I have a standard Boost non Hi-Fi audio system with Bluetooth upgrade in an 08 R55 Clubman.

Having read about the 100Hz cutoff I decided to code out the setting the in the RAD2 settings module.

I can't hear any difference and I'm wondering if the cuttoff only applied to the hatchbacks. The Clubman body is acoustically very different to the hatchbacks and I'm wondering if there are some differences in the radio and speakers between the R55 and the R56. Although I have coded out the cutoff it would have a similar effect to swapping the front and back speaker outputs, I would think.

Can anyone confirm this?

Also in the RAD2 module there are many other audio settings that are set specific to the R55. They appear to be volume levels but cold mean other things.

Also I didn't think that the Boost system was too bad (before the change). I previously had a BMW E91 with professional radio which appears to be the same as the Boost. The audio low frequency quality was slightly better in the E91 but I would expect that in a bigger car with bigger door chambers and better insulation. I think I would hear a 100Hz cuttoff as I used to have an Alpine head unit (in another car) that allowed you to set the low frequency cuttoff. I remember that setting it to 80Hz was about right whereas 100Hz started to kill it. All very vehicle and speaker, etc dependent, but there was a noticeable effect that I don't hear in my R55 having made the change.

 

Do you have stock speakers? If so, they can't reproduce very low frequencies which might explain why you can't hear a difference.

 

Yes speakers are stock. I understood the mod was for standard Boost system cars with standard speakers. Perhaps I have understood this and that you need better speakers as you say to hear the difference.

 

I had another look at this today and read the ECU module for the audio system.

Guess what? I didn't notice it before but there is already an entry for the R55 and it was set to HiFi.

There are the entries which in their default state are:
pl2_hifi
r55_hifi
r56_stereo
r60_hifi
r57_hifi

That would explain why trying to remove the 100Hz cutoff made no difference because the Clubman does not have the 100Hz cutoff like the hatchback. Unless of course someone had already made the change in my car - unlikely.

Can anyone else confirm there is no 100hz cutoff in the r55 Clubman?

 

Our 2010 R55 clubman with the base stereo had the 100Hz cutoff. I was able to change to hifi settings using ncsexpert & ncs dummy.

(I know it's an old thread, but someone might find the info useful)

 

Some claims that R53 non-HK also cuts off at 100Hz in the rear. I totally disagree because I wired the rear channel of my OEM CD Receiver NonHK to an Alpine KTP445U amp and use the Alpine's output as source to an amped 8" sub (MTX) and the bass is just amazingly punchy and definitely well below 100Hz.
It's the OEM rear speakers and the OEM strereo's rear power output that sucks. I suggest to do more research for the R56..

 

I did the front-to-rear, rear-to-front channel switch in my 2013 Clubman ("Boost" system), and it made a BIG difference. Now the 100Hz cutoff affects the signal to the smaller front speakers - instead of the bigger speakers in the rear, which are able to make better use of the bass. There is no question about it. The difference in sound is obvious without needing to use any sort of technical equipment to measure it. It sounds MUCH better after the front/rear channel switch.

 

The rear RMS output on the non-HK is very weak. When I took off the OEM rear speakers in my R53, the rating is only 15 watts at 5 Ohms. I don't know if it is the same case as R56 & Clubman.
Back to 100 Hz cut-off rear channels, if this is true as also claimed by few R53 owners, my powered sub could have sounded bad. Here is my set-up:
F & R outputs of OEM nonHK CD Receiver ---> F & R of Alpine KTP445U Amp ---> Front Output of Alpine powers the front & rear speakers that were connected in parallel ----> Rear Output of Alpine goes to the MTX amplified Subwoofer.
Anyways, glad if your f/r swap made a good difference which makes sense bec. R56 and Clubmans front speakers are only 4" and rear speakers are 6x9"