Navigation & Audio Audio upgrades, bluetooth, and navigation discussions surrounding the Clubman (R55), Cooper and Cooper S (R56), and Cabrio (R57) MINIs.

Navigation & Audio Add a subwoofer to Hi-Fi

Thread Tools
 
Search this Thread
 
Old Sep 4, 2007 | 11:06 AM
  #1  
kookmyers's Avatar
kookmyers
Thread Starter
|
4th Gear
iTrader: (1)
Joined: Oct 2006
Posts: 312
Likes: 0
From: San Diego, CA
Add a subwoofer to Hi-Fi

I was just considering my choices for what i am going to do with the audio system in the MINI. I have just purchased some Focal speakers for the front and am planning on installing them with power from the HiFi amp. Hopefully this will satisfy my needs. I would like to add a subwoofer to the system and not lose any of the 10ch from the HiFi. is this possible? i have to get my input signal from somewhere but i do not want to lose the front or the rear.

Unless someone comes up with something, i guess i will tap into the front channel, buy a 4ch amp and use 2 for the fronts, and bridge the rear for the sub, keeping the HiFi intact for the rear 6x9. (i would disconnect the rear tweeters from the output of the amp.)
Bummer. i was hoping to use as much of the HiFi as possible to 'justify' the $550 already spent/wasted.
 
Reply
Old Sep 4, 2007 | 02:31 PM
  #2  
tbonecopper's Avatar
tbonecopper
2nd Gear
Joined: Jun 2006
Posts: 137
Likes: 0
From: Jacksonville, FL
IMO I'm not a fan of heavy bass... I just want to swap my tweeters...everything else sounds ok to mediocre, to me, depending on what I'm listening to
 
Reply
Old Sep 4, 2007 | 04:42 PM
  #3  
SDMike's Avatar
SDMike
5th Gear
Joined: Jun 2006
Posts: 758
Likes: 0
You can always get a line level converter tap into the leads to any of the speakers and it converts signal to RCA low level inputs... feed this to your amp for a subwoofer and you are done. They only cost about 20.00
 
Reply
Old Aug 2, 2008 | 05:30 PM
  #4  
greystone's Avatar
greystone
3rd Gear
15 Year Member
Liked
Loved
Community Favorite
Joined: Apr 2007
Posts: 251
Likes: 18
From: Central CT
You don't lose channels by adding a sub and amp, the high level input comes from a speaker wire, which you splice into. So the speaker wire is still providing signal to the speaker and your new sub amp.

You only need to buy a LOC if you already have an amp and it doesn't have high level inputs.
 
Reply
Old Aug 2, 2008 | 06:26 PM
  #5  
Robin Casady's Avatar
Robin Casady
6th Gear
Joined: Mar 2007
Posts: 7,578
Likes: 4
From: Paradise
Originally Posted by SDMike
You can always get a line level converter tap into the leads to any of the speakers and it converts signal to RCA low level inputs... feed this to your amp for a subwoofer and you are done. They only cost about 20.00
How do you get around the bass cut off in the rear speaker leads? Isn't that filtering done in the head unit or the HIFI amp?
 
Reply
Old Aug 4, 2008 | 02:36 PM
  #6  
D Unit's Avatar
D Unit
4th Gear
iTrader: (3)
Joined: Aug 2007
Posts: 361
Likes: 1
Originally Posted by Robin Casady
How do you get around the bass cut off in the rear speaker leads? Isn't that filtering done in the head unit or the HIFI amp?
I also wonder the same thing. After reading up a bit, this diagram helps me, but I am still a little confused. From my understanding, this LOC (bottom diagram) requires that you feed it the 3 way components full range. So if I fed it with the tweets as high output, mids as mid output, and 6.5" woofers as low output, it will then "internally sum the output" and give my amps the full range, and from there, use my amp's internal crossovers. But where will it sum up the range from 60Hz down where a subwoofer usually goes?

https://resources.myeporia.com/Compa...OEM_System.pdf
 
Reply
Old Aug 12, 2008 | 11:25 AM
  #7  
DanQ's Avatar
DanQ
2nd Gear
Joined: May 2008
Posts: 93
Likes: 1
From: Lake Zurich, IL
Originally Posted by Robin Casady
How do you get around the bass cut off in the rear speaker leads? Isn't that filtering done in the head unit or the HIFI amp?
Is the bass cutoff in the rear a problem on BOTH the HIFI and Non-HIFI headunits? The test data I saw seemed to say it was known on the Non-HIFI head unit, but I've not seen test data for the HIFI headunit...

NON-HIFI test results:
https://www.northamericanmotoring.co...d.php?t=120789
https://www.northamericanmotoring.co...d.php?t=150567
 
Reply
Old Aug 12, 2008 | 12:08 PM
  #8  
Robin Casady's Avatar
Robin Casady
6th Gear
Joined: Mar 2007
Posts: 7,578
Likes: 4
From: Paradise
I believe it is the same with the HIFI. I don't have the instruments to test it, but at the suggestion of a Crutchfield tech I attached one of my NHT home stereo speakers to the 6x9 leads. It produced no bass in tracks that I know had good bass (kettle drums).
 
Reply
Old Aug 12, 2008 | 12:14 PM
  #9  
SDMike's Avatar
SDMike
5th Gear
Joined: Jun 2006
Posts: 758
Likes: 0
I'll double check what wires I tapped into on my lunch break. I believe I tapped the wires coming from the head-unit into the stock amp and that pair allows full signal feed to my amp.
 
Reply
Old Aug 12, 2008 | 12:34 PM
  #10  
dwf137's Avatar
dwf137
5th Gear
iTrader: (2)
Joined: Apr 2008
Posts: 873
Likes: 1
From: Seattle
everyone is saying how the rear 6x9's have the bass cut. anyone tried running a full frequency line to them? Honestly, a good set of 6x9's will out power an 8-10" sub any day.

I'm considering getting an amp for the rear speakers, tapping off of the front speakers, and getting an insane set of 6x9's.... lets hope for no rattles!
 
Reply
Old Aug 12, 2008 | 12:43 PM
  #11  
D Unit's Avatar
D Unit
4th Gear
iTrader: (3)
Joined: Aug 2007
Posts: 361
Likes: 1
Originally Posted by dwf137
everyone is saying how the rear 6x9's have the bass cut. anyone tried running a full frequency line to them? Honestly, a good set of 6x9's will out power an 8-10" sub any day.

I'm considering getting an amp for the rear speakers, tapping off of the front speakers, and getting an insane set of 6x9's.... lets hope for no rattles!
I'm not trying to argue with you, but there's no way a 6x9 can compete with a 10" or even an 8" subwoofer as far as bass goes. In regards to proper SQ (especially imaging), everyone will be better off completely cutting off their 6x9s and adding a subwoofer. If you don't want to add a sub, then get a 6x9 subwoofer like the one made by CDT and NOT a full range 6x9 that will ruin the SQ.
 
Reply
Old Aug 12, 2008 | 05:34 PM
  #12  
dwf137's Avatar
dwf137
5th Gear
iTrader: (2)
Joined: Apr 2008
Posts: 873
Likes: 1
From: Seattle
Originally Posted by D Unit
I'm not trying to argue with you, but there's no way a 6x9 can compete with a 10" or even an 8" subwoofer as far as bass goes. In regards to proper SQ (especially imaging), everyone will be better off completely cutting off their 6x9s and adding a subwoofer. If you don't want to add a sub, then get a 6x9 subwoofer like the one made by CDT and NOT a full range 6x9 that will ruin the SQ.
Not a fan of CDT. I will probably be looking at rainbow or mbquarts, but they won't serve as my only bass, just mid bass. I'm currently getting ready to order the 10" RE SL.

Everyone on here complains that the stock system has no bass, which it doesn't. I think everyone would be surprised that if you put full frequency to the 6x9's and replaced them with something decent, they wouldn't need to put a sub in. There might be something un-foreseen though, like crazy rattles, that's why I asked.

Not everyone is an audiophile. Recommending a top of the line system to the average person is just a waste of your time, and/or their money. I used to run a car stereo business, it's important to realize not everyone wants their sound perfect.
 
Reply
Old Aug 12, 2008 | 09:34 PM
  #13  
k6rtm's Avatar
k6rtm
4th Gear
Joined: Feb 2008
Posts: 447
Likes: 1
From: Silicon Valley
My project for the weekend is to try swapping drive signals to the front and rear speakers, expecting (hoping) that the 6x9s (polk db 691) will be able to do a lot more bass than the combo of the 6.5 (poke db651s) and the 4 inch speakers can do. Additionally, I'd expect the front pair to do better as they aren't seeing all the low end signal they can't reproduce.

This is in the non-hifi system, but if this trick works, it's worth repeating in a hifi system -- and probably a lot easier, just swapping pins at the hifi amp.

Anyone game to try this on a hifi system?
 
Reply
Old Aug 12, 2008 | 09:37 PM
  #14  
dwf137's Avatar
dwf137
5th Gear
iTrader: (2)
Joined: Apr 2008
Posts: 873
Likes: 1
From: Seattle
^i'll give it a shot, however I haven't replaced speakers yet. The rear 6x9's should definitely give a lot more bass then the fronts... In my last car, I had a filter cutting all bass off of my front speakers and man did that sound awesome.

let me know your results... if it works, I'll give it a go on my car.
anyone have a wiring diagram, so I know what pins are for what speakers?
 
Reply
Old Aug 13, 2008 | 09:04 AM
  #15  
k6rtm's Avatar
k6rtm
4th Gear
Joined: Feb 2008
Posts: 447
Likes: 1
From: Silicon Valley
Wiring diagram:

Once again, the WDS site is your friend:

http://www.mcaw.info/wds/mini/us/r56/index.htm

(it wants IE under Windows with the Adobe SVG plugin loaded)

Enter "A18" into the Search box lower left of the window. This takes you to the info on the amplifier -- where it's located, how it's wired.

Short summary from the diagrams:

The outputs run from the radio (X13812) to our favourite connector (X9331). From there, a cable takes them to the amplifier (A18, X10266).

The amp outputs run to the speakers, through the X256 and X257 connectors at the doors, and possibly directly (unclear from diagram) to the rear speakers.

Caveat:

The descriptive text about the HiFi amplifier says "HiFi amplifiers are amplifiers with active frequency gates. Active frequency gates achieve better acoustic results than passive frequency gates. The HiFi amplifier does not have speed-dependent volume adjustment or speed-dependent equalizing. The function of the HiFi amplifier is only to amplify the low-frequency output."

Interpretation:

This is one of those places where I almost wish I could see the original German and have a colleague who is well versed in TechnicalGerman translate. I strongly suspect he'd translate "active frequency gates" as "active filters."

From the diagrams, it looks like they use the same radio heads (nav or non-nav) in both Boost and HiFi systems, and the same basic wiring.

In the Boost system, outputs from the head go to the X9331 connector, and from there to the speakers.

In the HiFi system, outputs from the head go to the X9331 connector (same place), from there to the A18 amplifier, and from there (X10266) to the speakers (X256, X257).

Suggestion:

Try swapping the signal lines on the radio side of the X9331 connector, which is the same thing I'm going to attempt in the non-HiFi system.
 

Last edited by k6rtm; Aug 13, 2008 at 09:05 AM. Reason: the voices told me to fix my typos
Reply
Old Aug 13, 2008 | 10:28 AM
  #16  
rkw's Avatar
rkw
OVERDRIVE
Joined: May 2005
Posts: 8,233
Likes: 127
From: San Francisco
Originally Posted by k6rtm
The descriptive text about the HiFi amplifier says "HiFi amplifiers are amplifiers with active frequency gates. Active frequency gates achieve better acoustic results than passive frequency gates. The HiFi amplifier does not have speed-dependent volume adjustment or speed-dependent equalizing. The function of the HiFi amplifier is only to amplify the low-frequency output."
My interpretation is that the amplifier has active crossovers, as did the 1st gen Harmon Kardon system. In other words, eliminating passive crossovers at the speakers. The HK system also had a DSP that applied frequency equalization and imaging/delay effects. BTW, the HiFi system sourced from Harmon International as well.
 
Reply
Old Aug 13, 2008 | 10:54 AM
  #17  
mslatter's Avatar
mslatter
4th Gear
15 Year Member
Liked
Loved
Joined: Jun 2008
Posts: 532
Likes: 28
Originally Posted by k6rtm
Wiring diagram:

The function of the HiFi amplifier is only to amplify the low-frequency output."
To me, the interesting part of that sentence was "low-frequency output." Are they implying that the amp has a low-pass filter prior to the amplification stage, so that it might, indeed, be amplifying the lower frequency relative to the rest of the curve?

That doesn't make sense to me - roll off the bass aggressively in the head unit, then amplify it after the signal leaves the head? My suspicion is that the amp amplifies all frequencies evenly, and that that phrase in the documentation is incorrect.

Then again, I'm just biding my time by talking until someone more qualified than I can do actual physical measurements.
 
Reply
Old Aug 13, 2008 | 12:18 PM
  #18  
Minidrivr's Avatar
Minidrivr
6th Gear
Joined: Jul 2007
Posts: 2,881
Likes: 6
Originally Posted by k6rtm
Wiring diagram:

Once again, the WDS site is your friend:

http://www.mcaw.info/wds/mini/us/r56/index.htm
If you navigate back a little bit you can download a compressed file that has that entire site on it. To use without a net connection.
 
Reply
Old Aug 13, 2008 | 12:42 PM
  #19  
k6rtm's Avatar
k6rtm
4th Gear
Joined: Feb 2008
Posts: 447
Likes: 1
From: Silicon Valley
I'm looking, but I'm not finding... Hints, please?

--bob
 
Reply
Old Aug 13, 2008 | 08:38 PM
  #20  
dwf137's Avatar
dwf137
5th Gear
iTrader: (2)
Joined: Apr 2008
Posts: 873
Likes: 1
From: Seattle
k6rtm... let me know how your test goes... since the hi-fi system uses the same headunit, it shouldn't make a difference. The amp might be doing even more horrible things. Where, physically, is the X9331 connector located?
 
Reply
Old Aug 13, 2008 | 09:38 PM
  #21  
k6rtm's Avatar
k6rtm
4th Gear
Joined: Feb 2008
Posts: 447
Likes: 1
From: Silicon Valley
According to the pictures, the X9331 connector is located just ahead of the driver's door, underneath the bonnet latch. The WDS site gives you pictures and much more.
 
Reply
Old Aug 13, 2008 | 10:56 PM
  #22  
dwf137's Avatar
dwf137
5th Gear
iTrader: (2)
Joined: Apr 2008
Posts: 873
Likes: 1
From: Seattle
hmm.. i guess I haven't dabbled enough in the wds site.
 
Reply
Old Feb 16, 2009 | 09:15 PM
  #23  
pepegrande008's Avatar
pepegrande008
3rd Gear
Joined: Nov 2007
Posts: 297
Likes: 0
Ok so does the bass cutoff problem occur on 02 r53s? im in the process of installing a 10" in the boot and i am tryin to figure out the best way to wire in the rca's. my car has the non hk audio but i did swap the deck out for an 03 deck in order to have an input to the rear. Any words of wisdom. Also does the x9331 adapter exists on the r53? i took a peak and its not where it looks like it should be on my car.
 
Reply
Old Feb 17, 2009 | 07:34 AM
  #24  
crpagan's Avatar
crpagan
2nd Gear
Joined: Mar 2007
Posts: 114
Likes: 0
From: Melbourne,FL
I am about to install a Power Acoustik [FONT=Tahoma][SIZE=1]AWB-10 800 Watts MAX active woofer box with built in amplifier and i have hifi stock system. Where do i get the signal for the high low converter to get rca's for the amp? Do i have to tap into the front door speakers? I don't know if tapping into the rears since everyone is saying the rears don't have a low signal. [/SIZE][/FONT]
 
Reply
Old Feb 17, 2009 | 10:02 AM
  #25  
crpagan's Avatar
crpagan
2nd Gear
Joined: Mar 2007
Posts: 114
Likes: 0
From: Melbourne,FL
Also has anyone on a hifi system tried to swap the wires from the amp to the fronts to the rears so that the rears have more low end since they are bigger? Can it be done?
 
Reply



All times are GMT -7. The time now is 08:35 PM.