[tcb] Re: Sound Dampening A Bus

  • From: "w.wood" <evil.scientist.boo@xxxxxxxxx>
  • To: tcb@xxxxxxxxxxxxx
  • Date: Mon, 11 Apr 2011 23:14:23 -0400

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

Other related posts: