There has been another burst of discussion in the various forums recently about the Harmon/Harman(!) Kardon upgrade to the MINI. My MINI is unusual (but no longer unique since I made some HKenabler circuits for MikeyTheMINI in England) – I have upgraded the head unit but still have the HK amp and speakers.
The HK upgrade offers a number of benefits over the stock MINI sound system. There is more power and better speakers, and also various “modes” (MINI H/K, SPATIAL, ELECTRONIC, FESTIVAL, INSTRUMENTAL) that electronically process the sound and “customize” it to the MINI interior. I have found the system to have incredible clarity – cleaner than aftermarket systems I have heard.
The HK system has *eight* speakers, two more than the stock setup, but there are still only the six installed positions – in the top position in each door there is a tiny tweeter positioned in front of a midrange speaker. Additionally, the rear 6×9 speakers have “dual voice coils” which allows twice the power delivery from the HK amp, without the need for voltage boosting. Here’s a pile of pictures:
(UPDATE: the MINI convertible has different rear speakers)
People regularly ask what is the best set-up for the HK system – the answer of course is whatever you prefer! But this famous online discussion can be of some help in figuring out what to adjust and why. There is also a detailed review on MINI2.
Of special note is the fact that if you turn bass or treble above the flat/center setting, you will limit the maximum available volume – the HK system is configured to protect its speakers at the expense of lower overall volume!
Another interesting Harmon Kardon discussion is here, by tacotim who appears to work with developing car audio systems so has opinions worth noting!
There is a regular issue discussed with the Harmon Kardon system – a buzz or vibration from the passenger side of the car. My MINI had this issue and I attacked both doors with sticky felt to solve it. Now a MINI friend, Josh, has done the same thing and posted a how-to on his website. Another how-to is posted on the NAM forum.
This vibration appears to be a common HK issue and is easy to resolve if you are brave enough to remove the door panels (you could also try to get your MINI dealership to resolve it).
Another regular issue discussed is the speed compensation. Non-HK MINIs have a “SPEEDVOL” setting in the head unit menus which can adjust the amount of speed-related volume increase. The Harmon Kardon system does have speed compensation but it is a fixed algorithm in the amp and is not adjustable. It appears to compensate just enough so that with the windows closed, there is no need to turn up the volume at highway speeds but you don’t notice the compensation either!
So some people claim that there is no compensation (from my experiments with different stereo setups, I know that the HK amp does compensate for speed). Another confusion is that the stereo manuals still describe the “SPEEDVOL” adjustment although it is disabled in HK equipped MINIs (except, confusingly, a few early MINIs still had the adjustment in the menus but it had no effect!)
The speed compensation does not take account of interior noise levels (rumours of a noise-pickup microphone are wrong) so the speed compensation will not be effective when the windows are open …
It took me a long time to enjoy the Harmon Kardon system – my preference is for sound to come from in front and behind me, so the default “MINI H/K” mode (which is front sound-staged) did not suit me. I normally use the SPATIAL or FESTIVAL modes now (although FESTIVAL makes speaking voices very echo-ey).
My aftermarket head unit appears to sound better than the original stock unit – probably due to the better “loudness” compensation. But if you are seriously into car audio systems you probably should get the base stereo and replace all of it – amp, speakers, head unit, being sure to use a very competent stereo install company (not Tweeter!)
The best advice is always – listen to the MINI stereo before you order your car. Take some of your favourite CDs and play them. Is the sound clear and crisp? Is there enough volume? Too much or not enough bass or treble?
The very best MINI stereo I have ever heard is an aftermarket system in Jaysons car – but the cost of that system is much more than the HK upgrade, and it significantly impacts space in the trunk.
M&I / GBMINI 