I have had soundproofing carried out to the boot, rear tyre well, wheel arches, all four door panels however I am still getting noise from the rear of the car.

Its a kind of whistle as though the door seals have gone (had the door seals checked at main dealer, they are fine)

If I am driving on a concrete type of motorway I can hear the noise however if I go over a tarmac section the noise dissipates by over50%.

This is lead be to believe that its either tyre noise and-or exterior wheel arch noise. 

I am having hancook 67bd tyres fitted on Tuesday, the ones I have fitted at the moment are 70db.

Is it worth me asking the tyre fitter to remove the canvas material above the wheel and using some kind of sound deadening spray or silent coat on the exterior wheel arches or would it fall off due to damp?

 

Thank you

Anyone used this?

 

 

https://www.buzzweld.co.uk/lizardskin-sound-deadening.html

The decibel number on the tyre label is the noise level heard from outside the car as it drives past, and does not necessarily relate to what you'll hear inside the car.

Thank you for the reply

 

Yes I understand that the db level is  rated from outside however if something is noisier outside it is usually heard more inside in the same way as a waggon going past your house that is fitted with double glazing will be heard less than an electric car.

As I have tried everything else, the only option is to change tyres or soundproof the exterior.

 

There is an option for soundproof ing the exterior wheel arch with a spray. this is the link, has anyone used it?

 

https://www.buzzweld.co.uk/lizardskin-sound-deadening.html

Have you removed the rear wheel arch liners and added silent coat and closed cell to those areas?

The main topic on all this is here FWIW

 

https://www.briskoda.net/forums/topic/449490-noise-insulation/

 

Wheel arches are far less important than doing the boot floor and sides with sound deadening material. This area acts like a big speaker driver. 

 

I have done the front and rear wheel arches and sprayed the rear felt covers with a rubber dip compound to increase their density and durability. 

 

I am not convinced much noise gets into the car directly from the wheel arches. Its mainly sympathetic vibrations in the panels in other parts of the car from mechanical vibrations.

 

https://www.youtube.com/watch?v=676P7bIV0Gg

Edited 3 July, 20205 yr by digifish

Just to clarify ... cabin noise is mainly mechanical vibrations from the tyres making its way into the suspension and then into the bodywork, which re-radiates into the cabin. Hence why dampening the panels from the inside can have an impact.

 

I don't believe the tyre-to-air-to-wheel-arch is a particularly major path for noise.

 

Example. The sill channel below the doors, would pick up more noise and vibrations and does re-radiate directly into the cabin up the B pillar. 

 

And then there is wind noise of course. 

Edited 3 July, 20205 yr by digifish

Ahhh I see

 

I have had the doors done but not the B pillar however the noise seems to be emanating from the rear, even when I'm sitting in the back seat?

Do you think I should have the pillars done? 

Can anything be done with the cills?

 

 

Thank you

Start here ... the floor that is visible when you remove the boot wheel cover and wheel, of course. Probably the most dramatic change you can possibly do in a Superb III

 

 

Its something you can easily do yourself too. You just need to buy some Butyl Sheets.

 

The B pillar is probably #2 on my list of dramatic changes...nothing like the boot floor, but significant as sound is piped up the pillar to exit around your head and the seatbelt. Anyhow I recommend reading the entire Noise Reduction thread I linked above.

Edited 4 July, 20205 yr by digifish

 

As I said in my original post, I already had the boot bone with silent coat with the addition on a sound deadening mat under the boot mat.

I had a look at the B pillar and seen the word air bag and thought better of it.

It looks like a complicated job to me.

Thank you for the advise it really helps.

 

 

 

 

 

 

 

 

B pillar is a big one for the gains, and very easy to do. Don't worry about the airbag at all. 

 

Prise out the 'Airbag' plastic clip, remove the screw. Then just pull out from the bottom edge of the top trim. It will unclip, then the top of the trim then will slide down and out.  Then unclip bottom trim.

 

From there add your deadening, paying particular attention to fill the cavity down at the bottom of the B pillar and the cill.

 

This really is probably the easiest and most beneficial upgrade.

I describe the process here, although don't show it ... I just notice I say A pillar...but it is B  You are not going to set the Air Bag off, its up in the headliner not in the Pillar.

 

 

Here's Steve's pic of where to stuff foam first...notice it really is a Trumped Bell...super silly not to block this in the factory. The Superb III Sills are big and really resonant too. Soaking up all sorts of outside noise and channeling it into the cabin through this area. Rap them with your knuckle along their length, its quite surprising how thin and undamped this metal is.

 

 

Start reading here

 

 

 

Edited 4 July, 20205 yr by digifish