bretti_kivi
03-04-2008, 10:48 PM
Anyone done this? anyone interested in playing guinea pig?
I had a quick call with them this afternoon (and will call back tomorrow as the promised callback never materialised) about their double-barrier. I'd like a 10dB drop (so that's half the volume) - there's no point trying for more as the glass will become the limiting factor.
I've now seriously damped my doors, removed the bitumen that was in there, added several Butyl mats per door and will add some more EPDM / closed cell shortly. They also now have noxudol on the aluminium inner skin, which means it no longer goes "clong", but "dum". All the doors do. There's no panel now on the outside of the car that rings when you tap it: it's all "thum".
The inside of the door cards will get another layer of felt; it's the floor and main bulkhead that's causing me grief. The problem lies in the fact that Aluminium simply transmits sound as well as steel, and weighing less, it damps less. So we have to add mass to kill the vibrations. What's getting me at the moment is the road noise.
So, I'm trying a multi-pronged idea. If I can get 5mm EPDM / Vinyl here, then I'll try that. Noisekiller is cheaper and I'd be interested in asking them to create a kit for the A2, also to help damp the tractor properties of the TDI. Which would make it easier for everyone else, too. It mostly is tyre noise, too, as driving on snow drops the noise floor considerably. Removing the rear luggage area side panels increases the noise to silly levels, so i'm rethinking my plan to replace those.
Interest from anyone? Has anyone else got any better ideas?
Bret
I had a quick call with them this afternoon (and will call back tomorrow as the promised callback never materialised) about their double-barrier. I'd like a 10dB drop (so that's half the volume) - there's no point trying for more as the glass will become the limiting factor.
I've now seriously damped my doors, removed the bitumen that was in there, added several Butyl mats per door and will add some more EPDM / closed cell shortly. They also now have noxudol on the aluminium inner skin, which means it no longer goes "clong", but "dum". All the doors do. There's no panel now on the outside of the car that rings when you tap it: it's all "thum".
The inside of the door cards will get another layer of felt; it's the floor and main bulkhead that's causing me grief. The problem lies in the fact that Aluminium simply transmits sound as well as steel, and weighing less, it damps less. So we have to add mass to kill the vibrations. What's getting me at the moment is the road noise.
So, I'm trying a multi-pronged idea. If I can get 5mm EPDM / Vinyl here, then I'll try that. Noisekiller is cheaper and I'd be interested in asking them to create a kit for the A2, also to help damp the tractor properties of the TDI. Which would make it easier for everyone else, too. It mostly is tyre noise, too, as driving on snow drops the noise floor considerably. Removing the rear luggage area side panels increases the noise to silly levels, so i'm rethinking my plan to replace those.
Interest from anyone? Has anyone else got any better ideas?
Bret