
Under seat is now 80 till 130 Hz , gonna try to 60 till 120 Hz.
Aimed a bit high with 130Hz to protect the mids, although I'm not playing that loud.
Using the Butterworth in 24dB slope, okay I guess?

[Billfitz]

The mids should be fine at 120Hz, especially with 4th order filtering. Running the under seats to 130Hz could make them directionally locatable. They definitely would be if they weren't located under the seats. Since you have the ability to change the pass bands by all means experiment to find what works best.