| Author |
Message |
vern rainville (68.9.0.180)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 20, 2004 - 5:27 pm: | |
I tryed this on the MAK board and only got a couple of responses.Maybe since it will remain "on top" for a longer period of time, I'll get a few more resonses. I am wondering if the lead sheets should be 1. facing the engine,2. or facing the floor covering, or 3. sandwiched in the middle some where. I will have aluminum sheets facing the engine under the bus frame and 1 1/2" ridgid insulation (which is the same thickness as my bus frame)regardless of how I try to deaden the sound.Any ideas or other ways to achieve "less engine noise" inside the coach? Is the aluminum (or lead) sufficient to reflect heat? Vern (in RI) |
Gary McFarland (Gearheadgary) (68.250.2.76)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 20, 2004 - 5:37 pm: | |
I have about an acre of the stuff in the engineroom of my boat.
there is a silver Mylar layer, foam layer, a wafer of lead, and another thin layer of foam.
In the case of my engine room, the mylar faces the engine.
Gary |
Marc Bourget (209.142.38.81)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, September 21, 2004 - 12:53 am: | |
Vern,
I, like a bunch of others am not posting on the MAK BB anymore. Could be the reason you didn't get an answer. Welcome to the busnuts.
Your question is answered by understanding how sound attentuation or absorbtion works. Simply put, sound is wave energy that you want to either contain or dissipate by converting it to another less disturbing form.
The sandwich technique wants to put an elastic material between the sound source and it's enclosure. The elastic will vibrate from or because the sound waves strike the lead and make it move. The movement of the lead is translated to the elastic which heats up, absorbing the sound energy and producing heat. We don't "hear" heat at these temperatures well, if at all.
The thickness of the elastic layer, in conjuction with the lead used will determine the optimum asborbtion frequency.
So the answer to your question is a qualified "3"
Onward and Upward
Marc Bourget |
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