But there may never have been a broader range of new technologies in the history of the X family than there is this year.
Callaway today announced nine new products under the new XR moniker, including two drivers, three fairway woods, two hybrids and two irons. The theme consistently across each category seems to be speed. Whether it's the lighter face in the XR drivers or the metalwood-like face cup on the traditionally-shaped, cavity XR irons, Callaway's engineers are chasing new ways for golfers to produce both more ballspeed and, in some cases, more clubhead speed.
But the breadth of offerings (at least two styles in the driver, fairway wood, hybrid and iron offerings) also seems focused on helping individual golfers better dial in the size and shape of head that's going to produce the best results for them.
Evan Gibbs, Callaway's senior manager of product performance in metalwoods, was referring to the new XR fairway woods, but his summary could easily apply to the whole XR family: "We tried to understand where golfers use these clubs, how they use them and how to most effectively design a club for that situation."
All clubs in the XR line are expected to begin to be available in shops by Feb. 20.
XR/XR Pro drivers[#image: /photos/55ad7bf5add713143b42be87]|||xr-driver-back-2015.jpg|||The natural question with Callaway introducing its fourth and fifth drivers since August is how could it be any better. But Callaway is not shy about making its case with the new XR and XR Pro drivers ($350/$400). First, there's a move toward improved aerodynamics. The XR features a pair of distinct speed steps at the front part of the crown designed to reduce drag. It also helps boost swing speed potential through a lighter overall weight (just TK grams on the XR model). According to Gibbs, the lighter weight features draw bias to help average golfers square the face and fight a slice.
Second, the face on the XR is 10 percent lighter, and the center of gravity (CG) is 17 percent lower than last year's X2 Hot. Similar to this fall's Big Bertha Alpha 815 drivers, it utilizes a ribbed structure toward the front of the crown and sole to help increase the area of the face that yields the fastest ball speeds. Third, the XR Pro uses a forged composite crown to produce the lowest CG of any Callaway driver ever.
"The advantage of having forged composite is you can create very aerodynamic shapes, which typically means the crown apex is higher and further aft, without paying a cg penalty," Gibbs says. "You have such a lightweight material that you can pull the crown up and shape it to be aerodynamically efficient without the cg going too high."
Each of the four lofts in the standard model (9, 10.5, 12 and 13HT) and two in the Pro (9, 10.5) include Callaway's eight-way adjustable loft hosel. The hosel allows the user to reduce loft by one degree or increase it by one or two degrees and then also independently alter lie angle. One further benefit of the XR driver is its lighter weight.
__XR/XR Pro fairway woods, hybrids__The distinct shape differences in both the XR fairway wood and hybrid lines grew from how players of different ability levels use the clubs. The fairway wood line includes three varieties (standard, Pro and 3Deep) and the range accommodates 10 lofts, including the only stock 11-wood from a major manufacturer ($230 for the XR, $240 for the XR Pro and XR 3Deep).
The club's primary technology is a redesigned cupface that's thinner and lighter to help boost ballspeeds and lower the CG. The internal weighting updates the wave-like feature toward the front of the sole, pushing more weight forward while still freeing up the area low on the face. This helps to reduce spin and improve ballspeeds for shots hit low on the face.
The XR and XR Pro hybrids offer similar differences to the fairway woods in size and shape (the Pro is decidedly more compact to appeal to better players), and the cupface and low CG design have been updated. Gibbs says the CG on the XR is 46 percent lower than the X2 Hot, while the CG on the XR Pro is the lowest ever for a Callaway hybrid.
Callaway's effort with the XR iron line is to incorporate the flexibility in the face produced by its cup face design but wrap the technology in a more traditional, cavity-back iron shape. Both the XR and XR Pro feature a two-piece construction where the face cup wraps over the entire perimeter of the face and is fused to the sole and back of the iron. This allows for more control of how thin the face can be made to improve rebound across a greater area.
"The benefits of the 360 face cup that we see in an iron are very similar to what we see in a fairway wood or a hybrid," said Luke Williams, senior director of product strategy in fitting and irons.
Within the cavity is an internal wave-like structure that improves performance on low-face impacts and lowers the center of gravity. The XR ($800) features more offset, while the XR Pro ($900) uses a thinner top line and narrower sole.