Playtest: Prince Beast XP
By Greg Raven
Prince Beast XP is a brand new monofilament string, which Prince refers to as a precision tuned thermo-poly featuring a secret alloy additive. According to Prince, Beast XP offers advanced performance characteristics not found in conventional polyester strings, including consistent dynamic response over a wide range of tensions and string patterns, providing unsurpassed precision.
According to Prince, it developed Beast XP over a period of two years using high-speed video shot at 5,000 frames per second to determine the optimum properties for a control-producing string. Prince engineers claim to have optimized ball trajectories and maximized ball spin to achieve the ultimate control-producing string. Beast XP withstood rigorous on-court testing from world-class players at the IMG/Bollettieri Academies and elsewhere to confirm the findings in the lab. Two finalists at the 2010 Eddie Herr International Junior Tennis Championships were using Prince Beast XP.
See the Beast teaser video here.
To validate its design methodology, Prince took the innovative step of seeding 20,000 sets to players around the world, outside of normal Prince channels, under the name “361 Nation.” These players reported preferring “361 Nation”/Beast XP over the best name-brand strings from the competition, in terms of providing better control, spin, feel, and tension maintenance.
According to Prince, the target customer for Beast XP is the aggressive player looking for maximum control and spin so he can unleash his power game.
Beast XP is available in 16 gauge (1.30 mm) only in green only (to heighten the identity with Prince), although 15 (1.35 mm) and 17 (1.25 mm) gauges are in the works. It is priced from $15 for sets of 40 feet, and $240 for reels of 720 feet. For more information or to order, contact Prince at 800-2-TENNIS, or visit beastxp.com.
In the lab
The coil measured 40 feet. The diameter measured 1.33-1.35 mm prior to stringing, and 1.29-1.31 mm after stringing. We recorded a stringbed stiffness of 76 RDC units immediately after stringing at 60 pounds in a Wilson Pro Staff 6.1 95 (16 x 18 pattern) on a constant pull machine.
After 24 hours (no playing), stringbed stiffness measured 70 RDC units, representing a 8 percent tension loss. Our control string, Prince Synthetic Gut Original Gold 16, measured 78 RDC units immediately after stringing and 71 RDC units after 24 hours, representing a 9 percent tension loss. In lab testing, Prince Synthetic Gut Original has a stiffness of 217 and a tension loss of 11.67 pounds, while Prince Beast XP 16 has a stiffness of 247 and a tension loss of 17.68 pounds. Beast XP added 17 grams to the weight of our unstrung frame.
The string was tested for five weeks by 36 USRSA playtesters, with NTRP ratings from 3.5 to 6.0. These are blind tests, with playtesters receiving unmarked strings in unmarked packages. Prince recommends stringing Beast XP 1-2 pounds lower than other poly strings, but we instructed our playtesters to string 5-10 percent lower than a typical nylon string. Average number of hours playtested was 19.1.
No playtester broke his sample during stringing, six reported problems with coil memory, one reported problems tying knots, and none reported friction burn.
On the court
Out of the 150 strings we’ve playtested for publication to date, Prince Beast XP finished 8th overall in Resistance to Movement, 16th overall in Durability, and 17th overall in Tension Retention. These rankings give Prince Beast XP a well-above-average overall score.
Three playtesters broke the sample during testing, one at six hours and two at eight hours.
Prince has really made a commitment in the development of Beast XP, from investing years in defining and refining it, to using high-speed cameras to determine exactly how the ball comes off the strings, to surreptitiously rolling out Beast XP as the unknown “361 Nation” against the best and most respected strings from the competition. The effort seems to have paid off already amongst junior players, who must be pleased with the durability of Beast XP, on top of its other qualities.
“This string has great control at lower tensions. Playability and bite remain consistent, despite tension loss. Big baseline strokes are easier to control than soft touch shots.” 4.5 male all-court player using Babolat Pure Drive Roddick strung at 55 pounds CP (Luxilon Original Rough/Babolat Addiction 16/16)
“Remarkable power for a polyester. These strings snap back with force to create a heavy ball.” 3.5 male baseliner with heavy spin using Babolat Pure Drive Cortex strung at 60 pounds CP (Babolat RPM Blast 16)
“Great balance of control and power. The absence of noticeable tension loss is a real plus. Durability is excellent.” 4.0 male baseliner with moderate spin using Wilson K Zen Team strung at 56 pounds LO (Prince Hybrid Power EXP 17/16)
“This poly is softer and more playable than most of the durability strings on the market. It has the kind of responsiveness and power most commonly found in softer materials. The extra pop, spin, and control on my serve and instantly apparent. The hybrid possibilities are endless.” 4.0 male serve-and-volley player using Prince Speedport Pro White MP strung at 57 pounds CP (Wilson Sensation/Prince Synthetic Gut Original 17/18)
“Given the high comfort level, this is destined to become a very popular polyester. This is not just for hard hitting juniors.” 4.5 male serve-and-volley player using Head Youtek Extreme MP strung at 58 pounds CP (Gamma Professional 17)
“I have never experienced a polyester with such remarkable tension maintenance. Power and control are also above par. With a thinner gauge and soft cross, sky’s the limit.” 4.5 male all-court player using Dunlop Aerogel 4D 3 Hundred strung at 57 pounds CP (Tecnifibre Pro Red Code/Gamma Synthetic Gut 18/16)
“This is a very comfortable polyester with excellent control and spin.” 5.0 male all-court player using Wilson BLX Tour strung at 50 pounds CP (Babolat VS Team 17)
“Phenomenal control and durability. The firm feel provides excellent feedback, resulting in accurate placement. People who like to take big swings will love this string!” 4.0 male baseliner with heavy spin using Dunlop Aerogel 4D 5 Hundred Tour strung at 58 pounds LO (Solinco Tour Bite 16L)
“This string has controllable power. The surprisingly good feel and playability make touch shots a breeze, especially at net where polyester sometimes plays too dead. Comfort and control are present from the very first hit.” 4.5 male all-court player using Wilson Hyper Hammer 5.3 Stretch MP strung at 53 pounds CP (Gamma Zo Tour Rough 16)
“Tie me to the mast! The siren song of heavy spin, resistance movement, and durability is calling me away from my current set up.” 4.5 male all-court player using Wilson nTour strung at 52 pounds CP (Multifilament Nylon/Monofilament Polyester 16/16)
“Good power and spin on serves. Excellent resistance to movement. Depth control is outstanding. Feel is slightly lacking.” 4.5 male all-court player using Wilson K Six One Tour strung at 58 pounds CP (Gosen OG Sheep Micro 16)
“This string increased both my ace and double fault percentages. The durability and resistance to movement are excellent.” 5.0 male all-court player using Babolat Drive Z Cortex strung at 58 pounds CP (Luxilon Original 16)
“Outstanding control and power. If a thinner gauge is available, this could be my new string.” 5.0 male all-court player using Babolat Pure Drive Cortex GT strung at 57 pounds CP (Luxilon TIMO 18)
“The control and resistance to movement are outstanding. After 19 hours of hard hitting, this string still looks fresh. Feel is lacking, but vibration is minimal.” 4.0 male all-court player using Babolat Pure Drive Roddick + Cortex GT strung at 56 pounds LO (Solinco Tour Bite 17)
“This string is softer than your average polyester. Players who have ‘written-off’ polyester because of the high stiffness are encouraged to take a second look.” 4.0 male baseliner with heavy spin using Babolat Pure Drive Roddick strung at 57 pounds LO (Luxilon Alu Power Fluoro 17)
“This is a user-friendly polyester with exceptional comfort, playability, and control. Tension maintenance is impressive. Durability is my only concern.” 4.5 male all-court player using Head MicroGEL Prestige Pro MP strung at 54 pounds CP (Luxilon Alu Power Rough/Head Ultra Tour 16L/17)
“This string has good touch for a polyester. Power is on the low end. Tension maintenance is excellent. The absence of notching makes for a very durable string.” 5.0 male all-court player using Yonex RDS 002 Tour strung at 54 pounds LO (Babolat VS Touch/Luxilon Alu Power Rough 16/16L)
“Impact feels very solid. Control is excellent. Shows no wear after 30 hours. Lower tensions are advised, especially for players who are not familiar with polyester.” 4.0 male baseliner with heavy spin using Wilson nPro strung at 52 pounds LO (Signum Pro Poly Plasma 18)
“This string feels and plays like a traditional poly. It has great control from all areas of the court.” 4.5 male all-court player using Head Youtek Radical OS strung at 55 pounds LO (Luxilon M2 Plus 16)
“Given how stiff this sting handles during installation, I am surprised by the comfortable feel on court. Tension maintenance is exceptional. Even after many hours of hard hitting, the bite never wavers. A soft cross would allow one to adjust playability to taste.” 4.0 male all-court player using Volkl V1 Classic strung at 54 pounds CP (Head Synthetic Gut PPS 17)
“Pack an extra dampener. The buzzing is high. Control, tension maintenance, and durability are excellent.” 4.5 male baseliner with heavy spin using Babolat AeroPro Drive strung at 64 pounds LO (Babolat Superfine Play 16)
“This an arm friendly polyester with decent touch, feel, and comfort. The control is excellent, especially on volleys. However, with so many great polyesters on the market, this string might have trouble separating itself from the pack.” 3.5 male all-court player using Prince Tour Diablo MP strung at 60 pounds CP (Luxilon Alu Power/Gamma Synthetic Gut 16/16)
“This is lively polyester with good durability.” 5.0 male all-court player using Head MicroGEL Extreme Pro strung at 48 pounds LO (Prince Poly EXP 16)
“The harsh and ‘pingy’ response is easily countered with some well placed lead.” 5.0 male all-court player using Head Flexpoint Radical MP strung at 40 pounds CP (Polyester/Nylon 16)
“As a full poly set-up, this string a tad stiff. I bet it would be great in a hybrid. The tension maintenance, spin, durability and control are excellent.” 4.5 male all-court player using Prince EXO3 Rebel (hole inserts) strung at 57 pounds LO (Solinco Tour Bite/Prince Synthetic Gut Multifilament 18/17)
“On a continuum between ‘great’ and ‘terrible,’ I would put this string just above the middle. It has decent control, spin, and durability.” 4.0 male baseliner with heavy spin using Boris Becker Delta Core Legend strung at 54 pounds CP (Gamma Zo Tour 17)
“This string plays stiff initially, even at lower tensions. Control and spin are adequate, but feel and power are lacking. It is recommended to big hitters in search of control and spin. It broke due to notching.” 5.0 male all-court player using Yonex RDS 002 Tour strung at 48/45.6 pounds CP (Tecnifibre X One Biphase 17)
“This poly has decent control, but it does not really shine in any one area.” 6.0 male all-court player using Wilson BLX Tour strung at 53.5 pounds CP (Wilson NXT 17)
“The playability, spin, and feel are average. I think a thinner gauge would bring out this string’s best qualities.” 4.0 male all-court player using Wilson K Pro Tour strung at 32 pounds CP (Golden Set Hex Poly 17)
“While not as harsh as most of the polyesters I’ve tried, this string will never be confused with a multifilament nylon.” 4.5 male baseliner with heavy spin using Babolat Pure Drive strung at 54 pounds CP (Isospeed Professional 17)
“While the spin is good, poly neophytes will probably want to partner this string with something soft. It’s a little tough on the arm.” 4.0 male serve-and-volley player using Wilson BLX Surge strung at 54 pounds LO (Wilson NXT 16)
“The ball seems to slip off the strings unpredictably. There is not enough feel or feedback to gauge depth. The power level is quite high.” 5.0 male serve-and-volley player using Wilson BLX Six One (76 Holes) strung at 58 pounds LO (Wilson Hollow Core 16)
“This string has great power and control during the first few sessions. After that it plays decidedly average.” 3.5 male all-court player using Wilson K Blade strung at 52 pounds CP (Solinco Tour Bite 17)
“This string is recommended to players who generate their own power. It errs on the side of durability rather than comfort. The ball feels like it’s sliding off the stringbed rather than being ‘gripped’ and rotated.” 5.0 male all-court player using Wilson BLX Pro Tour strung at 52 pounds CP (Wilson Hollow Core Pro 17)
“This string is lifeless and unresponsive. The lack of bite and playability is a deal breaker. The tension maintenance, durability, and color are the only strong suits.” 4.5 male all-court player using Gamma T Seven strung at 56/55 pounds CP (Pacific X Force 17)
“This string has low power and below average bite.” 4.0 male all-court player using Volkl V1 Classic strung at 54 pounds CP (Wilson Hyperlast Spin 17)
(Strings normally used by testers are indicated in parentheses.)
| EASE OF STRINGING
(compared to other strings)
|about as easy||19|
|not quite as easy||8|
|not nearly as easy||2|
| OVERALL PLAYABILITY
(compared to the string played most often)
|about as playable||11|
|not quite as playable||17|
|not nearly as playable||4|
| OVERALL DURABILITY
(compared to other strings of similar gauge)
|about as durable||13|
|not quite as durable||3|
|not nearly as durable||0|
| RATING AVERAGES
From 1 to 5 (best)
|Durability (16th overall)||4.3|
|Holding Tension (17th overall)||3.6|
|Resistance to Movement (8th overall)||4.1|
See all articles by Greg Raven
About the Author
Greg Raven is an associate editor for RSI magazine and technical writer. He is certified as a Master Racquet Technician by the U.S. Racquet Stringers Association. He can be reached via e-mail at firstname.lastname@example.org, or through Facebook, LinkedIn, and Twitter. He plays tennis five days a week, and is turning into an avid cyclist.