Tennis Industry magazine


Playtest: Head FXP Power 16

By Greg Raven

FXP Power is a new multifilament designed to build on the success of Head’s recently introduced FXP string technology. In the past two quarters (Q4 2005 and Q1 2006), FXP has been number 15 on the best-sellers list in the Tennis Industry Association/Sports Marketing Survey. According to Head, FXP Power is designed to offer the same superior qualities as FXP in a more powerful string.

Head FXP Power

FXP and FXP Power in turn draw on Head’s well-established FiberGEL technology. (See the playtest report for Head FiberGel in the September 2002 issue of Racquet Tech magazine, and the playtest report for Head FiberGel Power in the January 2004 issue.) FXP Power starts off with a multifilament core of polyamide 66, Around this core is a wrap of polyamide 6 monofilaments, each of which contains an integrated “tri-cluster” of gel fibers (instead of the polyester integrated into the FXP outer wrap). This wrap lends FXP Power elasticity for comfort and power, without sacrificing control. Finally, the string’s outer layer is a DuPont Synthetic 6 pearl coating for durability.

Head FXP Power

The result according to Head is an easy-to-install string for the player looking for a softer string with a lot of power.

FXP Power is available in 16 and 17 in natural only. It is priced from $12.00 per set of 40 feet. For more information or to order, contact Head at (800) 289-7366, or visit

In the lab

We tested the 16-gauge FXP Power. The coil measured 40 feet 7 inches. The diameter measured 1.25-1.26 mm prior to stringing, and 1.20-1.23 mm after stringing. We recorded a stringbed stiffness of 75 RDC units immediately after stringing at 60 pounds in a Wilson Pro Staff 6.1 95 (16×18 pattern) on a constant pull machine.

After 24 hours (no playing), stringbed stiffness measured 70 RDC units, representing a 7 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. FXP Power added 14 grams to the weight of our unstrung frame.

The string was tested for five weeks by 30 USRSA playtesters, with NTRP ratings from 3.5 to 6.5. These are blind tests, with playtesters receiving unmarked strings in unmarked packages. The average number of hours playtested was 20.7.

Our playtest team found FXP Power easy to string, which is not surprising considering the other Head strings that share this general configuration have each rated highly in this category. It has a nice feel, and although fairly soft, blocked holes are no problem. It has virtually no coil memory. Twenty-eight of our 30 playtesters reported that FXP Power is at least as easy to install as other strings.

No playtester broke his sample during stringing, none reported problems with coil memory, one reported problems tying knots, and one reported friction burn.

On the court

Our playtest team found Head FXP Power exhibits above-average performance across the board. The team particularly liked the Playability, which they rated as well above average, with strong scores for Durability, Power, Control, Touch/Feel, Comfort, Spin Potential, Tension Holding, and Resistance to Movement. These scores give Head FXP Power a solid above-average overall rating.

Four playtesters broke the sample during play, one at four hours, two at eight hours, and one at 22 hours.


With FXP Power, Head continues showing its ability to deliver “do-it-all” strings that are carefully targeted toward large segments of the tennis-playing public. But where FXP is aimed toward players needing more control and durability from a string, FXP Power is aimed toward players needing more power and comfort. Each string, however, is very “balanced” in terms of delivering strong results in each of our testing categories, with FXP Power having the edge in Playability. (See the Head FXP 16 playtest report in the August 2005 RSI magazine for comparison.)

Judging by the response we received from our playtesters, Head FXP Power could be — along with FXP — another great “go-to” product for stringers with customers who want a quality product that won’t let them down. And, as good as it is for your customers, its ease of installation will make it just as good for you.


“This is a good string, and I would recommend it. It has a solid feel and lots of baseline power. Needs a dampener. Great serving string. I still have it in my racquet.” 4.5 male baseliner with heavy spin using Head i.X3 MP strung at 58 pounds CP (Tecnifibre NRG2 16)

“This string was the easiest to string that I’ve ever used. Very easy to work with.” 3.5 male all court player using Head i S9 OS strung at 58 pounds CP (Kirschbaum Super Smash 16)

“I’m quite surprised. I do say I love this one. I could easily switch to this compared to the hybrid, though I’d like to try a thinner gauge. It’s amazing how good multifilament strings have gotten. Depending on price and availability of 17 gauge, I’ll switch.” 5.0 male all court player using Head Flexpoint Radical Tour strung at 55 pounds CP (Luxilon Alu Power/gut 16L/17)

“Strung it up and went right to a doubles match. Played great, pin-point accuracy.” 5.0 male serve-and-volleyer using Wilson n4 strung at 57 pounds LO (Poly 16)

“Great string. No break-in required! My friends were asking where my new power and control came from. When I told them it was the string, they wanted their racquets strung with it too.” 3.5 male all court player using Prince Shark DB strung at 58 pounds LO (Babolat Conquest 16)

“I normally play with aramid hybrids or polyester. This string surprised me with its excellent spin potential and playability. It exhibited excellent durability with no string movement — which is why I play mostly with polyesters.” 4.5 male using Prince Triple Threat Graphite MP strung at 62 pounds CP (Luxilon Big Banger Original 16)

“This is a very good string. It is one of the best strings I’ve ever strung. Almost no coil memory. It is a string that has a very good feel without having a lot of spring. I’d be willing to buy it.” 5.5 male all court player using Wilson Pro Staff Tour 95 strung at 61 pounds CP (Prince Synthetic Gut 16)

“Very nice playing string. Had nice feel, comfort and control. During installation, I thought the string would be stiff feeling. The playability was much better than I thought. Seemed as though the ball stayed on strings longer.” 6.5 male all court player using Wilson nTour strung at 58 pounds CP (Wilson NXT 17)

“The string felt like a polyester and was more durable than my usual string, but didn’t give me the bite I usually get. It felt a little dead, and didn’t have as lively a response as I was hoping for. If the price was lower than the popular polys, I consider recommending it for players seeking durability not feel.” 5.0 male all court player using Prince Airstick B1025 OS strung at 56 pounds LO (Wilson NXT Sensation 16)

“String was smooth and easy to string. I definitely noticed the lack of coil memory. String seemed very lively and I liked the power I was getting of the stringbed. String was also very comfortable and did not send much shock or buzzing up my arm.” 4.0 male all court player using Yonex RDS 001 strung at 57 pounds LO (Klip Scorcher 17)

“I liked the overall playability of this string and the durability surprised me. I expected it to break after a couple weeks. There was very little string movement. This string felt good on my arm. It was not as jarring as my old standby. I’d stock this string and recommend it to my customers.” 3.5 male baseliner with heavy spin using Head Liquidmetal Radical strung at 60 pounds CP (Luxilon Alu Power 16L)

“Very nice string. It has a nice feel, comfort, touch, and power. I will keep this string in my frame until it is no longer serviceable.” 4.0 male baseliner with moderate spin using Pro Kennex Redondo strung at 61 pounds CP (Gamma TNT2 18)

“Enjoyed using this string.” 4.0 female serve-and-volleyer using Head Liquidmetal Instinct strung at 58 pounds LO

“Strings settled quickly with good crispness, power, and touch — minimal loss of tension despite lots of hard play.” 5.0 male all court player using Head Ti S6 strung at 60 pounds LO (Luxilon Big Banger/Tecnifibre 515 Gold 16)

“Didn’t hold tension as well as I would have liked, but it is certainly comfortable.” 5.0 male all court player using Prince Tour Diablo strung at 66 pounds CP (Unique Tourna Poly 18)

“Not a bad string, just played a bit dull. Not a lot of pop and semi-firm, but not harsh by any means. Not much time from fraying to breaking and didn’t move around as much as my typical 17g string.” 4.0 male all court player using Tecnifibre 290 XL strung at 59 pounds CP (Klip Excellerator 17)

“What I liked about this string was that was easy on the arm. However, it was not a very lively string and required more effort to drive the ball through. Perhaps stringing 10 percent lower might help.” 4.5 male all court player using Head i.S2 strung at 60 pounds LO (Babolat Pro Hurricane 17)

“This string feels good but it lacks the good overall feel of my regular string. It is showing signs of breaking soon.” 5.0 male all court player using Head Flexpoint Prestige Mid strung at 58 pounds LO (Head Ultratour 17)

“A good string if you are looking for durability, but a little stiff. This would be a great string if you have trouble with breakage. For playability, I would give it an average score.” 5.0 male serve-and-volleyer using Head Flexpoint Radical Tour strung at 63 pounds LO (Klip Venom 17)

“Good comfort. Touch and feel on drop shots and at the net. The strings started to move a lot and tension dropped quickly. Poor spin potential because of string movement.” 5.0 male all court player using Wilson nSix-One 95 strung at 66 pounds LO (Prince Synthetic Gut w/Duraflex 16)

“I didn’t like the playability of this string during the first few hours of play, but it got better and better. A thinner gauge would probably be better.” 4.0 male baseliner using Yonex RDX 500 MP strung at 65 pounds LO (Gamma TNT 17)

“Not bad, but nothing special. This string was comfortable, but did not have any outstanding qualities.” 5.0 male all court player using Wilson nTour strung at 58 pounds CP (Luxilon Alu Power 16L)

“This string got better with time; however, it is not one of my favorites. The string has great power, but I did not find it to have much comfort or control. Durability is not very good as I played only two hours with it, most of the time teaching beginners and intermediate players. Tension maintenance is pretty good. Overall, I was happy when it finally broke.” 5.0 male all court player using Wilson nPS 95 strung at 64 pounds LO (Gamma TNT Fusion 19)

“There was no problem stringing. In my first two hours of playing with it, I was very happy how it played. There was plenty of power and reasonable control but it didn’t last long. In the second two hours, there was considerable movement of the mains and control suffered. I also found I got very little spin and not much touch as I continued to play — it certainly didn’t get better. Recommend stringing it two or three pounds higher. String is not for me.” 4.5 male all court player using Head Protector strung at pounds LO (Wilson Sensation 16)

“This string felt okay at first but never had much feel. In fact, on colder days it feels like a two-by-four. It was hard with a lot of vibration. The strings were all over the place pretty quickly — and when they broke, it was four mains at once.” 4.5 male all court player using Head Ti Radical strung at 65 pounds LO (Gamma Advantage 15L)

“The string lost four pounds with only four hours of doubles. With additional play and tension loss, the racquet became unplayable, especially against heavy hitters. However, it still played reasonably well against slower pace. Overall, a so-so string, nothing of note to brag about — can’t compete with other strings on the market.” 3.5 male all court player using Wilson PS Surge 5.1 strung at 58 pounds LO (Tecnifibre 515 SPL 17)

(Strings normally used by testers are indicated in parentheses.)


(compared to other strings)
much easier 3
somewhat easier 8
about as easy 16
not quite as easy 2
not nearly as easy 0
(compared to the string played most often)
much better 3
somewhat better 7
about as playable 7
not quite as playable 12
not nearly as playable 1
(compared to other strings of similar gauge)
much better 1
somewhat better 6
about as durable 16
not quite as durable 6
not nearly as durable 1
RATING AVERAGES From 1 to 5 (best)
Playability 3.6
Durability 3.3
Power 3.3
Control 3.3
Comfort 3.3
Touch/Feel 3.2
Spin Potential 3.2
Holding Tension 3.3
Resistance to Movement 3.3

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About the Author

Greg Raven  is an associate editor for Tennis Industry 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, or through Facebook, LinkedIn, and Twitter. He plays tennis three to five days a week, and is turning into an avid cyclist.



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