Date: Thu, 21 Oct 2004 21:25:25 -0400
Reply-To: tmiller <tmiller@VCMAILS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: tmiller <tmiller@VCMAILS.COM>
Subject: Re: noise reduction
In-Reply-To: <20041019051611.91383.qmail@web13601.mail.yahoo.com>
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Why don't you use a noise cancelling system? Measure the frequency of
the noise, and run it through your stereo amplifier phase shifted 180
degrees? You might even be able to make it automatically adjustable
based on MPH.<br>
<br>
Reinhard Vehring wrote:<br>
<blockquote type="cite"
cite="mid20041019051611.91383.qmail@web13601.mail.yahoo.com">
<pre wrap="">Joel,
thanks for your response. I use "Brown Bread". It is
much less expensive than Dynamat and equally effective
in keeping panels from vibrating. And insulating the
whole right side of my Westy made a difference,
subjectively. Feels more solid. Big difference in how
the sliding door sounds now, when I close it. But,
surprise, the noise level at highway speed didn't
change measurably, the meter doesn't lie. Damping the
panels only takes care of a narrow frequency range
were the panels can resonate. It helps to avoid
rattles and reduces unwanted resonances in the mid and
bass range. But it did not take care of the noise
problem as much as I wanted to believe it after that
much work. I also tried sound absorbers or barriers. I
put carpet on the panels, which absorbs some higher
frequencies, and put open cell foam behind the panels,
which is a reasonable sound barrier / absorber. Stereo
sounds cleaner but still no significant improvement on
noise. Maybe the only way to reduce the noise is to
generate less? Softer / different suspension, replace
worn bearings maybe? Tires with different tread
pattern, maybe 15" rims with wider tires at lower
pressure? Basically after my mildly successful
insulating attempts I'd like to get a feel for how
much improvement I can achieve before I spend the big
$
So how noisy is your ride?
Reinhard, 83 Westy, "Moose"
--- Joel Walker <a class="moz-txt-link-rfc2396E" href="mailto:jwalker17@earthlink.net"><jwalker17@earthlink.net></a> wrote:
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<pre wrap="">need to find a way to reduce the noise. 80 dBA is
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<pre wrap="">just
</pre>
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<pre wrap="">too much. BTW I already know that the best way of
reducing road noise is to slow down :-) Actually
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<pre wrap="">best
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<pre wrap="">is not to move at all.
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<pre wrap="">you can cut down a lot of 'road noise' by putting
some Silencer Strips
(by 3M) or some Rubberized Undercoating by 3M inside
the doors and
behind the interior panels inside.
spray the inside surface of the large flat panels of
the bus's walls.
those panels can drum significantly. i did this on
an 88 and it really
was amazing the difference it made.
you can also do it under the floor in the front,
beneath the
driver/passenger feet. and any other flat panels you
can get to.
anything to stop vibrations getting to/through that
panel. dynamat is
another brand like the 3M stuff.
good luck!
joel
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