[spta97]

I purchased the full Bavsound speaker set (subs and mids/tweets) and am very happy with the overall improvement.

However, I am having one issue with the Ghost subs (both sides). They are making a rattling noise on certain bass notes.

I am currently working with Bavsound to resolve, but I wanted to see if anyone else had this issue.

The noise is present with the sub outside of the enclosure (i.e.; it's not part of the car rattling), as well as with different sources (I noticed initially when streaming through CarPlay but had the same issue with a compact disc).

Initially they said it was distortion so I turned down the bass and EQ to flat and still hear it.

I'm curious if anyone else has ideas or has experienced this before?

Below is a vid of the sound.

(you can hear it at :10, :17, and :24 seconds)

[BMWZ4]

Weird, but no I don't know where that rattle is coming from. If I didn't know better I'd say it was from the track itself, but I'm guessing you've tried other similar tracks with the same result?

[spta97]

Originally Posted by BMWZ4

Weird, but no I don't know where that rattle is coming from. If I didn't know better I'd say it was from the track itself, but I'm guessing you've tried other similar tracks with the same result?

Correct. I've also played the song on my home theater with no rattle.

I've also played other songs which replicate the rattle. It doesn't happen on all but mostly bass heavy songs.

I can eliminate it by completely removing the bass but that defeats the purpose of subs

[BMWZ4]

Stumped. I thought maybe a cracked grille but you mentioned the vibration is in both sides, so that couldn't be the issue. I suppose a hardware defect.

[spta97]

Originally Posted by BMWZ4

Stumped. I thought maybe a cracked grille but you mentioned the vibration is in both sides, so that couldn't be the issue. I suppose a hardware defect.

I was informed the metal grills are removable so I'm going to take one out this weekend and see if there is anything going on with the grill or inside.

I really hope I can find the root cause (and it is not the design) as they sound great otherwise.

I plan to install a sub and amp in the hatch so the ghosts would be perfect for punchy mid-bass.

[suby01]

Okay yeah I am not an audiophile Im sure there are many other members that have so much more audio knowledge than me. But thats not a rattle. Thats clearly a defective speaker or sub. Either something with the actual speaker area itself, could be even the magnet. Go ahead and try removing the grills as a test. But you might as well ask for a replacement pair of speakers in the process.

[spta97]

Originally Posted by suby01

Okay yeah I am not an audiophile Im sure there are many other members that have so much more audio knowledge than me. But thats not a rattle. Thats clearly a defective speaker or sub. Either something with the actual speaker area itself, could be even the magnet. Go ahead and try removing the grills as a test. But you might as well ask for a replacement pair of speakers in the process.

That's what I'm thinking as well. They offered to replace at first but I want to ensure it is an actual problem and not an issue with the speaker design.

What worries me is it is both speakers doing it. I could imagine one defect but both makes me worry it is something with the design (or perhaps a bad lot/batch?).

Bavsound has been good to deal with thus far. I've been emailing with them and sent them updated videos with a different source (CD) and bass flat on EQ and boost where it still made the sound.

Thanks for the input!

[BMWZ4]

Agreed probably a defect, even if it's the pair. I also don't believe it's a design flaw since others would've likely reported something by now. Keep us posted.

[spta97]

Originally Posted by BMWZ4

Agreed probably a defect, even if it's the pair. I also don't believe it's a design flaw since others would've likely reported something by now. Keep us posted.

Fingers crossed and will do

[Alias1431]

You torque those screws down enough?

Also, download a frequency generator app for your phone and play through car bluetooth. Way, way easier to locate and diagnose rattles.

[spta97]

Originally Posted by Alias1431

You torque those screws down enough?

Also, download a frequency generator app for you phone and play through car bluetooth. Way, way easier to locate and diagnose rattles.

GREAT idea on the frequency generator!

Screws are torqued down tight but I also removed the speaker from the enclosure to eliminate the car from the equation (I could hear it while holding the speaker in my hand).

[suby01]

Originally Posted by spta97

GREAT idea on the frequency generator!

Screws are torqued down tight but I also removed the speaker from the enclosure to eliminate the car from the equation (I could hear it while holding the speaker in my hand).

Youve blown your speakers. I dont know if the BS speakers have a break in period as most aftermarket subwoofers do. Or they were just defective from the factory. Anyway if youre hearing the same thing with them outside the enclosure they are fried, which sums up my first initial post that was hard to decipher from a online recording.

[Oldguysrule]

Sounds like the voice coil on the speaker cone is rubbing on the core. Most likely over driven if its present on both speakers. Inspect the cones for possible tears. If you have a digital multi meter measure impedance between + and ground. You should get 4, 6 or 8 ohms. If you don't get anything, speaker is shot. Does it do it with just one source or multiple sources??

[sinbad4]

Originally Posted by spta97

I purchased the full Bavsound speaker set (subs and mids/tweets) and am very happy with the overall improvement.

However, I am having one issue with the Ghost subs (both sides). They are making a rattling noise on certain bass notes.

How are you playing your track? From Phone over Bluetooth? Aux in? USB?

[Alias1431]

Also, this goes for anyone, make sure your EQ is flat when you start playing music after installing the new ones. Not only for break in, but because they're a lot easier to drive than the stock ones.

[Tchgrif]

I also play a lot of bass heavy music in my x4 with complete bav sound upgrade save the amp, which still isn't available, and I do not have this issue. I would say to check how you bolted them down as you have to install them with bolts and nuts once you hammer out the old ones but i guess you have that even with them out of their enclosures. maybe when they are out hook them up and see if you can see if something extra is fluttering around? otherwise I would say you got a manufacturing defect probably where the magnets attach to the cones or the magnets themselves are not moving properly.

[spta97]

Originally Posted by suby01

Youve blown your speakers. I dont know if the BS speakers have a break in period as most aftermarket subwoofers do. Or they were just defective from the factory. Anyway if youre hearing the same thing with them outside the enclosure they are fried, which sums up my first initial post that was hard to decipher from a online recording.

I heard this from the initial install where I just turned on the volume low to hear if they worked. They could be blown, but I don't think I blew them.

Originally Posted by Oldguysrule

Sounds like the voice coil on the speaker cone is rubbing on the core. Most likely over driven if its present on both speakers. Inspect the cones for possible tears. If you have a digital multi meter measure impedance between + and ground. You should get 4, 6 or 8 ohms. If you don't get anything, speaker is shot. Does it do it with just one source or multiple sources??

Great advice - I will measure this weekend (they are 8 ohm speakers) while I am taking the metal grills off (I did not realize they were removable) to inspect for damage.

Originally Posted by sinbad4

How are you playing your track? From Phone over Bluetooth? Aux in? USB?

This was through bluetooth and a CD in the dash so I eliminated the source as the issue.

Originally Posted by Alias1431

Also, this goes for anyone, make sure your EQ is flat when you start playing music after installing the new ones. Not only for break in, but because they're a lot easier to drive than the stock ones.

Good advice.

Originally Posted by Tchgrif

I also play a lot of bass heavy music in my x4 with complete bav sound upgrade save the amp, which still isn't available, and I do not have this issue. I would say to check how you bolted them down as you have to install them with bolts and nuts once you hammer out the old ones but i guess you have that even with them out of their enclosures. maybe when they are out hook them up and see if you can see if something extra is fluttering around? otherwise I would say you got a manufacturing defect probably where the magnets attach to the cones or the magnets themselves are not moving properly.

They are secure but I will be checking the voice coil/surround/magnet this weekend.

I'm still within the 100 days and Bavsound recommended sending me a new set of woofers but I still want to troubleshoot to find the root cause.

I like the way the entire system sounds outside of this rattle. Hopefully the new pair will resolve it.

[spta97]

I received the replacement Ghost Subs and did some testing this weekend. Keep in mind I have my ear right near the sub so these sounds may not be heard if sitting in the seat. I am also very sensitive to sound.

Troubleshooting: - Bass was set to flat on EQ and minus 2 clicks on the boost
1) Removed the metal grill from the rattling ghost subs and subs from the enclosure - the rattle persisted.
2) Tested the resistance of both the Ghost Subs in the vehicle as well as the new ones received - both measured 6.8 ohms (interesting as I thought they were 8 ohms but I guess they lowered the resistance to get louder sound like the Bimmertech subs).
3) Installed new subs - rattle persisted.
4) Tried a frequency generator - It seems the issue happens around 100-150 Hz . The bass gets sloppy and I get the rattling under the threshold (note: I have to get exact frequency as I was having CarPlay connectivity issues and a ran out of time).
5) Installed the factory sub and got a similar rattle/woofer muddiness on the same songs.

Findings:
1) I have come to the conclusion that the Ghost Subs (and factory) are just incapable of reproducing low bass frequencies below ~150hz (again, exact frequency TBD). They try but the sound falls apart.
2) As a result the bass becomes muddy/rattles the subs.

Proposed Solution:
1) I do like the mid bass punch of the Ghost Subs, so I was thinking of getting "Bass Blockers" to filter out the low frequencies from the Ghost subs.
2) I intend to install a dedicated JL Audio 500/1 amp and HO 10" ported sub box which will fill in the filtered frequencies.

Other Options:
1) I wonder if I would have better luck with another OEM replacement sub? I am limited to 7-8 ohms so I think the only other is Bimmertech AlphaOne.

For reference, I have an X3MC with the HK system.

Opinions appreciated

[Wgosma]

I think you might do well to install the add'l amp and large subwoofer speaker and then consider the under seat speaker situation.

That larger speaker is going to cleanly pull in the lows-

[spta97]

Originally Posted by Wgosma

I think you might do well to install the add'l amp and large subwoofer speaker and then consider the under seat speaker situation.

That larger speaker is going to cleanly pull in the lows-

Agreed. However, I typically like my subs to have a low crossover (like 40 hz). I'm willing to go up to 100-150hz but any higher than that I'm concerned it will not perform the way I want.

I'm also somewhat committed as I've already pryed the factory subs out of the enclosures and if I put them back in I'll have to silicone them which would be a PITA to remove.

[Wgosma]

Originally Posted by spta97

Agreed. However, I typically like my subs to have a low crossover (like 40 hz). I'm willing to go up to 100-150hz but any higher than that I'm concerned it will not perform the way I want.

I'm also somewhat committed as I've already pryed the factory subs out of the enclosures and if I put them back in I'll have to silicone them which would be a PITA to remove.

Agreed in the low crossover freq; maybe push it to 125 Hz.

Darn bad luck in the under seat units, hmm...

[suby01]

So they new replacement speakers no longer rattle then correct? Meaning the first ones were defective?