Gentlemen, this thread has shown me just how little I know about stereo systems ( and how lost the local stero shop goons are). Now that we know roughly what the design and operating loads of the stock HK system speakers are:
Do you have any recommendations for replacement (upgrade) speakers to be used with the stock HK amp. Either direct replacement or slightly different configurations, possibly using the Infinity Basslink for a bolt in self amplified sub.

What I really am looking for is:
1. a little more volume (nothing crazy, just a little)
2. crisper high end
3. less muddy bass ( I had hoped by relieving the stock speakers of the responsibility of producing the lowest frequencies, the first two would be somewhat remedied.)

I know it seems that I want the world without changing out much of the stock system. IS IT POSSIBLE?........

 

Did we ever get any specs on the HK radio/amp? that might be good to have in order to match speakers to it.
Of course you can't really tell what would happen unless you actually do it- maybe check with stereo shops that do sound upgrades for coopers- someone with experience. If you can't get the specs then you are just guessing what the output is. If you add an aftermarket amp then at least you can match the speakers to that amp since you know the specs.

 

For anyone that needs info on settings for HK be sure to see
http://users.exis.net/~rcwomack/mini-hk-stereo.html
It's worth a read

 

I seem to remember the Bose system in our Miata having 2ohm speakers too... is it some kind of trick they do in the 'upgraded' factory fit systems..?? The Bose was horrible... all bass even with the control turned way down. It would shake the rear view mirror with the top *down*. May suit some 'tastes' but not what I was looking for in car audio..!

 

I think the sound of each BOSE system is dependent on which car it is installed in. I have a 1995 Nissan Maxima with the BOSE system and it works fine. It isn't quite as good as a high end audiophile system but it isn't bad at all. It was balanced with good clarity, not too much bass at all but you could adjust for more and run lots of power if needed. Cost an extra $700 more than the standard system that was inferior by comparison. :smile:

 

As an acoustics engineer who's been at several successful hi-fi companies, and now the auto industry, I can say that there's more to speakers than looks. Paper is a light-weight, stiff, and well damped material-ideal for a loudspeaker. It's been possible to add treatments to paper to make it unaffected by water/heat/cold/etc. for 20 years. Exotic materials mainly have their place for marketing appeal.

Speakers should be judged by their efficincy, frequency response (bandwidth, flatness and smoothness), distortion (ability to play loud without it). There are likely better speakers to be had, if you choose carefully, so choose carefully. Get data.

Finally, keep in mind that the system (HK) has custom equalization (as well as other vehicle specific customization in DSP). Some changes you make may be fighting this. Be objective about what you're trying to do (less boomy bass is a good goal-you need to know what qualities/parameters of a speaker control this). Less edgy treble is a good goal, you may try some thin felt or cloth behind the grille, instead of an expensive tweeter.

In my work, I don't make a change to a component in a system without understanding that components performance first. Understand what job the parts in the car are doing. You may be affecting more than one variable with a change. (Changing the mid/tweet co-ax may improve treble, but a lone tweeter will have a hard time filling in the midrange without distortion.)

If my employer will allow it, I'll see if I can post measured data on the sytem, along with the results of double-blind jury evals. (when I get my MINI in 2 months)

 

tacotim-
Thanks again for your advice- I'm beginning to understand. Looks can be deceiving- I see. Maybe if it ain't broke don't fix it?
My next cooper will have the HK system and I'll leave it stock- Now I just have to convince someone in my family that they need to buy a cooper.
I wonder- could I not just buy the whole HK system from someone and put it in my old cooper S, then they can move up to an audiophile system of their choice?

 

---> tacotim, care to disclose your secret past? You have my attention!
Where did you go to school, I went to UM in their Audio Engineering program, but spent most of my time doing my own research (which proved to be quite productive).

Cheers,
Ryan

 

>>I wonder- could I not just buy the whole HK system from someone and put it in my old cooper S, then they can move up to an audiophile system of their choice?

I don't think this is a path worth taking ...
You would have to do loads of work to get the HK in - new wiring from amp to speaker positions, assuming that the amp & speakers fit in a non-HK.

I will soon have a removed HK system but I don;t expect anyone to want to buy it. And I will still need something to go back in the car when/if it is sold!

 

iancull-
Thanks for the reality check-
Here's the audio options for mini owners as I see it.

Need vs Solution
1. For basic audio-just running around town-not a great music lover, never owned a great stereo, have some music CDs or mostly listen to radio.
Best to just stick with the stock radio- it works and the sound is good enough for most people. Doesn't cost more $$$

2. For those whe would like a better sound system- with no hassle, something with more power, more base, more controls, looks nicer and don't mind waiting longer to order a mini.
Best to order the HK sound system for $550, it represents an easy factory installed and warranted improved and tested sound system that is engineered for the mini. Most poeple will not need to upgrade it any further.

3. For those who demand the best in audio, always have and willing to spend more to get it. You're going to pull the entire sound system out so probably you should buy the basic system, save the $550 and put it towards the final system. Add something like the infinity BassLink to hold you over for a little while if you need some time before you upgrade everything. This way the BassLink can be either used in the new system or sold to another mini owner.

4. For those like me that bought an older mini before HK was an option or could not wait for HK. You can do a limited speaker upgrade (component speakers in the front tweeter/mid with crossover and 6x9 coaxial rears) and it does sound better. But be careful how much you spend because the improvement is not going to be dramatic, I would say it is a slight improvement. Could be that the stock radio unit/amp is the limiting factor. If you just want more bass and you don't really need more highs or clarity than the stock system then you can just add the Infinity BassLink to the stock system and that works fine also.

Now after all this talk I went back out to my car and turned all of the controls to neutral- treble, bass, fader. Then I tried various CDs and cranked up the volume to the highest non distorted setting. And it was pretty good. Reasonable bass-not excessive, clear (not sparkling highs), pretty balanced sound from the front and rears. Not bad. I think I can live with it until I buy another cooper with HK or better. I'am using the stock radio and only added MB Quarts to the front and rears. My cost- retail prices and professional install- 3 year warranty $600. If you can do it for $350 to 450 then it might be worth it. Have Fun


On 6/13/03 I added an Xtant 4.4 amp (50 watts x 4 channels). Price $550 plus connector, wires, and installation.
The results are dramatic. The MB Quarts provide ample clarity and bass front and rears. Adding a good amp to the stock speakers might also provide an improvement as the speakers are reasonably good.
_________________
ALOHA

 

Minihune's reality check is a good summary. The Harman system at $550 is a great value. We (Audio Systems Engineers-I don't work at Harman, to be clear) really do put a lot into a factory "Audiophile" sound system. The looks of the part, behind the trim, can be deceiving.

As for point 3. If the best in audio is what you're after, there are probably a handful of shops in the country, with the expereince and tools to create a sound system that exceeds the performance of facory "Audiophile" sound system accross the board (in many system attributes). These involve leaving your car for a month and $10,000. Unless you see your autosound installer with measurement equipment and the industry standard six microphone localized sound power array, and the ability to apply 20-40 bands of equalization, de-correlation algorithms, he/she will have a hard time balancing the system for all around great sound quality, in addition to the better bass, treble, and dynamics (that you're likely looking for in an aftermarket install).

 

>>Unless you see your autosound installer with measurement equipment and the industry standard six microphone localized sound power array, and the ability to apply 20-40 bands of equalization, de-correlation algorithms, he/she will have a hard time balancing the system for all around great sound quality, in addition to the better bass, treble, and dynamics (that you're likely looking for in an aftermarket install).


...and none of this DSP is needed if a well-engineered passive-crossover combined with optimized driver parameters can be implimented!

 

That's not true. It's naive to think that speaker performance is the only, or even the biggest contributor, to good sound system performance. There are many aspects of the speaker packaging, and acoustics of a very small space, that affect whatever speaker you use. A single speaker's frequency response, as you hear it in the driver's seat, is impacted by it' location, the grille in front of it, the trim around it, the spacer/watershield used that its mounted to, the pathlength differences between the direct sound and the sound that arrives after reflecting around, the standing wave patterns in the car, to name a few (at a very high level). I have seen excellent speakers ($500 seperates, with crossovers) with excellent specs, and excellent measured performance out of a car, installed in a car, and the frequency response be no better than +/- 10 dB from 100 hz on up (worse below that).

As for crossovers, the ideal crossover point, slopes, and type depend on the application. Speakers farther apart need diferent crossovers, than ones close together. If the woofer is low in the door, you need a different low-pass than if it is high... Often the woofer or tweeter needs gain or attenuation to match overall output level in the car (even when they matched well out of the car, or according to the specs).

Let's say you pick the right crossover, what can you do if the acoustic loading of the trim on the speaker creates a 6 dB peak at 1 kHz. Your crossover is at 3 kHz (typical for a 1" dome), your treble control or bass control don't touch it.

For these reasons, bi or multi-amped systems (gain control for each speaker or speaker set), electronic crossovers, equalization... Are needed to optimize a system for balanced, natural frequency response. DSP is a very efficient, robust, flexible way to do this, making vehicle specific optimization possible.

Further, the acoustics of small spaces greatly impact imaging and ambiance. Imaging, in part because you are closer to one speaker (or set) than the other(s). Attenuating one (something easy to do passively) can help the driver but make it much worse for the passenger. Since the brain creates "image" from loudness and arrival times, it's possible to use DSP to delay some speakers to bring the image into balance for the driver, and not spoil it nearly as much for the passenger. Or you can decorrelate the left and right signals at certain frequencies to make the image better for both passenger and driver, or some combination of each...

Also affecting imaging and ambiance are factors associated with small room acoustics. Standing wave patterns are causing large fluctuations in frequency response right in the "punch" and "voice" regions. Often vehicles have a big peak at 200-300 Hz, followed by a big dip at 400-500 Hz-it would be a huge challenge to find a speaker with exactly the complementary response to a specific vehicles acoustic anomolies.

As a listener, you're in the reverberant field. In other words, the sound that gets to your ears is made up more of stuff that's bounced around than the stuff directly from your speakers. The reverberant time in a car is about 50 ms, and it's reverberation rise time is only 16 ms. This contributes to poor image depth, the inability to pinpoint images, and poor ambiance. This can be miigated somewhat by decorrelating some of the reverberant energy. Unless you're prepared to derive the L-R singal from your radio, filter it, and feed it to a pair of dipole surrounds, you'll be hard pressed to accomplish this without DSP. Consequently, some decorrelation of front channels can also mitigate some of the standing wave and pathlength problems contributing to midrange colorations.

 

Question for tacotim and darksky:

based on the images of the H/K speakers, and the info found in the outside link previously posted by darksky on how the H/K system works (very informative, thanks!) we now know that the rear speakers are DVCs, and that they are driven in very different ways dependent on mode. I wonder whether they are used / driven in the typical manner of DVCs, in fact, I doubt it. I wonder if one coil is consistently used for the (sub) woofer use of the rear speaker, and the 2nd coil is only used in the modes where the rear speakers are driven as broadbands? Any thoughts? This could affect (significantly in fact) how to replace the H/K speakers with others while keeping the head unit and DSP/amp, if it is even possible to replace them without losing a significant amount of the functionality of the H/K DSP unit.

 

When I get my MCS I'll have it in the lab, and plan to address how each coil is driven. Quite often, one coil is driven as a woofer, and the other full-range, in these situations.

 

I don't really have much to add to this thread...
Just in case nobody has done their homework: Infinity, harman/kardon, and JBL are all part of Harman International. The majority of car speakers manufactured by this group are made under the Infinity label with JBL providing subs and amps. As far as I've seen the Mini has the only h/k car speakers... I don't know if this means anything or not, they may or may not be engineering their speaker designs independently.

As a side note to remove the extreme bass from the h/k system, give the Instrumental setting a shot. Electric seems to be tuned much the same with more base kick and I've found Spatial works well for cruising down the interstate with the windows and the sunroof wide open.

 

Sorry to drag this thread up again ...

I had my doors off again today, to run new speaker wires (wow what a tough job!) and I had been asked to take a pic of the grille to see if the speaker "seals" against it.
:smile:


_________________
Ian C. Gloucester, MA
<A href="http://www.gbmini.net">"GBMINI"</a>...uot;</a>

CWFFC member. Indi Blue / Lapis Blue MCS ... body color exterior trim, chrome grille, painted roof Union Jack, Euro shelf and working rear fogs

 

One other thing ...
"GadgetGav" (on MINI2) had my head unit out this weekend to check that his hand made AUX cable works with HK systems (which it does).
We noticed a number of "bodged" wires on the HU connections, as if the vehicle harness was not quite ready for HK systems.
My MINI was a Jan 2003 build, so I wonder if the HK is wired any better now.

In any case, it is all coming out next month ...

 

Information on HK (sorry - very off topic for the MB Quarts, but all my other HK stuff is here so WTH).

Scoped the speaker outputs from the stock HU today.
When the HU is running with the HK amp shut off, the HU behaves as a normal unit varying its output with volume/fade/balance etc. Since the same HU part number is used for HK and non-HK systems, no surprise there.
The HU output peaks at about 10V p-p (no idea how much distortion there is at that level, though).

When the HU is running with the HK DSP amp working, the HU speaker outputs are "locked" at about 3V p-p; volume/fade/balance adjustments have no effect; this is sensible so that the HK amp gets a reasonably clean signal, and does the volume processing internally ... you could almost describe it as "3V preouts" for those that like the flashy stickers on aftermarket equipment :smile: