Hear the results for yourself -
All the numbers are great but there is no substitute for actually hearing
the difference for yourself. This page will give you two
well-documented examples of how we outperform our competitors. For
the technically minded, we provide a frequency analysis so that you can
see as well as hear. For those who are not, simply push the buttons
and listen. (Use the "back" then "forward" button on the browser to mute
the sound).
What you need to play this example -
The
higher the quality of your speakers and sound card the clearer the tonal
differences will be. However, even playing these sounds on the most
basic system will be revealing. For ease of use, the recordings have been
embedded in a Flash file. If you do not have the Flash Player you
will need to download and install it before you can proceed.
What you will hear -
These recordings compare the performance of three acoustic insulations to
the sound generated by the engine running in open air (i.e. no enclosure).
The sounds were recorded using the same equipment and settings and have
not been modified. The source of the noise is a 3-cylinder Perkins
103-07 diesel engine running at 2,800 rpms. The insulations were all
mounted inside the same enclosure (16 gage SS construction, fully gasketed
using neoprene seals on all surfaces) The products used in the test were:
West Marine Engine Room Soundproofing
#216866 (1.0" thickness. 1.1 Lbs/Ft.2)
Four separate recordings were made and the
results of each of the three insulations were graphed against that of the
insulated box recording. The sound level you will hear accurately
reflects the relative amount of attenuation between the products.
Things to watch and listen for -
Even relatively poor quality composite materials mounted in a
well-designed enclosure will provide substantial sound attenuation.
Therefore you will want to adjust your speakers before switching to the
un-insulated engine recording.
While the audio recordings speak for
themselves, the more technically minded will find the spectral analysis
interesting as well.
You will notice that all of the products perform equally well at
frequencies above 2.5 khz. These higher frequencies are much easier
to attenuate than are the lower tones. Unfortunately, little
of the machinery found on marine vessels produces its primary and loudest
frequencies above 2.5 khz. By comparing the charts of Soundown and
West Marine, you can see how increased thickness of the foam layers and
greater density in the vinyl damping layer are used to address the
challenge of the lower frequencies. The result is an effective,
though large and heavy composite material. By using materials in a
completely different way, BARRIER Ultra-dB achieves better low frequency
attenuation with substantially reduced weight and thickness.
