Here are a few other posts in a few other threads I'm cataloging here:

https://www.brightdropforum.com/thr...coustic-thermal-automotive-insulation-for-van-and-car.176/?post_id=472#post-472

https://www.brightdropforum.com/threads/80-mph-limited.177/?post_id=501#post-501

https://www.brightdropforum.com/thr...threads/bd-600-awd-max-range-first-road-trip-thoughts.191/?post_id=643#post-643

https://www.brightdropforum.com/threads/insulation-and-sound-deadening-materails.230/

 

From my research it seems like Resonix may be the best product.

Sound Deadening Material Independent Testing Data

Wondering which sound deadening actually delivers? This page shares independent test results that show how ResoNix CLD Squares and Mega CLD Squares outperform almost every other product in resonance reduction and price‑for‑performance. See the cold, hard data so you can compare brands with...

resonixsoundsolutions.com

It's also the most expensive of course... but it will be what I go with.

 

From my research it seems like Resonix may be the best product.

Sound Deadening Material Independent Testing Data

Wondering which sound deadening actually delivers? This page shares independent test results that show how ResoNix CLD Squares and Mega CLD Squares outperform almost every other product in resonance reduction and price‑for‑performance. See the cold, hard data so you can compare brands with...

resonixsoundsolutions.com

Does it also insulate or is it just sound? I'm looking to do some insulating in the cab at the same time. Certainly can do one layer on another, but if there's a combined product, cuts down the work by roughly 50%!

 

One issue I'd like to raise here is noise on coarse roads. It is remarkable how much quieter a smooth road can seem just after you've left a coarse one.
I wonder if something on the skid plate would help- kilmat or possibly some ribbed material.
Also, I wonder if each tire could be fenced or walled off near the contact patch. Particularily the rear non turning wheels could have a fence very close. Maybe foam like a camping bedroll mat.

 

I would think that placing sound dampening material around each wheel well would probably do a good job of reducing sound. I think my plan is to do the entire floor and firewall of the vehicle, at least as much as I can reach.

 

Materials such as Thinsulate, flooring, sound deadening materials - Campervan Insulation: Upgrade Your Van Today

 

3M also has a sound-dampening, insulation product. They call it acoustic insulation. Here's the data sheet: https://multimedia.3m.com/mws/media/784669O/3m-thinsulate-acoustic-insulation.pdf

 

I've used the Uxcell stuff in my RV under the floor, inside the wheel wells and engine cover.

https://a.co/d/dpM1cUk

It went from having to scream to my passenger, It's hard to tell if the engine is running. Plus temperature transfer is much reduced.

 

Question: can the kilmat style butyl rubber sound mats be applied to the exterior surfaces? For example, our rear wheel wells are just bare aluminum. I was thinking of spraying the underside with rubber coat and applying sound mat strategically on the inside, but could the underside of the wheel well be completely covered with kilmat? Or would gravel just chew it up? Completely exposed to the tire.

 

Seems like the aluminum foil layer would get quickly chewed up by rocks.
What have all of you done with your rear wheel wells, and what do you recommend?

 

The things which reduce sounds:

• absorption - making sound waves run them self out of energy like foams
• mass - heavy things which are difficult to get to vibrate
• stiffness - same concept as mass

They all work on different wavelength. Foams are great on higher frequencies, and mass is good for lower. And stiffness works across the board.

The most important one:
- Airtightness, one 1/4 hole makes the whole assembly almost useless.

 

Solid info!

I recently sound isolated a second floor in my house. I was trying to reduce noise transmission between the second and first floor. For the low frequency noises the best thing was MLV (mass loaded vinyl) as an underlayment to the wood floor. This stuff is a 1lb per sqft (you can get double that that too). What worked best for the high frequency noises was sealing all gaps. I triple sealed the door between the floors and added a hanging sound blanket.
the sound transmission went from understanding conversations between floors to only hear murmuring (if at all).
All to say: mass and gaps are key for sealing sounds out.

 

Hi All,

I've been watching a few videos of youtubers taking the Grounded Brightdrop out for test drives. All of them have one complaint while driving it...the noise in the cab. Has anyone attempted to quiet the cab?

 

Anyone know how the cab sound compares with other notoriously noisy-cabbed vehicles, such as RVs built using the Chevy Express or Ford E-series Cutaway chassis?

 

Massive Awesome this is the key thanks for sharing!