Subwoofer issue

[The Lexus Enthusiast]

Hi everyone,

Recently purchased a cassette tape adapter and have been playing songs from my phone to the standard Mark Levinson audio system. The other day I forgot to turn down the CD before switching to the tape and the music from the phone came on incredibly loudly. I immediately turned it down, however I instantly noticed that the bass seemed to be almost gone. I thought at first that my own ears were just a bit shocked  but ever since it happened there seems to be a considerable reduction in bass.

Earlier today when we got home I played some music from a CD in the changer and turned it up. I sat in the back of the car and realised that all the bass that was present seemed to be coming from the rear door speakers and only a tiny amount from the actual subwoofer which was kind of muffled. 

Has my subwoofer become damaged/blown in some way?

I was also using an equaliser on Spotify app to play music and had the EQ set at maximum bass to make up for the sound performance on the cassette adapter for a day or two until I realised what a bad idea that was for the speakers Have I damaged something?

Any advice much appreciated, thanks,

Alex 

[Shiner]

Possibly the paper cone is torn..

If you can take the top cover off, gently with a screw driver  or similar, on the subwoofer on the rear seat shelf under the rear glass shield. Then gently , very gently, run your finger around the cone...if you find a tear. Stop.

get some colourless silicon , small tube , and apply it generously to seal the tear.  Better still , seal it all around the paper cone close to the tear.  Be careful not to let silicone get on the shelf or leather...then wait for it to dry.

Next day try the music...if it works put the cover back on and enjoy. If not then...it could be an expensive job.

 

There is a thread on this topic...but I think it’s on the US club.

 

good luck...It worked for me a few yrs ago...

[The Lexus Enthusiast]

Thanks for replying,

This too happened to me twice! Unbelievable that they make these things out of paper!

Unfortunately it isn't making that torn sound so I think it's something more serious, perhaps the entire speaker has just blown or something? Luckily I have the old subwoofer so I might mend it with silicon and get someone to fit it if all else fails.  

Alex 

[Bluesman]

1 hour ago, The Lexus Enthusiast said:

Thanks for replying,

This too happened to me twice! Unbelievable that they make these things out of paper!

Unfortunately it isn't making that torn sound so I think it's something more serious, perhaps the entire speaker has just blown or something? Luckily I have the old subwoofer so I might mend it with silicon and get someone to fit it if all else fails.  

Alex 

Although they call it paper it's not made out of old newspapers it's specialised acoustic card which has been used for years. Some high-end audios come with thin aluminium cones but they don't have the same warmth you get from a card coned speakers.

[The Lexus Enthusiast]

1 minute ago, Bluesman said:

Although they call it paper it's not made out of old newspapers it's specialised acoustic card which has been used for years. Some high-end audios come with thin aluminium cones but they don't have the same warmth you get from a card coned speakers.

You learn something new every day!

I remember watching a video on Youtube years ago about Mark Levinson explaining just how many tests they conducted to select just the right grain of leather that would have the best acoustic effect! Personally, I'd be prepared to forfeit a bit of sound quality to have longer lasting more durable speakers though  especially since this is the third speaker that has gone wrong in the car over about 3 yrs and we never listen to anything at skull shattering volumes. 

Alex 

[mrdoofa]

Paul Frost is selling these direct replacements for the subwoofer on eBay, could be worth considering.

https://www.ebay.co.uk/itm/Lexus-Ls430-Upgraded-Factory-Fit-Subwoofer-Speaker-800w-Facelift-New/202266957057?hash=item2f180cd501:g:-WAAAOSw4shYAgRP

[messi]

If i was you, I would just replace it with a good quality aftermarket sub. You can fix the old one, but it will tear again, then you've got to go through the same routine of getting the sub out etc etc. Me personally, I think the mark levinson sound system isn't that good anyway, I prefer the premium sound system, but each to their own. Replace it for a Denon sub or Alpine, at least it will last much much longer

[The-Acre]

1 hour ago, messi said:

If i was you, I would just replace it with a good quality aftermarket sub. You can fix the old one, but it will tear again, then you've got to go through the same routine of getting the sub out etc etc. Me personally, I think the mark levinson sound system isn't that good anyway, I prefer the premium sound system, but each to their own. Replace it for a Denon sub or Alpine, at least it will last much much longer

I agree, I've not found the ML to be any better than the Lexus premium sound system, or maybe you need a better ear for music to appreciate it.

[The Lexus Enthusiast]

Thanks for all the advice. 

I once read somewhere that using an aftermarket sub might damage the amp? Not sure wether that's true though, but an upgraded sub is tempting since if I mend and reinstall the old one it will probably just tear in a few months. Mind you, I have a feeling that the sub isn't actually torn because I don't hear that usual popping sound. 

I haven't listened to a standard Lexus sound system so can't personally judge, but it seems that although the ML sounds great, at times it can be too powerful and just end up wearing out speakers and usually the bass drowns out other frequencies especially when you have to turn it up on the motorway. 

 I will probably  think about it and either fix and reinstall the old one or splash out on a new sub.

Thanks, 

Alex  

[PJD]

You don't need to take the subwoofer out to fix it, - just run rubber-glue around the rim in situ, after removing the cover

[The Lexus Enthusiast]

How should I remove the cover so I don't break anything?

 

Alex 

[steve2006]

Wallpaper scraper to prise up the edge nearest the seat lift up and off.

 

[The Lexus Enthusiast]

Just now, steve2006 said:

Wallpaper scraper to prise up the edge nearest the seat lift up and off.

 

Sounds simple enough so long as it will clip back on and not rattle.

Thanks,

Alex 

[DaKa]

It's hard to fix the problem without removing/replacing the speaker, but everything above is true if you are good with a silicone gun and keep the volume at a reasonable level.

Mine has the 8" foam detach from the rim creating the blown sound effect and I did order some special glue and replacement foam rings with the intention of removing and carefully fixings. After many months of the bits sitting on my garage shelf I decided to buy an aftermarket sub based on some youtube searching from USA - I'm awaiting delivery of the Polk Sub purchased from amazon.

It will mean removing the seats and some trim as shown in the couple of clips but I'm hopeful of a longer lasting result?

 

 

 

[Cotswold Pete]

I would recommend that if you have to take it out to repair, then it is best to actually replace the unit, so long as it has roughly the same electrical character, not just impedance, but effeciency (measured in dB/Watt) and possibly Q factor (measure of damping) to ensure cone does not resonate (peak bass) at same frequency that excites the parcel shelf (as example).

If not matched you could get too much or little bass, or some booming with some intruments.

Modern speakers have much better glues and build than something from 10-15 years ago, so a repair is only worth doing if you really really like the sound of the speaker, and I would guess the original LS is not  that high a grade compared to the speakers of 2018.

Looks like the Polk DB840 is a bit hard to get hold of, so not sure what would be the option here, maybe someone else on forum has tried other options in a 430

[messi]

17 minutes ago, Cotswold Pete said:

I would recommend that if you have to take it out to repair, then it is best to actually replace the unit, so long as it has roughly the same electrical character, not just impedance, but effeciency (measured in dB/Watt) and possibly Q factor (measure of damping) to ensure cone does not resonate (peak bass) at same frequency that excites the parcel shelf (as example).

If not matched you could get too much or little bass, or some booming with some intruments.

Modern speakers have much better glues and build than something from 10-15 years ago, so a repair is only worth doing if you really really like the sound of the speaker, and I would guess the original LS is not  that high a grade compared to the speakers of 2018.

Looks like the Polk DB840 is a bit hard to get hold of, so not sure what would be the option here, maybe someone else on forum has tried other options in a 430

I agree. In a few months time your going to probably have to repair it again, just replace it with a better subwoofer, in my opinion Mark Levinson speakers are not that good anyway, get a Denon or an Alpine

[Shiner]

I repaired mine in situ...about 2 yrs ago..no problems since. But silicon gun won’t help! The access is too restricted. You’ll have to use your fingers and as small a silicon tube as you can find. Make sure u have water in a bowl to wet your fingers and plenty of kitchen paper towels to wipe off the access.

its not difficult but fiddly...practice on a piece of surface outside the car before u tackle the job.

 

removing the sub is not an easy job..involves having to take the back seat out! 

[mrdoofa]

Taking the back seat out isn’t that difficult, there are numerous “how to’s” on the web explaining the process, only a handful of screws and bolts and a couple of electrical connections. I read somewhere that the job is possible without removing the seat. Apparently you can lever the shelf up enough without removing the seat, apparently the parcel shelf will bend but not break whilst doing it!!! I’ve never tried it though so do that at your own risk lol!!! The music I listen to is very bass heavy so a working sub is a must. Mine does have a slight rattle developing ( probably because I overdid it a bit!!!) and am considering one of the ones from Paul Frost on eBay as they are straight plug and play replacements and are supposed to be an upgrade from the original.

[DaKa]

So as per my post on 27/3 my Polk sub woofer arrived from USA this week (it only took about 10 days from order to delivery amazon total cost circa £65) and I've fitted it today as per the youtube link instructions above.

The sound is back to amazing (better than I ever remember the bass) and the quality of the new speaker (if judged by the weight) is 3-4 times better than the factory stock Levinson. I don't profess to understand the 4 to 8 ohms thing, I just followed the wiring instructions using some quality speaker wire from Wilkos. 

Only 3 problems,

1) The rear offside single bench seat had two push in connections for the base and pulling it up wasn't enough. I had to get low peer inside and put a long screwdriver in to wedge the seat out from the push fittings made easier with the wider near side base bench seat removed first.

2) I removed and disassembled the old speaker but then had to keep checking back the youtube post to remind myself which way round things had to be refitted - I found it best to remove 4 small sections of the raised edge of the new speaker metal rim so that the original Lexus part used to secure the speaker with 4 grub screws could be used again. Removing the plastic cover rim from the new speaker required a small screwdriver to force them apart as it had a silicone seal between the metal and plastic rim. Cutting the raised metal 3mm rim on the new speaker was simple enough, just a small hacksaw cuts 1 cm apart and then pliers to bend back forward until the raised rim broke away creating a flush fit.

3) The quarter side panels were a pig to remove but there is definitely a knack to it as mentioned in the youtube.

The Polk came with a gasket that works well between the old 4 bolt fitting bracket and the new speaker, some small silicone or gasket seal between the top of the new speaker metal rim and the original Lexus plastic rim at the top of the speaker is optional but I recommend it. 

Definitely a DIY task, it took me about 3-4 hours start to finish but half of that was the quarter side panels either side of the rear shelf and removing the single bench seat (I didn't want to force and break something).Tools needed: 10/12 mm sockets with 6-8 inch extension rod, medium/small screwdriver, panel prising tools, electrician wire cutter tool and red/blue connectors 

P.S. Pack your socket with a little grease so that you don't drop the 12 mm fixing bolts when refitting through the small access hole near the rear head rests that should be raised but not removed. It also helped to have the rear seat slightly reclined so the access hole and the bolts line up better.

I must confess that half way through the job I was regretting starting it (there's a lot of stuff packed into those rear seats so take your time) but once it was all done with everything working I was delighted with the results and cost saving.