HK with aftermarket head unit

[Liam"S"]

HI people,
I am looking into changing the head unit in the mini. It is going to have the H/K hifi upgrade.
I have done a search but it turned out inconclusive, now i have seen on some threads that an aftermarket head unit is incompatible wiht the h/k is this true?
If any of you have transfered to a new head unit which one did you go for and did it make any diff?
Liam.

[musicman]

The H/K hifi upgrade is indeed incompatible with an aftermarket headunit.

The only solution that BMW could offer for this problem is to keep the original BOOST headunit (but hidden away in the interior) and connect the I-bus (connector on the back of Boost headunit) with the HK.

The new headunit should then be connected to the inputs of the H/K Amplifier.

If you should keep the Boost headunit in the dashboard and find another space for your new headunit, you could keep the DSP-settings, since these are controlled via the I-bus.

Trouble is, where do you put the aftermarket headunit?

[Liam"S"]

HI thanks for the reply. wow that seems to be a lot of hassle. My next question is can you get an aftermarket set up in the mini that has the same quality as the H/K for the same ammount of money?
Liam

[GBMINI]

I hope to have time before I fully rip out the HK system in my car to connect up a new HU and see what the amp does:
- It might do nothing
- It might work but have limited volume range
- You certainly won't be able to adjust the HK specifics

If I manage to try it, I will let you know the results.

As for aftermarket ...
I claim putting new speakers on the stock HU gives a very good result, provided you don't need loads of volume and/or loads of stomach churning bass. New speakers will run you $200-$500 a pair (you will need to check UK pricing) ... so you could replace fronts & rears for about the cost of the HK.

Beyond that, there is a mod to get line outs from the stock HU, and you could take that to an aftermarket amp and new speakers - but you are now heading for double the price of the HK upgrade.

In any event, if you don't go HK you probably want to go boost instead of wave - from what I read, there is a noticeable improvement (over here, our bass model is the boost).

[musicman]

When you connect an aftermarket headunit to the H/K amplifier it just does nothing.

I don't think you can get the same quality in aftermarket material for the same price.

I personally can live with the H/K system when listening to a CD, but here in Belgium, the radio reception of the BOOST headunit is extremely poor.

The lack of MP3 compatibility also bothers me.

But I think that if you want better quality (amp and speakers and Headunit) than the H/K with Boost set,it will at least cost you trice the amount you paid for the H/K (BOOST is standard equipment in the Belgian MCS)

[GBMINI]

Musicman,
I agree that the HK represents a good price/performance package.

You say that connecting an aftermarket HU to the HK amp does nothing - so you have tried this?
Did you drive the "turn on" signal to the amp as well as the speaker levels?

[musicman]

Until now, there have been four futile attempts to make the Alpine aftermarket headunit work with the H/K amp. Connecting the remote ("turn on signal") for amp has no effects. BMW Belgium explained me that the BOOST headunit gives an electronic code to the H/K amp to make it work. This code cannot be produced be the aftermarket headunit, therefore, the amp stays off-line.

The only solution is to keep the BOOST-head-unit to give the amp the code to start up and feed the sound via the outputs of the aftermarket headunit.

[Crashandburn]

Quote:

Originally posted by musicman
The lack of MP3 compatibility also bothers me.

interesting. I've currently got a Sony CD/MP3 changer in my cooper (TD70MX I think) hooked up to the standard Wave HU via a connects2 adapter (MBMS005). I was thinking of transferring it to my next car, on which I was going to spec the HK upgrade.

Do you think the HK would be incompatible with this?

[GBMINI]

MP3 compatibility being referred to is the inability of the stock HU to play CDRs which have MP3 tracks on them.
If your CD changer can handle them, the HK will play the result with no issue.

[Crashandburn]

it can,



cheers ian.

[sprocket]

It's actually quite easy to replace the H/K headunit.

Replace the headunit and get a new small amp (replacing the H/K amp). Most modern head units have very good built-in DSPs anyway.

[GBMINI]

Sprocket,
Have you done this?
My worry is that there are no crossovers in the HK system (filtering is presumably all done inside the amp) so if you don't change the speakers too, I think you will have trouble.

[GBMINI]

Replaced my stock HU with Kenwood 759 today.


Musicman is correct - the HK amp does not put out any sound unless the stock HU is connected.
So, until I install new amp and speakers, I hooked the old HU up to the B+, B- and Kbus signals so that the HK amp is happy.

The HK amp gets its settings from the old HU (laying in the trunk) and amplifies the sound from the new HU.
Interesting is that the steering volume still works - it seems that it adjusts the volume in the old HU, and the HK amp must get the volume setting (as well as bass, treble and the DSP mode).