By Charles Plueddeman
Hear the Hush: Sea Ray 250 SLX With Quiet Ride Technology
The Sea Ray 250 SLX employs proprietary materials to significantly reduce sound levels and increase the feeling of luxury in the cockpit.
Builders of premium runabouts frequently share customers with luxury auto manufacturers—buyers who increasingly expect their boat to offer the same technology, reliability and comfort as their car or truck—and a huge stride towards meeting those expectations is Quiet Ride by Sea Ray. Sea Ray says this package of construction features reduces sound levels 25 to 50 percent depending on boat speed and where sound is measured. I had my first experience with Quiet Ride while testing a Sea Ray 250 SLX, a 26-foot 6-inch (including the broad transom platform) bowrider that certainly qualifies for the premium category. Quiet Ride is also presently offered on the similar Sea Ray 270 SLX and 300 SLX models.
The aim of Quiet Ride is to limit what engineers call NVH (noise, vibration, and harshness) through acoustical forensics – finding and controlling sources of sound – and sound-attenuation materials that deaden sound and vibration at the source. It has been my personal and unscientific observation that the conversion of most runabouts from wood to fiberglass stringers about 15 years ago resulted in a significant increase in NVH that builders have been trying to reverse ever since – wood stringers did a great job damping both engine and hull noise. We are not going back to wood stringers, so Sea Ray conducted a thorough analysis of every possible NVH source and sought solutions. Here’s a quick video that shows some of the thought that went into this technology.
Some of those solutions fall under the category of “proprietary,” including whatever material changes Sea Ray has made to the laminate schedule of the composite hull, deck and liner. One of those secret materials is used as the core of its Tuned Transom. A rigid sound deadening material developed by Omni Composites is said to make a significant contribution to the overall NVH effort. A Sea Ray rep told me that you can thump this stuff with a hammer and is doesn’t bounce back or make much sound; it’s a “dead” material. The transom is typically a big, flat panel that has the potential to vibrate like a drum and radiate harmonics from the engine, drive and prop throughout the boat. The Tuned Transom simply absorbs that energy and converts it into heat, that radiates into the atmosphere.
Other Quiet Ride elements are easier to see, including a layer of special acoustic foam that backs the engine compartment bulkhead; baffles placed in the inwales to prevent engine sound from passing into the cockpit; and thick rubber gaskets placed below hatches to stop rattles. Every little noise source adds to the over-all sound level in the boat, so a successful NVH effort requires attention to detail.
The most obvious and notable difference I can relate from a short demo ride is a complete lack of hull noise. You still hear the wake hissing past but the little thumps and rumbles that we typically take for granted as the sound of the boat passing through the water are absent. In fact, until you experience Quiet Ride, you may not be aware of much of this hull noise. The result is a boat that simply seems more elegant or luxurious. And you can have a normal conversation with a passenger across the way. About all that’s left to hear aside from the wind and wake is the sound of the engine, which in this case is pleasing, at least to my ears. Auto makers have been quieting and tuning engine intake noise for years (silent for a luxury sedan, snarling for a sports car) and Mercury Marine has a huge sound lab it uses to tune the sound of its outboard motors. But that science has yet to be applied to inboard and stern-drive engines because it runs counter to strict US Coast Guard regulations for the design of the intake flame arrestor. So we still get to listen to that big block V8 sucking air.
Quiet Ride is well-applied to the 250 SLX, a big, luxurious runabout that lives at the premium end of the market. It features soft vinyl upholstery, gleaming stainless steel hardware, snazzy top-stitched covers on the port and starboard consoles, squishy snap-in carpeting, and a bow seating area and head compartment bigger than my first New York apartment. The 21-gallon fresh-water transom shower probably works better, too. Mercury SmartCraft instruments and DTS (digital throttle and shift) control are standard at the helm. The arch with integral ski tow and sun top is an option, as is a new swim step that with the push of a button deploys from below the boarding platform to offer a wide perch about six inches below the surface, which could also be a cool place to sit on a really hot day.
A 300-horsepower MerCruiser 350 Mag/Bravo Three powertrain is standard, but I say go for the gusto and option up to the throbbing torque and 380 horsepower of the MerCruiser 8.2 Mag/Bravo III package. You didn’t order your new car with the base engine, did you.
For more information, visit Sea Ray Boats.
|Fuel capacity||75 gal.|
|Water capacity||21 gal.|
|Test data provided by Mercury Marine.|
|Power||Mercruiser 350 MAG with a Bravo III drive, swinging a 22″ propset.|
- Charles Plueddeman is Boats.com's outboard, trailer, and PWC expert. He is a former editor at Boating Magazine and contributor to many national publications since 1986.