I recently added 2 JL 8w3v2's, and an Alpine 605 amp to my hk system. With this, I was looking to add a deeper bass signal to the existing system. After having all this stuff installed, I'm a little disappointed in the way it sounds. Its not giving me the "tight" clean bass I was hoping for. Initially I thought it might have been the equipment. But after reading a few posts, it sounds like the dsp part of the HK system might be messing up the signal to my subs. Another words, the sub isn't getting a clean signal from the HU, rather its getting the (DS)Processed signal from the amp- since the sub is tapped into the rear speakers via a high-low converter. Can anyone comment on this? I've tuned the amp as much as possible- slope, freq, etc, as well as tested out the different DSP settings on the HU....but its just not producing the clean bass sound I'm looking for. The sound isn't distorted at all...but for the equipment (which wasn't cheap), I was expecting a little more "punch" and "tightness" in the bass. I was wondering if a passive EQ (Kenwood KGC-9044) or crossover, would remedy this . That way it would allow me to adjust the freqency of the sub somehow. Also, adding this, would allow me to get my signals from the EQ (since there are sub pre-outs) or crossover instead of getting the signal from the rear speakers. Is it even possible to add an electronic EQ or crossover to the HK system? I've never added either of these before, therefore have no idea how it would impact my system. Anyone here an audio buff that can give a little advise on this? I would greatly appreciate it. I've spent the last few days pretty bummed out cuz I spent a good chunk of change to get some subs added and its not quite the sound I was looking for. Thanks in advance for any help!

 

I'm going back a few years here but...

If I recall, BMW uses something called Differential Balanced Signaling for their audio system signals between the HU and the amp. Basically, each channel's audio is simultaneously sent as both positive and negative frequencies. The BMW amp merges only the "mirrored" signals and passes that signalling on to the rest of the circuitry in the amp; any unmirrored signaling (unwanted "noise" picked up from the car's other systems and, thus, NOT mirrored) is excluded. This technique produces a very clean and accurate signal and does a bang-up job of eliminating noise.

However, an aftermarket amplifier that is used with a DBS HU must be capable of deciphering this DBS signaling. If not, the clarity and quality of the recieved signal may be compromised.

Now, while this is true of the BMW audio systems in the E46 3-Series (including the E46 3-Series HK units), I cannot confirm that the HK system in the MINI uses DBS. It does, however, seem likely that this would be the case.

Does the Alpine 605 amplifier support DBS inputs? If so, did you connect the HU to them? If not, can you swap-in a borrowed amplifier that supports DBS to see if that is the problem?

FWIW,

Theo

P.S. You could always replace the MINI HU with an aftermarket HU that does not utilize DBS. So, in the worst case, you may want to compare the cost of upgrading to a DBS-capable amplifier against the cost of a new HU.

 

hey koopah,

thanks for your reply. My knowlege on car audio is very limited....How can i tell if my amp accepts DBS inputs? I see no other inputs besides RCA's....so my guess is no?
I've thought about scraping my entire HK system, but I religiously use the AUX input mode for my ipod and just recently purchased the OEM sirius reciever. So i'd rather not, if at all possible. From reading various posts, it sounds like tuning the HK system is pretty difficult.

 

You probably want to chat with Ian over at gbmini.net - he's posted several blog articles about upgrades to the MINI HK system. I've seen a couple other blogs / web sites that go into gory detail about how the HK system is set up, IMHO it's not very straight forward to "upgrade" it.

 

Here is an excerpt from a post on www.e46fanatics.com regarding the differential balanced signaling issue and an adapter that can be purchased to convert DBS to standard RCA input signals for $50:

Go HERE to a site that sells the VEN4 converter. I would also give them a call just to be sure that you order the right cables for the MINI.

Go HERE to read a most informative thread about improving the sound of an HK audio system in the E46. You might need to join to read the article, but it's well worth it!

Theo

 

thanks for all the replies and informative links. Most of the posts I've read looks very challenging, and I'm not sure if I'm up to opening these cans of worms. How would a crossover or EQ help out the HK system....or rather, would a crossover or EQ clean up the signals to the subs producing a "better" sound? Has anyone done this? Again, my knowlege of the ins and outs of car audio systems is very limited, so I'm looking for solutions that require minimal modification to the exisiting system. Thanks!