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CMI Industrial is proud of its heritage as a designer and manufacturer of top-quality sound and noise attenuation systems that have set the benchmark for quality and innovation. CMI has enjoyed a decades-long leadership position by offering unparalleled products and services, and maintaining industry-leading customer satisfaction.

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CMI Liquid Sound -- A Sound Choice for Performance Boaters

CMI Liquid Sound Muffler

CMI Liquid Sound Muffler - Transom View

Revolutionary sound suppression system reduces sound emissions to unheard of levels.

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NEENAH, WI -- February 15, 2005 -- Custom Marine Inc (CMI) announced it will introduce a revolutionary new exhaust sound suppression system designed to dampen exhaust noise emissions on all inboard and stern drive powered recreational and performance boats during the Miami International Boat Show, to be held February 17-21. This innovative system, Liquid Sound™, will lower exhaust sound emissions to as low as 79 decibels (dB) on most high performance boats -- a sound level nearing that which represents normal household appliances -- without robbing horsepower from the engine.

"We spent nearly two years of research and development time to develop a revolutionary sound suppression system that would meet regulatory requirements without inhibiting the power recreational and performance-oriented boaters demand from their marine propulsion system," said Joe Zelinski, founder and president of CMI. "Our initial decibel target for this project was to achieve a level of sound that was below the most common sound regulation, which is 86 dB. With Liquid Sound, we have exceeded our own expectations.

"Liquid Sound can be applied to any inboard or stern drive exhaust system," Zelinski added, "With Liquid Sound, recreational and performance boaters alike will experience much lower sound decibel levels from their exhaust system -- as much as nearly 25 percent less than sound levels common with many straight-pipe systems -- making their overall on-water experience more enjoyable."

The CMI Liquid Sound system reduces noise by directing exhaust gasses through a high-tech chamber filled with water, which eliminates a direct path for sound waves to travel. This design allows an unrestricted flow of exhaust gas to pass through the chamber without creating the power-robbing backpressure common to most muffler designs. CMI will offer Liquid Sound in both In-Water and Above-Water configurations to meet any marine engine application.

The Liquid Sound, In-Water model provides a sleek and stylized look and is designed to be mounted directly to the outer transom wall. This model directs exhaust gasses to a port located below the surface of the water, which muffles sound while operating at idle or low speeds in close-quarter areas like marinas or other high traffic areas. Away from shore and on-plane, the system allows the open exhaust sound that many performance enthusiasts demand.

The Liquid Sound, Above-Water model is similar in design to the In-Water model; however it provides full-time sound suppression during operation. This model can be mounted on the outside transom wall or inside the engine compartment if room allows. This system will be a popular choice for recreational boating applications where the boat is operated near more populated areas or where regulations demand full-time noise suppression.

According to Zelinski, most inboard and stern drive powered boats reach exhaust noise emission levels in the range of 90 -- 105 dB, which exceeds most local enforcement agency limits for boats operating on waterways 50-feet or less from shore. Noise is measured in decibels, which range from 0 -- the least perceptible sound to the human ear -- to a maximum of 180 dB. The threshold for pain is near 120 dB, or about the level of sound for most rock band concerts. Average city traffic is 80 dB, while normal conversation is approximately 50 dB. More importantly, every increase of 10 dB measured is considered to double the sound level (i.e. 90 dB is twice as loud as 80 dB). Liquid Sound reduces exhaust emission sound to as low as 79 dB.

About CMI

Custom Marine is an industry-leading manufacturer and marketer of OEM and aftermarket exhaust headers, exhaust systems and components designed for any recreational and high-performance marine application. CMI's combination of engineering, manufacturing and design excellence allow the company to deliver products that offer the superior quality, performance and stunning good looks every performance-minded boater demands.

Media Contact:

Chris Morth
Custom Marine Inc.