Sound Reduction
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Sound Reduction Technology ake a ride on an Ellis boat and you will immediately appreciate the extensive engineering we have performed to reduce engine and vibration noise. Our unique suspended oor design, in conjunction with soft engine mounts, high density sound absorption materials, custom exhaust system, ve blade propeller and numerous other sound dampening technologies are combined to create yachts that are among the quietest available today! Sound can be quantied using a meter that measures decibels (dB) {usually on the “A” scale - dB(A)}. The smallest difference in noise level that most humans can perceive is 2 dB, while 100 represents the threshold of pain. Decibels are measured on a logarithmic scale, so an increase of ten decibels equate to a tenfold change. In other words, 100 dB is ten times louder than 90 and one hundred times louder than 80 (10 x 10). Keep that difference in mind when you compare boats. An apparently small difference, say 75 dB compared to 85, can make a huge difference. Sounds perceived by the human ear range from zero on the decibel scale (the quietest sound the human ear can detect) to about 120 dB, where the noise is so intense that it becomes painful. One of the most important things you will need to remember about the decibel scale is that when the sound level increases 10 dB, the perceived “loudness” of the sound doubles. So an increase of just a few “dBs” represents a rather large change in the perceived loudness of the sound. An exposed running boat engine will produce about 100 dB. If you put a simple enclosure around the boat engine, the dB level would drop from 100 to 90. All modern yachts have some level of sound insulation around the engine compartment. With reasonable effort a boat builder can reduce the sound level to the mid 80’s. At Ellis Boat Company we go well beyond the common practice, and the effectiveness of our approach can be seen in the results: an Ellis 36 produces only 75 dB at seventeen knots. Compared to a boat with a sound level of 85 dB, your ear would perceive that boat to be twice as loud as an Ellis 36. In addition, noise occurs at different frequency levels, and an acceptable dB level for one frequency might be unacceptable at another. Some low frequency sounds, such as that emitted by a mufer, can be felt as well as heard. For this reason, we insulate such components from the hull to minimize vibration and noise transmission. Ellis utilizes several noise reductions products and techniques to build some of the quietest vessels available. Our sound insulation gives maximum noise reduction. The smoother, quieter ride of an Ellis boat produces less fatigue. At 75 dB you can have a normal conversation in the main cabin while at cruising speed. And with a trend toward quieter boats, the extra attention to noise reduction that goes into an Ellis will payoff with a higher resale value. But don’t take our word for it, come take a ride on an Ellis and see, hear and feel the difference for yourself! Ellis Boat Company, Inc. • 265 Seawall Road • Southwest Harbor, ME 04679 Phone: 207-244-9221 • Fax: 207-244-9222 • www.ellisboat.com © 2003-2006, Ellis Boat Company, Inc.

Ellis 36 Express Cruiser Performance Data 900 CRUISE SPEED DECIBELS (using “A-scale”) Ellis Boat Company, Inc. • 265 Seawall Road • Southwest Harbor, ME 04679 Phone: 207-244-9221 • Fax: 207-244-9222 • www.ellisboat.com © 2003-2006, Ellis Boat Company, Inc.