Dynamat Soundproofing Project - Page 2

4MacFam · 06-05-2013, 05:39 AM

Nice dynamat job!

My build is in progress right now. I delivered the van from quadvan to smb with a stop at home for 2 weeks. I added some dynamat to the side walls in places and on the floor. I pulled the door panels and replaced the speakers and left the panels off when I delivered it. When I gave smb the door switch for the rear door they said that they just tuck it into the door and cover it up with the door panel they install. Said they did it because most people use door lock remotes. I asked to have it put in the panel as I sometimes just carry a key with my vehicles. They put it in the door panel on my build.

Edit: My build @ SMB North

BrianW · 06-05-2013, 10:20 AM

Quote:

Originally Posted by 4MacFam

Nice dynamat job!

When I gave smb the door switch for the rear door they said that they just tuck it into the door and cover it up with the door panel they install. Said they did it because most people use door lock remotes.

Huh, I'd believe that, except for the fact that they did it on mine and my van doesn't have keyless entry/remotes. Are you working with SMB Indiana?

Wanderluster · 06-06-2013, 12:33 PM

Quote:

Originally Posted by Ocsmb

Nice work and write up.

How many man/woman hours do you have in there?

We did it in the evenings and I did not keep track but I would say that it could be accomplished in a weekend if you knew your way around tools and the vehicle. Maybe a bit longer.

Wanderluster · 06-06-2013, 12:54 PM

OK, the numbers are in. Did the sound readings yesterday and as expected I am quite pleased with the results. Because there are so many different types of noise, conditions and phases of driving and for simplicity I am going to average them out to a 15%+ reduction in DB. This might not sound like much but it is. Again that’s the average. I have some phases of driving where the levels are even much lower. The new readings are now for the most part the same as the readings in my 2003 Yukon XL which is a pretty nice ride. I believe that had I had even more access to the engine compartment (i.e. engine pulled, etc) or upper firewall this thing would be dead quiet. I took it on a trip after the readings and drove it about 200 miles and I could not be happier.

Below are the pictures of the power door switch that I found “tucked” inside the rear door and my subsequent install in the door. For those of you that have asked, yes this was an Indiana build, 2004. I decided to install it where I did as I did not want somebody in the bed to accidentally activate the switch open or locked. This location keeps the switch below the bed level (RB50) but allows one on the bed to easily reach down and use it.

geoffff · 06-06-2013, 03:31 PM

Quote:

Originally Posted by Wanderluster

for simplicity I am going to average them out to a 15%+ reduction in DB. This might not sound like much but it is.

It's not quite kosher to apply percentages to dB; it's the difference in dB that matters. But if, for example, you're dropping 12dB from from 82dB to 70dB, that's a *huge* difference. Every drop of 10dB sounds like half as loud as before.

-- Geoff

BrianW · 06-06-2013, 06:54 PM

That's exactly where I mounted my "hidden" rear door power-lock switch. I especially wanted it low enough to not be easily reached if I have my rear tilt-out windows popped open for airflow when parked.

I still don't get why they don't install it. Their "reason" sounds kind of lame. Anybody else out there with an Indiana-built SMB missing your rear door lock switch? Bet it's hidden in there...

larrie · 06-06-2013, 09:54 PM

Quote:

Originally Posted by geoffff

It's not quite kosher to apply percentages to dB; it's the difference in dB that matters. But if, for example, you're dropping 12dB from from 82dB to 70dB, that's a *huge* difference. Every drop of 10dB sounds like half as loud as before.

-- Geoff

I found this Decibel (Loudness) Comparison Chart on the web. It gives examples of noise type and their dB ratings. http://www.gcaudio.com/resources/howtos/loudness.html

Not listed is the average home at 40dB or rustling leaves at 20 dB.

Wanderluster · 06-07-2013, 10:27 AM

Quote:

Originally Posted by geoffff

Quote:

Originally Posted by Wanderluster

for simplicity I am going to average them out to a 15%+ reduction in DB. This might not sound like much but it is.

It's not quite kosher to apply percentages to dB; it's the difference in dB that matters. But if, for example, you're dropping 12dB from from 82dB to 70dB, that's a *huge* difference. Every drop of 10dB sounds like half as loud as before.

-- Geoff

Thanks Geoff...makes sense
I had drops ranging from 8dB to 12dB depending on condition. For instance, idle was 71dB, now it's 63dB. I believe a large portion of my results lay with proper seal of the doghouse and the soundproofing in it's area. I would recommend taking a very close look where the seal should meet metal. Make sure there is NO carpet, padding, wires etc. Remember, there is a turbo less than 2 feet from your right knee. All I know is I am really enjoying what seems like a new ride!

geoffff · 06-07-2013, 10:45 AM

For me, with my gas V10, the sound of my tires on the road surface seems to be the worst offender. Then comes wind noise. The only measurement I've made is with my phone in my lap driving on the highway, where the Decibel app measures somewhere between 75 and 80 dB, depending on road surface. Driving on smooth new asphalt isn't too bad, but old weathered concrete highways where the pebbles start to get exposed out of the cement causes a lot of tire noise. I'd love to drop my interior noise level 10dB so I could hear the stereo better -- or the back seat passengers!

Have you made a similar measurement -- at highway speeds, from the driver seat?

-- Geoff

Wanderluster · 06-07-2013, 11:25 AM

Quote:

Originally Posted by geoffff

For me, with my gas V10, the sound of my tires on the road surface seems to be the worst offender. Then comes wind noise. The only measurement I've made is with my phone in my lap driving on the highway, where the Decibel app measures somewhere between 75 and 80 dB, depending on road surface. Driving on smooth new asphalt isn't too bad, but old weathered concrete highways where the pebbles start to get exposed out of the cement causes a lot of tire noise. I'd love to drop my interior noise level 10dB so I could hear the stereo better -- or the back seat passengers!

Have you made a similar measurement -- at highway speeds, from the driver seat?

-- Geoff

Yes I did and with similar results. My readings wont indicate anything on your ride but that is where the Dynamat Extreme and Dynapad would help a lot with road noise. I did my dB measurements with an iPhone held at ear level in line with drivers head and centered between driver and passenger. I figured the co-pilot would be pissed if I didn't do that the same as we do everything else!

I opted to do this myself as my enjoyment comes from the details and although some stereo shops could do it, I never in a million years would believe that they would do it with the same passion that we would do on an SMB. Probably the hardest part of the project was installing under dash/wheel well/dog house area because you are on your side/back working in tight space and dealing with a lot of wiring and components. I saw this as an opportunity to review what had been done before and to tie-wrap, organize, etc. Well worth it.