D90mitch
Well-Known Member
- Posts
- 2,419
So, given a lot of people want to add some form of sound proofing to their Defender, I will share what I think makes the biggest difference. There's not much of my 90 that hasn't been touched in some form.
To begin with, the most effective way to add soundproofing to your vehicle is with two layers. A thin, hard layer and on top of that a soft, closed cell foam. You don't want open cell foam as it will only absorb water. The reason behind the different layers is to absorb different frequencies of sound. Another way in which the harder mat type surface will reduce sound is by increasing the mass of the panel it is adhered to, subsequently reducing vibration and thus noise.
When soundproofing my 90, the first areas I targeted was the front foot wells, gearbox tunnel and the removable panels under the seat bases. As a matter of personal choice, on top of the hard sound proofing in the foot wells, I added sound proofing carpet. I got a large quantity at a good price from Noisekiller at one of the LRO shows. I added closed cell foam under the gearbox tunnel interior cover (the black matting). I also applied the hard mat and foam on top of the under seat panels.
Once finished in these areas, I took the vehicle for a drive and there was a noticeable improvement. I didn't have to raise my voice so high to speak to passengers and the general driving experience was improved.
Happy with the result, I took to soundproofing many other areas of the Land Rover. This began with the rear wheel arches. When I purchased the vehicle it already had some hard adhesive mat down identical to the other stuff I had used so I simply applied some of the acoustic carpet over the top of this. In addition, I purchased a second, thinner rubber mat to lay over the original in the back. The combination of the carpet and the chequer plate style mat made the rear of the vehicle look very smart indeed. The results were also noticeable but not to the extent of the changes made to the front. The floor itself in my vehicle is not carpeted so that it is still easy to clean out if it gets muddy. Instead I have thin rubber floor mats with a harder wearing plastic one on top.
I then moved on to applying the carpet to the ceiling inside the vehicle as I only had a headliner in the front section of the vehicle. Again, this made great improvements to the feel of the inside of the vehicle however no real improvement in sound dampening. Although, I did notice the vehicle seemed to retain heat better in the cold.
The final steps I took to reducing sound in the vehicle were to add sound insulation to the doors and the under bonnet area. Although the doors sound more solid when they close, I unfortunately did not notice much of a reduction in noise which was surprising given the thickness of the foam I used in the engine bay (note this was a foam with a heat reflective surface specifically designed for engine bays).
If the material you are using is not self adhesive, I urge you to use a high temperature spray glue or the material you have applied will likely peel away if the panel is left subject to strong sunlight!
So as a result, I can now talk with a slightly raised voice in a Land Rover 90 with a straight through exhaust system at 60+ on the motorway opposed to bordering on shouting in the 90 when it had no sound proofing and a standard exhaust system! I am sure with a silencer fitted my Landy would be even quieter inside. To be fair, I can barely tell there is a straight pipe unless I open the window... Just need to sort that vibrating exhaust bracket.
Other things you can do to decrease the cab noise of your Defender include:
Choosing better tyres (they don't necessarily have to be road tyres, I have Cooper Discover STT mud terrains and I can hardly notice them) Retreads are often noisy, I have had them in the past. Following on from that, make sure you have the right pressures in them!
Furthermore, make sure suspension bushes are not perished and splitting. Service your vehicle regularly with a semi synthetic oil.
Hopefully you found this helpful, I will hopefully add pictures in the future when I am back home.
To begin with, the most effective way to add soundproofing to your vehicle is with two layers. A thin, hard layer and on top of that a soft, closed cell foam. You don't want open cell foam as it will only absorb water. The reason behind the different layers is to absorb different frequencies of sound. Another way in which the harder mat type surface will reduce sound is by increasing the mass of the panel it is adhered to, subsequently reducing vibration and thus noise.
When soundproofing my 90, the first areas I targeted was the front foot wells, gearbox tunnel and the removable panels under the seat bases. As a matter of personal choice, on top of the hard sound proofing in the foot wells, I added sound proofing carpet. I got a large quantity at a good price from Noisekiller at one of the LRO shows. I added closed cell foam under the gearbox tunnel interior cover (the black matting). I also applied the hard mat and foam on top of the under seat panels.
Once finished in these areas, I took the vehicle for a drive and there was a noticeable improvement. I didn't have to raise my voice so high to speak to passengers and the general driving experience was improved.
Happy with the result, I took to soundproofing many other areas of the Land Rover. This began with the rear wheel arches. When I purchased the vehicle it already had some hard adhesive mat down identical to the other stuff I had used so I simply applied some of the acoustic carpet over the top of this. In addition, I purchased a second, thinner rubber mat to lay over the original in the back. The combination of the carpet and the chequer plate style mat made the rear of the vehicle look very smart indeed. The results were also noticeable but not to the extent of the changes made to the front. The floor itself in my vehicle is not carpeted so that it is still easy to clean out if it gets muddy. Instead I have thin rubber floor mats with a harder wearing plastic one on top.
I then moved on to applying the carpet to the ceiling inside the vehicle as I only had a headliner in the front section of the vehicle. Again, this made great improvements to the feel of the inside of the vehicle however no real improvement in sound dampening. Although, I did notice the vehicle seemed to retain heat better in the cold.
The final steps I took to reducing sound in the vehicle were to add sound insulation to the doors and the under bonnet area. Although the doors sound more solid when they close, I unfortunately did not notice much of a reduction in noise which was surprising given the thickness of the foam I used in the engine bay (note this was a foam with a heat reflective surface specifically designed for engine bays).
If the material you are using is not self adhesive, I urge you to use a high temperature spray glue or the material you have applied will likely peel away if the panel is left subject to strong sunlight!
So as a result, I can now talk with a slightly raised voice in a Land Rover 90 with a straight through exhaust system at 60+ on the motorway opposed to bordering on shouting in the 90 when it had no sound proofing and a standard exhaust system! I am sure with a silencer fitted my Landy would be even quieter inside. To be fair, I can barely tell there is a straight pipe unless I open the window... Just need to sort that vibrating exhaust bracket.
Other things you can do to decrease the cab noise of your Defender include:
Choosing better tyres (they don't necessarily have to be road tyres, I have Cooper Discover STT mud terrains and I can hardly notice them) Retreads are often noisy, I have had them in the past. Following on from that, make sure you have the right pressures in them!
Furthermore, make sure suspension bushes are not perished and splitting. Service your vehicle regularly with a semi synthetic oil.
Hopefully you found this helpful, I will hopefully add pictures in the future when I am back home.
