ear plugs. On Mon, Apr 11, 2011 at 10:55 PM, kelly dosch <kellydosch@xxxxxxxxx> wrote: > Thanks for that. I was hoping that doing the floor was the ticket to road > noise reduction. I might even undercoat it. > Genius idea to put the insulation in big freezer bags! (to avoid > moisture retention, I assume) > > --- On *Mon, 4/11/11, David Schwarze <dschwarze@xxxxxxxxxx>* wrote: > > > From: David Schwarze <dschwarze@xxxxxxxxxx> > > Subject: [tcb] Re: Sound Dampening A Bus > To: tcb@xxxxxxxxxxxxx > Date: Monday, April 11, 2011, 10:28 PM > > > I have been experimenting with sound deadening lately out of necessity. > With the old air-cooled motor, the sound of the engine running was somewhat > endearing and only left a slight ringing in my ears after several hours on > the interstate. With the TD engine, it's a whole new, much noisier world. > The unholy racket coming from the engine was unbearable and I'm sure would > have done permanent damage to my hearing on long trips. My sound meter was > registering over 100db in the drivers seat. > > First I filled the cavity behind the rear seat with pillows, blankets, old > clothes, towels, etc. and put two pillows up against the C-pillars. This > did not help much at all. > > Next I covered parts of the walls and floor with Q-pads. I also removed > the paneling, stuffed 1 gallon freezer bags with pink insulation and used > them to fill the cavities, then replaced the paneling. I also put the heavy > rubber floor mat back into the cargo area followed by a layer of carpet jute > and then a layer of carpeting. Those changes resulted in the nice thunk-ing > doors that Kelly mentions and a slight reduction in noise level, but still > way too high. High enough that I was wearing headphones, except that they > didn't work because the noise was a low-frequency drone that went right past > them. > > Next I removed the front transaxle mount and made a new one that uses a lot > more rubber. This made a big difference at highway cruising speed but when > I push the RPMs up to passing speed, it is still way too loud. Fortunately > the noise is tolerable if I hold it to no more than 62mph. Still way louder > than a stock air cooled motor though. > > Finally I had a friend sit in the back of the bus and listen for noisy > spots. Surprisingly, most of the noise was coming from the floor just > behind the bulkheads. There were already Q-pads in this area. I went to > Home Depot and bought 8 bags of topsoil and arranged them strategically to > cover the entire floor. Bingo! I could hear myself think again. I > considered leaving the dirt in there, maybe planting grass as a floor > covering but the 320lbs of added weight was a little excessive. I took out > the dirt and bought a sheet of 3/4" birch plywood which I will attach to the > floor over the Q-pads and under the carpet jute. A guy on another list did > say that the biggest reduction in noise in his bus was when he installed a > hardwood floor so I'm hoping it will come close to the noise reduction of > the topsoil. > > I figure that if I put the stock aircooled engine back in my bus now, I > wouldn't be able to hear it over the wind noise. But I will never know for > sure. > > -David > > On 4/11/2011 1:41 PM, kelly dosch wrote: > > Well I can't tell a difference yet, but I have a lot more work to do. > I need another roll to do the entire floor. I also want to put that silver > foil bubble wrap under the carpet. When the AC is running you can feel a LOT > of heat rising up off the floor. All that will have to wait until after The > Classic. > Just four more days!!!! WEEEEE! Woop! I just piddled a little. > > --- On *Sun, 4/10/11, Cari Smith > <cariandpaul@xxxxxxxxx><http://mc/compose?to=cariandpaul@xxxxxxxxx> > * wrote: > > > From: Cari Smith > <cariandpaul@xxxxxxxxx><http://mc/compose?to=cariandpaul@xxxxxxxxx> > Subject: [tcb] Re: Sound Dampening A Bus > To: tcb@xxxxxxxxxxxxx <http://mc/compose?to=tcb@xxxxxxxxxxxxx> > Date: Sunday, April 10, 2011, 9:11 AM > > Cant wait to hear your road test results > > On Apr 9, 2011 11:57 PM, "kelly dosch" <kellydosch@xxxxxxxxx> wrote: > > So I just bought a roll of sound dampening stuff, started installing > it on my bus and thought I would share my results, in case any of you have > considered it but were not sure if it was worth the trouble. > First, let me just say, it is. Holy crap. > There are a lot of sound deadening products out there, but I just went > with a cheap roll of Window Wrap from the lumber store. Same crap, lower > price. > It is a film of some kind of rubber/tar compound on a foil backing, peel > and stick. Only about 1 millimeter thick and the sales person assured me it > won't melt and run even at the high temps in a parked car. > One $20 roll is enough to do all your doors and rear hatch, over the > engine and maybe under the Z-bench. > All that bare metal in a bus just picks up vibrations and reverberates it > everywhere. This gooey film absorbs and dampens those vibrations. > I was skeptical, but I tried it anyway because I was tired of my doors > sounding like slamming the lid down on a dumpster every time I closed them. > It was making me wince. > Well. Now my door slams shut with a wonderfully satisfying *thunk* and > no tinny reverb. It gives the illusion of solidity and I don't care if it is > illusion or not. It sounds and feels great. > What I really did not expect was the stunning improvement of the sound > quality from my door speakers. > I know this stuff is made to improve your stereo's sound, but I really > did not expect much difference. Surprise! It's like I upgraded my speakers > or something. And I haven't even done the passenger door yet! > I haven't yet tested it on the road so I can't tell how it works on road > noise yet. I still have to do the cargo door, passenger door and under the > seat. > But I can say so far, it was worth it for the muffled satisfying *thunk* > of the driver's door and the improvement in the sound of my music already. > I will eventually be doing the floor under the carpet for sure! > They say a lot of road noise comes from the tranny and to double it up on > the floor between the seats. I can't wait to try it but that will have to > wait until after The VW Classic. > > -- My Email Moniker http://www.findinternettv.com/Video,item,1570570433.aspx