Photography by Neil Rabinowitz
There’s more than one reason why the Hampton 650 is so quiet.
People buy different boats for different reasons. Fishermen value speed and a big, unobstructed cockpit, while cruisers place range and seaworthiness at the top of their lists. But what about motoryacht buyers? What are they looking for?
Certainly comfort is a major draw, but not just the kind that derives from large, en suite staterooms with enclosed showers. Experienced boaters—those who spend a lot of time on board and, more importantly, underway—know that you can’t be comfortable if your motoryacht roars like a wind tunnel or shakes like a leaf. That’s why they so highly value silence, or the nearest thing to it.
They will certainly appreciate the Hampton 650 Pilothouse. It’s quiet, as you can see from our test results. I took the sound measurements at the lower helm, and the meter reading was so low that I had to ask the captain to shut off the air conditioning because it was louder than either the engine or the sea. I also took measurements in the midship master stateroom, which is forward of the engine room, and at 1,900 rpm my meter barely hit 70 dB(A).
But the 650’s smoothness was just as impressive, no surprise since vibration and sound are so closely related. Credit goes to the standard Seatorque drive system: a self-contained, oil-filled, shaft-and-thrust-bearing propulsion system that transfers the force generated by the propeller directly to the hull via a rubber mounting.
But lots of boats use Seatorque, including those in Hampton’s own Endurance line, and haven’t felt so smooth. Indeed, I’ve never tested a Seatorque installation that worked as well as this one did. I simply felt no vibration.
That sensation may also have been due to the Caterpillar C12.9s, but I can’t say for sure as I’ve never tested another boat with these motors. The 12.9 became available to builders only last year, and our 650 had the first pair installed in an Asia-built boat. It may also have had something to do with Hampton’s extensive use of Soundown noise-reducing insulation, or the coring that overlays the hull laminate expressly to reduce noise.
It also couldn’t hurt that full-beam fuel tankage separates the engine room from the master. Admittedly this is nothing unusual, although the configuration of the tanks is special: There are two, but each is baffled longitudinally down the middle, and the two inboard compartments are connected via a crossover pipe, so you essentially have three fuel compartments. (A second, larger crossover pipe can be opened during refueling, so that all three can be filled from either side of the boat.) Why this unusual configuration? Mainly to prevent 1,200 gallons of diesel from sloshing about in a seaway, compromising stability.
And the 650 is stable. A combination of Pacific swells and a stabilizer system that had not yet been initialized failed to intimidate our test boat, regardless of which heading I put her on. This is due not just to load management, but also to Howard Apollonio and his split-chine hull. Designed to improve early-planing performance, its main feature is chines that are lower in the water amidships. Apollonio says this reduces resistance at cruising speeds while providing lift at higher speeds. Because the chines are low, they more easily penetrate the water, reducing pounding on rough seas and eliminating chine slap at anchor. (In the 650, the double chines run full length; Hampton uses a variation of this design in its Endurance series, but with the chines ending about two-thirds of the way forward.) Yet another benefit is the lack of any discernable “hump” as the boat gets on plane.
While on the subject of the hull, it’s worth noting that Hampton’s construction philosophy emphasizes strength over weight savings, which results in a noticeable lack of squeaks and groans. The hull is solid FRP reinforced by Kevlar, three layers forward for collision protection and two layers abaft that extend chine to chine. (In the unlikely event that these are breached, there’s a standard crash pump in the engine room valved to draw from either engine.) All cabinets and bulkheads are bonded to the hull and/or superstructure.
All this means that at 85,000 pounds, the 650 is no lightweight, yet her performance doesn’t suffer for it. The 1,000-horsepower CATs generated a top speed in excess of 22 knots, and cruising speeds of 19 knots at 2000 rpm and nearly 15 knots at 1750 rpm.
But peace, quiet, and performance alone are not sufficient to lure today’s motoryacht buyers. Since most spend a lot of time living aboard, a pleasant interior is also important. Décor is a matter of personal taste; that said, I really liked our 650’s combination of lightly stained African cherry and tan upholstery and carpets. The work of Pacific Custom Interiors, it combined with extensive main-deck glass to make an already generously proportioned saloon feel even bigger.
Because the colors are muted, your eye is drawn to the joinery. The prowess of Far Eastern yards in this regard is well known, but Hampton’s woodwork here is exceptional even by that standard. All cabinet and drawer faces feature a lovely diamond pattern that’s not only perfectly executed, but also lacking in color variation. That’s because the yard buys wood in bulk, then mills its own veneers, which at 50 mils are considerably thicker than the norm. It also horizontally shaves the veneers from 4-by-8-foot sheets to produce longer veneers, which explains why you can’t find any seams.
Many builders create corner pieces by bending veneers over soft wood, but being aware that corners typically get the most abuse, Hampton creates all of its corners from solid African cherry. To further ensure durability, all wood gets 14 coats of varnish, which results in a finish that contrasts nicely with the granite countertops. While Hampton is not obsessive about weight savings, it does minimize it where practicable, which explains why what appears to be solid granite is actually quarter-inch veneer over honeycomb.
Because there’s little taper to the hull sides, the impression and reality of spaciousness continues below, where there are three en suite staterooms. The layout is fairly conventional, with the exception of the portside guest head, which is three steps up from the stateroom. Such are the compromises required if you want this much accommodation in an LOA of just over 66 feet.
It’s a small trade-off for a motoryacht that not only sleeps six, but also cossets them. Not only will everyone aboard enjoy comfort and convenience, they’ll also revel in a level of quiet and serenity that results not from one single feature, but a synergy of many.
Generator: 16- and 20-kW Northern Lights
Conditions During Boat Test
Air temperature: 67°F; humidity 65%; seas: 2-4'; wind: 5 knots
Test Boat Specifications
- Test Engine: 2/1,000-hp Caterpillar C12.9 diesel inboards
- Transmission/Ratio: Twin Disc MGX5136-A, 2.52:1 gear ratio
- Props: 38 x 35 5-blade Nibral
- Price as Tested: $2,950,000
This article originally appeared in the February 2017 issue of Power & Motoryacht magazine.