Carver subs

[yg54sg]

On the way back tonight I was playing around the with the DSP settings the subs behind the seats over the last couple of years have been making distorted noises on sub bass passages, infact ever since the car being new they have distorted on some songs. I decided to whip off the grilles and take a look. There is no cone damage and the distortion just appears to be vibration, I was always under the impression that when you faded to the rear the subs were not included and they were wired with the fronts. It seems they work with both rear and front as I can visually see the driver thumping in and out when set front or rear.

I hate to say it but even with deep deep rnb music these subs are bad! All the nice bass 50hz up 95% of what you can hear and feel comes from the front kick panel bass speakers, these carver rears just produce a fart here and there, if you set the fader to rear and the DSP on the first bar (80hz up full) the rest fully down crank the bass full in settings then turn off treble off purely to listen to the bass then pan from front to back you can clearly see those carver speakers having the crap knocked out of them with little sound or pressure in the cabin when set to rear, if you place your head near the windscreen you then begin to hear them and how deep they are. .... I wonder if anyone else's does this? It seems to me the these rear carver speakers are masked by how good the front bass speakers are the enclosures are too small for the frequency's the are being expected to reproduce. I have seen threads saying the carver speakers are not working and people replacing them I wonder how many of those people have replaced them to find there is no difference and the driver was good in the first place?

Would be great if someone with a carver system could whip thier carver grille off and do the same as me above. I wonder if power from the amp is low to them or if they are generally just bad. Sometimes when i drop the roof the bass sub level increases but I put this down to acoustics and the strange thing is it does not always happen...

 

[Hotride]

I have the carver system, but no such issues - the speakers behind the seats provide great bass, gives me a nice kick in the back no matter what music I'm listening to. (generally something electronic like deadmau5 or pitbull) If i turn them up too far, the whole car gets the vibration noise (i need to buy some dynamat tbh) but I find the subs to be great, maybe your system has some kind of problem??

I guess you could have a dodgy amp or sumthing, but my system definitely ain't like yours, and I find it rather impressive for an OEM setup. Hope you get the issue sorted

 

[yg54sg]

thanks, my system also gives me the kick in the back but 95% of that kick is coming from the front bass speakers, but as you say maybe there is a problem as quite a few times with the roof off its impressed me but not for a while... I guess i need to listen to another carver system and compare anyone got a carver system around sheffield?

 

[ZED_NOT_ZEE]

I'm with Hotride on this one. It's nowhere near what my e36 is pushing (with 3 JL 10W6V2's), but for a stock setup it's not bad. I did a lot of tuning and playing with it when we initially purchased the Z4. The rear subs do not continue to move when panning to the front speakers. I also notice no distortion at all, and I do like my bass.

Now something to note is both Hotride and I have 3.0i's. I'm assuming Hotride's car is also pre-2006 (prefacelift) which actually has a different Carver premium HiFi setup than the facelift cars. In fact, there are number of threads about how much better the pre-2006 models HiFi setups are. Not sure how true it is, but post-2006 are THX certified setups.

What your describing though sounds a lot like the speakers are playing out of phase. Maybe try taking one of the rear subs out and swapping the terminals, or even just taking one of the wires off to see if the situation increases.

 

[sully]

Your description of the the Carver subs is exactly how mine sound.....absolute pap.......

 

[nick_z4]

The sound from my Subs is fine as well, gives a good kick and a nice rumble and ive been through the whole boy racer stereo thing years ago (never again!). But i'm surprised by how reasonable the sound is from this system.

 

[glastoveteran]

I'm confused - are there two different types of subs - those that come with the Logic7 system and those that come with the Hifi / Carver system?

 

[jimbo1958]

The sound from my Subs is fine as well, gives a good kick and a nice rumble and ive been through the whole boy racer stereo thing years ago (never again!). But i'm surprised by how reasonable the sound is from this system.

Same here......really pleased with the Carver.

 

[ZED_NOT_ZEE]

The sound from my Subs is fine as well, gives a good kick and a nice rumble and ive been through the whole boy racer stereo thing years ago (never again!). But i'm surprised by how reasonable the sound is from this system.

Same here......really pleased with the Carver.

what year is your car?

 

[jimbo1958]

The sound from my Subs is fine as well, gives a good kick and a nice rumble and ive been through the whole boy racer stereo thing years ago (never again!). But i'm surprised by how reasonable the sound is from this system.

Same here......really pleased with the Carver.

what year is your car?

04

 

[Hotride]

Well looking at this thread it does seem the pre-facelift owners are much happier with the carver system then the facelift owners. Seems crazy they would change it for the worst lol. OP is yours pre or post facelift?

Maybe you face lift drivers should retrofit the pre-facelift system

 

[ZED_NOT_ZEE]

Definitely different systems according to realoem.com. The switch happened with production vehicles of 01/2006.
Different part numbers + prices for the amp. The subwoofer changed part numbers in 04/2007.

Pre-2006: http://realoem.com/bmw/partgrp.do?model=BT53&mospid=47799&hg=65
Post-2006: http://realoem.com/bmw/showparts.do?model=BU33&mospid=49304&btnr=65_1219&hg=65&fg=20

I believe the change in the system was made specifically to meet the THX Certification for 2006 models. BMW was boasting and dropping press releases back in '06 that they had the first european vehicle that is THX certified in '06.

Here's an article: http://www.mwerks.com/artman/publish/bmw_news/article_1009.shtml

 

[yg54sg]

OK perhaps its just me expecting more from them than they actually do Dont get me wrong the system sounds great for what it is but those subs specifically are what I was wondering about they dont sound too great or do much even with dance/rnb music. If you compare what a home 6.5" driver can do from say a top brand like B&W these carver subs are not putting out any where near the level they would be they are also not ported and sealed enclosures are pretty poor for effciency. I removed one to check for poliarity/phase issues and the plugs can only go round one way, with one disconnected there was no increase in sub bass it descreased so not a polarity issue. I had an old hifi floor standing speaker dual 6.5" cones, i disconnected them and rewired the box in series to give an exact 10 ohms, placed the whole box in the boot wired them up to the plug of one side of the carver sub and got window shaking bass... too much infact so the amp is not the problem! Since my boy racer days are also over (and i like having a boot) i removed it shortly after

The bottom line is the carver subs do a great job with the space provided to them and I was shocked at the internal volume of them...they sound (or rather from cone movement) look as if they are looking after 20hz to 50hz the box they sit in is tiny and i doubt offers the proper acoustic coupling needed to amplify these frequencies in any large way for that driver... all the box is doing is providing air pressure to stop that 30v long stroke cone from bouncing out of the voicecoil gap lol IMO! The real bass and all the chest pounding action is coming from the carver front 50hz and above bass speakers, most people could probably completely disconnect those subs and would not notice! I will however try and listen to another carver pre 2005 system for peace of mind as i cannot be sure the level going to these subs is at fault, it doesn't appear so though with watching them and the tests i have done.

I experimented with the roof up and down and it seems the sub bass is amplified a little with the roof down I imagine due to acoustics in some way (which is strange as it should be the opposite) what made a huge amount of difference was playing with the DSP / Bass/Treble settings and source input. It seems there is a limiter of some kind working so it you push up one frequency it will reduce power to the rest to compensate. In the pro audio world (stage not car audio) limiters would be placed on each crossover band at the amp stage e.g bass/sub would have one limiter, mid another and high another, seems as though they have put one compressor/limiter on the entire signal fed to the amp so the individual amp channel may not even be at maximum volume before clipping e.g like the subs .

 

[ZED_NOT_ZEE]

If you compare what a home 6.5" driver can do from say a top brand like B&W these carver subs are not putting out any where near the level they would be they are also not ported and sealed enclosures are pretty poor for effciency.

Hmm, good point. My Monitor Audio's use 6.5"'s and have pretty good bass response. I wonder why they didn't just make it a ported box if the subs are used more to increase air pressure than sound quality.

20hz to 50hz sounds about right to me. I noticed similar with my subs.
Would still love to upgrade them though if I could find something better that fit in there. Or if the enclosure/box was ported.

From what you describe it sounds basically like Logitech 6.5" computer subwoofers. Small subs in small plastic boxes.