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X3 E83 (2004 - 2010)
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  #201  
Old 02-02-2012, 12:06 AM
alexsih alexsih is offline
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Talking

I was trying to see if I can get away with preserving my boot/trunk.
The alternative is to get a custom fabricated fiberglass enclosure that can go in the right hand corner with a 10" sub powered by the mono channel.

What do you think of the following... I can probably wire the mono amp now to the stock "subs" (again in series - I believe that Evlengr asserts that they are not that "bad" - but he didn't say that they were good ) until I can find a custom fabricator to do the sub work. Afterwhich I can redirect the amp to the sub and reconnect the stock subs to the head unit. This way I can save the money for the 8xi and redirect to the custom work

BTW,

I want to know how yours sounded like after you dynamat-ed the enclosures, how did it improve the low end? Did you use the stock drivers or what did you use.

alex

Last edited by alexsih; 02-02-2012 at 12:11 AM.
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  #202  
Old 02-02-2012, 03:22 AM
x3oiler x3oiler is offline
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Quote:
Originally Posted by alexsih View Post
I was trying to see if I can get away with preserving my boot/trunk.
The alternative is to get a custom fabricated fiberglass enclosure that can go in the right hand corner with a 10" sub powered by the mono channel.

What do you think of the following... I can probably wire the mono amp now to the stock "subs" (again in series - I believe that Evlengr asserts that they are not that "bad" - but he didn't say that they were good ) until I can find a custom fabricator to do the sub work. Afterwhich I can redirect the amp to the sub and reconnect the stock subs to the head unit. This way I can save the money for the 8xi and redirect to the custom work

BTW,

I want to know how yours sounded like after you dynamat-ed the enclosures, how did it improve the low end? Did you use the stock drivers or what did you use.

alex
With no matting, ports left as is, SWS-8X installed, then bass is pretty boomy. Much better than it was but not "tight". With ports sealed and enclosures matted, bass is tighter but after listening for while I think can be better - strong but shallow and not rounded out is the best I can describe it. You can certainly get a stomach thump though.

The problem is that with the port sealed the resulting sealed enclosures are no where near the minimum volume required for proper operation of these speakers ie the voice coil is fighting the restricted air volume. You would not be advised to run the SWS at rated power under these conditions - voice coil might be damaged. This is not an issue for me as max power input is 75W in my setup.

I intend to open the ports again, play with the Alpine PXE-650 I now have (very well priced these days btw) but with the PXE set up to only run the bass (to begin with as minimal wiring changes) and see with ports open if the PXE can tame the boominess a bit - just to see what "can" be done with some smart equalisation.

I agree with Deafwish that a separate sub will be better but like you I will go the little extra to retain by trunk space hence my play time.

Also note that Evlengr's comments that the existing speakers sound ok with better driving need to be taken in context - he as 8 inch - I and Deafwish had/have 6 inch and so I would expect a fair difference - but that might be the typical Aussie dumb down by BMW compared to what you get in the USofA.
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  #203  
Old 02-02-2012, 09:42 AM
alexsih alexsih is offline
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I am going to use AudioControl EQX for the equalization. It also has built in crossovers and the amp does so as well. Then use a realtime spectrum analyzer to flatten the curve and hopefully balance out the boominess. I am hoping wiring the SWS or the stock subs in series will limit the current as it will be halved across 2 subs. My main concern is will it be loud enough?

Quote:
Originally Posted by x3oiler View Post
With no matting, ports left as is, SWS-8X installed, then bass is pretty boomy. Much better than it was but not "tight". With ports sealed and enclosures matted, bass is tighter but after listening for while I think can be better - strong but shallow and not rounded out is the best I can describe it. You can certainly get a stomach thump though.

The problem is that with the port sealed the resulting sealed enclosures are no where near the minimum volume required for proper operation of these speakers ie the voice coil is fighting the restricted air volume. You would not be advised to run the SWS at rated power under these conditions - voice coil might be damaged. This is not an issue for me as max power input is 75W in my setup.

I intend to open the ports again, play with the Alpine PXE-650 I now have (very well priced these days btw) but with the PXE set up to only run the bass (to begin with as minimal wiring changes) and see with ports open if the PXE can tame the boominess a bit - just to see what "can" be done with some smart equalisation.

I agree with Deafwish that a separate sub will be better but like you I will go the little extra to retain by trunk space hence my play time.

Also note that Evlengr's comments that the existing speakers sound ok with better driving need to be taken in context - he as 8 inch - I and Deafwish had/have 6 inch and so I would expect a fair difference - but that might be the typical Aussie dumb down by BMW compared to what you get in the USofA.
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  #204  
Old 02-02-2012, 10:19 AM
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gzep23 gzep23 is offline
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whats stage 2 and three????????????????????????????

really wanna replace the subs under the seats...is that the other stage?????
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  #205  
Old 02-02-2012, 10:21 AM
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disregard above post...jsut read first post of this thread sorryyyy!!!!!!!!!!!!!!!!!!
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  #206  
Old 02-02-2012, 02:26 PM
deafwish deafwish is offline
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IMO, you are never going to get proper subwoofer sound out of the underseat enclosures.
I still have them factory wired through my 4" Hertz Splits and I have incredible stereo midbass (my woofers are 6") with the near 100Wrms they are getting.
From my experience, the smaller the enclosure - the higher the power handling (far less chance of bottoming out).
Has anyone modelled an SWS in WINsid/ enclosure building program?
You may find that they need a massive enclosure to get a resonable response out of them!
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  #207  
Old 02-02-2012, 07:46 PM
x3oiler x3oiler is offline
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Quote:
Originally Posted by deafwish View Post
IMO, you are never going to get proper subwoofer sound out of the underseat enclosures.
I do not disagree - but I will trade this off for more interior space - I will try for best I can get then review - possibly with you

The SWS-8/8Xi specs state minimum 0.19Cuft and maximum 0.6Cuft for a sealed enclosure. Example minimum internal dims. 10" x 9" 3-1/2" so can be put in quite a small enclosure - just not quite as small as the under seat cavity - a but more depth would be nice but not possible.
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  #208  
Old 02-02-2012, 08:22 PM
x3oiler x3oiler is offline
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Quote:
Originally Posted by alexsih View Post
My main concern is will it be loud enough?
I have no quantitative answer.

I am running the two SWS from the 2 outputs of the focal solid 2 amp rated at 75watt each into 4 ohm ie running as stereo with 150Hz rolloff. ( so aggregate power into two speakers is 150watt). How much of this I am using? I am running the Focal using speaker level inputs from the head unit with the gain set to approx 25%. Of course this does not mean a lot but I have balanced the focal gain to provide matched audible sound levels with the head unit set at 75% volume running just the front alpine 410's. (note the stock HU is still running my Alpines in the doors but via 300uf coupling capacitors now) This is quite/very loud.
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  #209  
Old 02-02-2012, 08:49 PM
deafwish deafwish is offline
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Quote:
Originally Posted by x3oiler View Post
I do not disagree - but I will trade this off for more interior space - I will try for best I can get then review - possibly with you

The SWS-8/8Xi specs state minimum 0.19Cuft and maximum 0.6Cuft for a sealed enclosure. Example minimum internal dims. 10" x 9" 3-1/2" so can be put in quite a small enclosure - just not quite as small as the under seat cavity - a but more depth would be nice but not possible.
Manufacturer enclosure spec's are often far from reality - when you factor in cabin gain!
IIRC, Boston had their G5's sales brochure stating that it works in a 0.5 cu ft enclosure.
When you modelled it's Thiele & Small parameters into a box building program - it showed that you needed almost a 2.0 cu ft box to get a reasonable response from!
Enclosure sizes are often just used for marketing purposes.
p.s. Speaker manufacturers generally get much fewer warranty claims on subs being in smaller enclosures - due to the damping factor (pressure) being larger in a small box. Some food for thought...
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  #210  
Old 02-04-2012, 01:05 AM
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Evlengr Evlengr is offline
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I just wanted to say I love all the activity this thread is getting. 5 years ago I got my first X3 and brought up changing the sound system. It was almost to the point of getting hate mail for even mentioning such heresy.

Now I see people like you guys taking it to the next level of not just plug and play installs, but some serious tweeking and great advice.

Thanks for your work, advice, spirit of electronic adventure
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  #211  
Old 02-06-2012, 04:15 AM
whiterasta whiterasta is offline
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See my video for a better look at my sub set up.



I added a stealth sub in my trunk on the left side. Takes up no room at all. Custom install and had to pay YES. But love the extra low end and saved space. It's nothing massive. Nice little 10w0 by JL Audio powered by a Rockford under the floor where the battery is.
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  #212  
Old 02-06-2012, 04:23 AM
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Evlengr Evlengr is offline
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Rasta two comments/questions for you:

You should get the silver/black carbon fiber roundels for your X3 like I did. See pic

And the box you had made for sub. Is it a single custom box placed in that panel area, or did he just create a facia the sub mounted to?

I ask as my next question would be: Can he make another? I have a 10" Boston Acoustic low profile dvc and I like the way it sounds, but would love to gain the added space by getting rid of the bass box. It's small, only .74 cu ft, but that would be nice come summer time when beach stuff is always in trunk.

I like your set up. However, I opted for a head rest clip on for our iPad, since it plays movies great and can be removed when going to airport or hotel to keep it safe and in use by wife or little one.
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  #213  
Old 02-06-2012, 04:26 AM
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Evlengr Evlengr is offline
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Quote:
Originally Posted by deafwish View Post
Manufacturer enclosure spec's are often far from reality - when you factor in cabin gain!
IIRC, Boston had their G5's sales brochure stating that it works in a 0.5 cu ft enclosure.
When you modelled it's Thiele & Small parameters into a box building program - it showed that you needed almost a 2.0 cu ft box to get a reasonable response from!
Enclosure sizes are often just used for marketing purposes.
p.s. Speaker manufacturers generally get much fewer warranty claims on subs being in smaller enclosures - due to the damping factor (pressure) being larger in a small box. Some food for thought...

Makes sense as a smaller enclosure would minimize the speaker from extruding to far out or in and thereby reducing chances of tearing away from the basket. Good to know though.

Tell me you have a G5 in your X3? That sub is a monster. I have the 10" DVC low profile driven by a 600 watt Alpine mono block in a .74 cu ft angled box.

I can only imagine the bass you are throwing with that.
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  #214  
Old 02-06-2012, 05:18 AM
deafwish deafwish is offline
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The G5 was a great woofer, but is no longer manufactured by Boston.
I have a Rainbow Hammer 10" and it is a very natural sounding woofer that works exceptionally well in a tiny enclosure (unlike many Boston woofers).

p.s. What is required for an Aussie to "Murder Out" his BMW? I had a mate who's kid had Flo Rider on his iPod - maybe I can qualify? :-p
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  #215  
Old 02-06-2012, 12:21 PM
whiterasta whiterasta is offline
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Quote:
Originally Posted by Evlengr View Post
Rasta two comments/questions for you:

You should get the silver/black carbon fiber roundels for your X3 like I did. See pic

And the box you had made for sub. Is it a single custom box placed in that panel area, or did he just create a facia the sub mounted to?

I ask as my next question would be: Can he make another? I have a 10" Boston Acoustic low profile dvc and I like the way it sounds, but would love to gain the added space by getting rid of the bass box. It's small, only .74 cu ft, but that would be nice come summer time when beach stuff is always in trunk.

I like your set up. However, I opted for a head rest clip on for our iPad, since it plays movies great and can be removed when going to airport or hotel to keep it safe and in use by wife or little one.
It was EV I agree with the roundels. I'm going to be getting a carbon pair this summer. I've blacked out the tail lights as well since this video.

With respect to the sub box. It was created outside and then fit in very snug. I doubt that he would have the specs for it still. I had it done 4 years ago in Toronto and have since move 450km or like 285 miles away from there.

Basically what he did was he used the old piece that was there was cut out and the outside of it was kept. This allows it to still clip in to it's normal spot. He built a steel screen to protect the sub itself and attached it to the plastic. I don't think I've explained it very well I'm sorry. I've put up pictures before that how the set up a little better than the video. I'll see if I can find them.
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  #216  
Old 02-06-2012, 12:26 PM
whiterasta whiterasta is offline
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EV its a custom built single box. It extends a fair distance back. Really cool how he built it.

I've moved from Toronto where it was built. It was built by chase car audio.
But I'm sure any good shop could replicate it.

As for the roundels. I agree with you and will be replacing them in the summer. I've since blacked out the tail lights since the video.

Oh yeah guys you need more than FLOWRIDA to murder her out. Lol.
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  #217  
Old 02-11-2012, 09:03 PM
Bufalo Bufalo is offline
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Okay - alternate topic within the main subject - for those of you who have replaced the head unit, have any of you used one with a flip-down face? I'm impressed with a new Pioneer model, but Crutchfield is saying flip-down-face stereo's won't work in the X3. I'm fearing it's because of the way they set back from flush in the dash kit, and the fold down wouldn't have clearance to open. Anyone with hands-on experience one way or the other? I have an alternate stereo picked out in the case the one I really want just won't work, but I'd love to hear from some others who've tried it already!

GM
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  #218  
Old 03-04-2012, 02:36 AM
x3oiler x3oiler is offline
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Well, the Alpine PXE-650 is installed with a four channel Pioneer Amp. (The Focal solid 2 is put to one side for now). The PXE is running the front door speakers as the high range and the under seat subs as the low range with a 250Hz crossover set in the PXE. The head unit fader is set 100% to the front so not using the rear door speakers (well for PDC only). No "sub" connected as far as the PXE is concerned.
Still playing with settings but it sure fixes the bass. Stage presence is quite wonderful. Can use the head unit volume control after the EQ is conplete and the PXE remote used to set the upper volume as the business CD HU has no volume dependent EQ (e.g. loudness) that will upset the PXE.

The kit is still sitting loose in the back (well tied down but a mess). Will tidy it all up when I am happy (maybe never :-). Both will fit in the hidden area just behind the rear seats - this is why I got the smallest Pioneer Amp I could get - advantage of class D units - very compact.

One thing to note: I tapped into the front door speakers using the junctions in the back side storage cavity where the series capacitors are stored. Very easy to route cables from here to the hidden area.
Be warned, the two sets of cables are wired differently. Once you sort out the speaker connection from the head unit connection then the connections are reversed on the other plug. (use an ohmmeter and look for 5 ohms to find the speakers).
Rear most connections - large connector is the right front door speaker (the small is from the head unit).
Forward connections - small connector is the left front speaker.
Anyway, now that the PXE is wired in, lost of scope to play.
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Last edited by x3oiler; 03-04-2012 at 02:45 AM. Reason: four channel not two
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  #219  
Old 03-04-2012, 10:59 AM
PSUEng PSUEng is offline
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Would someone be able to post the wire colors for polarity on the FR/RR door speaker wiring? Also, any thoughts on how to tap the speaker inputs to the Amp for line level converter to run an aftermarket amp without cutting into the harness?
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  #220  
Old 03-04-2012, 11:19 AM
Supercourse Supercourse is offline
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Quote:
Originally Posted by PSUEng View Post
Would someone be able to post the wire colors for polarity on the FR/RR door speaker wiring?
Here's an alarm/remote start reference on wire color codes (for an '04 - may have changed a bit for '07):

http://www.bimmerfest.com/forums/sho...79&postcount=3

If speaker terminals are not marked (hard to read) +ve and -ve, the larger terminal is normally the +ve - otherwise you have to do the 9V battery test.

Last edited by Supercourse; 03-04-2012 at 11:30 AM.
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  #221  
Old 03-05-2012, 12:35 AM
alexsih alexsih is offline
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Help: I cant find the caps

I've looking for the caps so I can remove them, can you provide some guidance or maybe a pic?

Thanks,
alex

Quote:
Originally Posted by x3oiler View Post
Well, the Alpine PXE-650 is installed with a four channel Pioneer Amp. (The Focal solid 2 is put to one side for now). The PXE is running the front door speakers as the high range and the under seat subs as the low range with a 250Hz crossover set in the PXE. The head unit fader is set 100% to the front so not using the rear door speakers (well for PDC only). No "sub" connected as far as the PXE is concerned.
Still playing with settings but it sure fixes the bass. Stage presence is quite wonderful. Can use the head unit volume control after the EQ is conplete and the PXE remote used to set the upper volume as the business CD HU has no volume dependent EQ (e.g. loudness) that will upset the PXE.

The kit is still sitting loose in the back (well tied down but a mess). Will tidy it all up when I am happy (maybe never :-). Both will fit in the hidden area just behind the rear seats - this is why I got the smallest Pioneer Amp I could get - advantage of class D units - very compact.

One thing to note: I tapped into the front door speakers using the junctions in the back side storage cavity where the series capacitors are stored. Very easy to route cables from here to the hidden area.
Be warned, the two sets of cables are wired differently. Once you sort out the speaker connection from the head unit connection then the connections are reversed on the other plug. (use an ohmmeter and look for 5 ohms to find the speakers).
Rear most connections - large connector is the right front door speaker (the small is from the head unit).
Forward connections - small connector is the left front speaker.
Anyway, now that the PXE is wired in, lost of scope to play.
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  #222  
Old 03-05-2012, 02:43 AM
x3oiler x3oiler is offline
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Inside the left rear storage. The one with the cover that is removable that normally holds the NAV, DVD etc. The looms are at the top. The caps are small - wrapped in the foam that is sealed with velco. Will do some photos tomorrow. There are two caps. One toward the rear of the looms and one closer to the wheel arch. My caps are now gone but I can point out the detail. Note I have business CD - no DSP - no AMPS etc - very basic. If you have other head unit then you need to check here:

http://wds.spaghetticoder.org/en/e83.../Sound_output/

You can get pictures from here as well e.g. click the link near the caps in series with the front door speakers. e.g. http://wds.spaghetticoder.org/en/zin...83_65_0034.htm









A sharp tool and bit of gentle leverage is the easiest way to get the connector apart.



The rear connector set and the connector TO the front right door speaker is shown, as is the connection FROM the head unit. The connections are reversed in the front set of connectors.



The capacitor will look something like this but smaller - this was my replacement before removal altogether

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Last edited by x3oiler; 03-05-2012 at 08:32 PM. Reason: Pictures added.
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  #223  
Old 03-06-2012, 01:45 PM
alexsih alexsih is offline
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Thanks for the pics, much appreciated.
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  #224  
Old 03-06-2012, 05:11 PM
PSUEng PSUEng is offline
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Wow I must have missed something here---what is the purpose of the capacitors?
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  #225  
Old 03-07-2012, 02:05 AM
x3oiler x3oiler is offline
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In the Aussie spec. business CD, the front speaker output drives the under seat and the doors in parallel. Both sets are 4ohm thus combined 2ohm. But. The door speakers have a series capacitor (mounted in the rear as shown above) to cut the bass to the door speakers. So at low frequency the door speakers are effectively isolated by the caps and the HU "sees" 4ohm under seat speakers only. At high frequencies the caps are effective short circuit and the door speakers are fully in parallel with the under seat for combined 2 ohm. Why is the question. Guessing that this limits the power to the under seat speakers at the low end for HU protection? - just guessing.

Why I changed to 300ohm? To get approx 200Hz low frequency rolloff when I put in the earthquakes. The earthquake at that time were driver from a low pass amp cos they do not handle full range and I did not wan the doors low end interfering with the earthquakes.
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