Playtest: HEAD Sonic Pro 17/Natural Gut 16
By Greg Raven
Head Sonic Pro 17/Natural Gut 16 is a “do it yourself” hybrid with a twist: It is one of several hybrids pre-matched by the Head Perfect Match Hybrid program. What Head has done is create a matrix showing the features and benefits of using its strings in hybrid configurations, so that each player can choose a combination based on his needs. To select a combination, the player chooses among power, control, durability, and spin for what he wants most from his string, and then among power, control, durability, and touch for his second-most desired characteristic. This makes the Perfect Match Hybrid program both comprehensive and easy to understand and use. The Head strings that make up the Perfect Match matrix are FXP, FXP Power, Sonic Pro, and Natural Gut. (You can see the Perfect Match matrix on page 13 of this issue.)
In this case, the combination is Sonic Pro 17 and Natural Gut 16. The player choosing this hybrid would be looking for durability as the main benefit and the maximum amount of touch for the secondary benefit. The Perfect Match would be Sonic Pro 17 mains (for durability) with Head Natural Gut 16 crosses (for touch).
According to Head, Sonic Pro is made of uniquely refined copolymer polyester and an extra combination of resins and fibers, and it offers superior durability and control for extra pop and spin. USRSA members ranked it the most durable 17-gauge string in the 2008 USRSA Members’ Choice Awards String Survey. See the playtest report on Head Sonic Pro 17 in the July 2007 issue of RSI magazine.
Head tells us that Natural Gut offers the optimum blend of touch, power, comfort, feel, and spin. Created with independent gut fibers bonded together, Head Gut is very resilient. A special coating has also been used to improve durability and stringing.
This combination is priced from $29.75 (half set of Sonic Pro, $6.75; half set of Natural Gut, $23). For more information or to order, contact Head at 800-289-7366, or visit head.com.
In the lab
The coils measured 20 feet for each half set. The diameters measured 1.24-1.25 mm (Sonic Pro) and 1.34-1.35 mm (Natural Gut) before stringing, and 1.21-1.22 mm (Sonic Pro) and 1.29-1.30 mm (Natural Gut) after stringing. We recorded a stringbed stiffness of 80 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 73 RDC units, representing a 9 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. Sonic Pro 17/Natural Gut 16 added 17 grams to the weight of our unstrung frame.
The string was tested for five weeks by 37 USRSA playtesters, with NTRP ratings from 3.0 to 6.0. These are blind tests, with playtesters receiving unmarked strings in unmarked packages. Average number of hours playtested was 24.3.
Hybrids of polyester and natural gut are typically easy to install, and this combination is no different. The stiffer poly is a breeze to put in the mains, and the softer gut slides across the mains without difficulty. Of course, you must exercise the normal care when working with natural gut.
One playtester broke his sample during stringing, nine reported problems with coil memory, two reported problems tying knots, and four reported friction burn.
On the court
Our playtest team found a lot to like in this Head hybrid, ranking it sixth overall in both Power and Control, eighth overall in Playability, and nineteenth overall in Spin Potential. In addition, the team rated Head Sonic Pro 17/Natural Gut 16 well above average for Durability, Touch/Feel, Comfort, Tension Retention, and Resistance to Movement. The combined average places this Head hybrid ninth overall in our 134 published playtests.
Three playtesters broke the sample during the playtest period, two at eight hours and one at 15 hours.
With all due respect to the high marks garnered by the hybrid combination of Head Sonic Pro 17 and Natural Gut 16, in some ways the real breakthrough here is the Head hybrid stringing program itself. The selection matrix is so straightforward it should encourage players to experiment with a hybrid for the first time. And, if you don’t get the ideal setup the first time, the selection matrix guides you in the correct direction.
If you think that this Head hybrid might be for you, pick up set to try. If not, check the matrix and select a different combination based on your requirements.
“This string packs a punch. Volleys have nice pop, making this a real weapon for doubles specialists who like to put the ball away. The gut crosses make for some nice touch shots. This is recommended to players in search of a hybrid with extra power.” 3.5 male all-court player using Volkl Tour 10 MP strung at 59 pounds CP (Gamma TNT2 17)
“Finally, a hybrid that is not too stiff. This string has tons of feel. This is the best hybrid I have ever used.” 5.5 male all-court player using Wilson K Blade strung at 58 pounds LO (Wilson NXT Tour)
“Great feel. This string does everything well. This is not a niche polyester hybrid. It will find a wide audience.” 4.5 female all-court player using Head Flexpoint 4 strung at 56 pounds LO (Prince Synthetic Gut w/Duraflex 16)
“Care must be exercised with the natural gut during installation. This hybrid has very high playability, comfort, feel, and control.” 3.5 female all-court player using Head CrossBow 4 strung at 58 pounds CP (Gamma Asterisk/Gamma Live Wire 16)
“Ideal combination of spin, control, feel, and power. The gut has excellent durability, despite some fraying. Off center hits are a bit harsh. Perhaps reducing the tension of the poly would alleviate this. Pocketing is pronounced, adding to the control. I would not hesitate to recommend this string to a diverse cross section of players.” 4.5 male all-court player using Wilson K Six.One Tour strung at 55 pounds CP (Gosen Polylon/Wilson K Gut 17)
“This hybrid has it all: playability, control, comfort, and tons of bite. The natural gut starts fraying after a few sessions. I would definitely recommend this to my customers.” 4.5 male all-court player using Prince Triple Threat Hornet strung at 62 pounds CP (Wilson NXT 16)
“This is the best hybrid I’ve tried. I’m sold.” 4.0 male all-court player using Prince O3 Hybrid Hornet MP strung at 55 pounds LO (Prince Synthetic Gut Original 18)
“Buttery smooth! Crisp and comfortable. The power is very easy to control, and the playability is top of the line.” 4.0 female all-court player using Prince 03 Speedport White MP strung at 62 pounds CP (Gamma Zo Power 16)
“Very durable, minimal string movement, excellent control, and great feel.” 4.5 female all-court player using Head CrossBow 4 strung at 58 pounds CP (Head Sonic Pro 17)
“I absolutely love this string. The combination of power and control is outstanding. This string adds some kick to my spin serve. I will recommend this to most of my customers.” 3.0 male all-court player using Wilson nBlade strung at 50 pounds CP (Wilson NXT 17)
“Very easy installation. No coil memory. This string is responsive and powerful. It has good control, comfort, and spin.” 4.0 male all-court player using Head MicroGEL Radical MP strung at 55 pounds CP (Kirschbaum Super Smash Spiky 17)
“Great feel. Control comes easy, no matter how big the swing. Power is there when needed.” 3.0 male all-court player using EXO3 Graphite (port inserts) strung at 50/48 pounds CP (Prince Premier LT 17)
“Solid power, touch, spin, and control. This combination strikes a fine balance between playability and durability. After a short break-in, performance improves.” 5.0 male all-court player using Wilson Pro Staff 6.1 strung at 60 pounds LO (Tecnifibre Multifeel 16)
“This is a great overall string. It does everything well. There is a unique combination of feel and durability.” 5.0 male baseliner with moderate spin using Babolat Aero Storm (320 grams) strung at 60 pounds CP (Luxilon Big Banger Alu Timo 18)
“Great control and tension maintenance. For players who prefer a soft feel, I would recommend a 10% tension reduction.” 4.5 male all-court player using Wilson K Zen Team strung at 53 pounds LO (Wilson NXT 16)
“This is recommended to those looking for the control benefits of a poly in a very comfortable package.” 5.0 male all-court player using Wilson K Six.One Tour strung at 58 pounds LO (Wilson NXT/Luxilon Big Banger Alu Power Fluoro 17)
“This hybrid has an excellent balance of durability and playability. I would recommend it to someone who is looking for more power and feel, but does not want the dead, stiff response of a full poly set-up.” 4.0 female all-court player using Head MicroGEL Extreme Team OS strung at 58 pounds CP (Head Sonic Pro 17)
“Great feel and very little string movement. Above average control and power.” 4.5 male baseliner with moderate spin using Head Flexpoint Radical MP strung at 58 pounds LO (Gamma TNT2 17)
“This is a very comfortable hybrid with excellent pop.” 4.0 male baseliner with heavy spin using Head CrossBow 4 strung at 58 pounds CP (Wilson NXT 16)
“After a short break-in period, this hybrid plays with a wonderful combination of control, touch, durability, and power. This would be great for the poly neophyte in search of a comfortable entry point.” 5.0 male all-court player using Prince O3 Speedport Pro White MP strung at 56 pounds LO (Prince Premier LT 17)
“This is a comfortable control string. Touch shots and placement volleys are very easy to execute. Achieving depth requires a little extra effort. There is some noticeable tension loss after 7 hours. My students were impressed!” 4.0 male all-court player using Head i.Radical OS strung at 63 pounds LO (Head Intellitour 17)
“Excellent power on serves, and great touch on volleys. The spin potential is moderate. Very comfortable. Tension loss is noticeable after the first few sessions. Given the soft feel, I think you can get away with “maxing” the tension.” 4.5 male all-court player using Wilson K Five strung at 57 pounds CP (Luxilon M2 Pro 17)
“This is a very playable hybrid. Tension maintenance is excellent.” 4.5 male all-court player using Wilson K Blade strung at 55/59 pounds CP (Gamma Zo Tour 17)
“For a hybrid, the feel is incredible.” 5.5 male all-court player using Wilson K Blade strung at 60 pounds LO (Wilson Sensation 16)
“Excellent combination of durability and power. Great for aggressive baseliners.” 5.5 male serve-and-volley player using Prince Michael Chang OS strung at 63 pounds CP (Prince Sweet Perfection 16)
“This string plays well from the baseline. Great spin and control on serves. Volleys are very crisp. Depth control is excellent. There is enough feel for touch shots. Control suffers after the tension loss.” 4.5 male baseliner with heavy spin using Head MicroGEL Prestige MP strung at 58 pounds CP (Gosen Polylon 17)
“Excellent playability for the first 2 hours. The pocketing and extra dwell time truly enhance control. Over time, however, the string bed loses resilience, and control suffers.” 6.0 male all-court player using Head Protector OS strung at 60 pounds LO (Wilson Sensation 16)
“On slower strokes, the feel is a bit dead. Perhaps a lower tension would liven things up.” 3.0 male all-court player using Slazenger Type 2 NX Two strung at 60 pounds LO (Gamma Asterisk 16)
“Fairly good control, but lacks the ‘wow’ factor.” 5.0 male baseliner with moderate spin using Head MicroGEL Radical Team MP strung at 56 pounds LO (Gosen OG-Sheep Micro 16)
“Nice feel and plenty of power. After a week, however, the honeymoon ended and I was longing for a full poly setup. Maybe a higher tension would preserve the crisp feel longer.” 5.0 male all-court player using Head MicroGEL Monster strung at 60 pounds LO (Head Sonic Pro 17)
“This string lacks the kind of “cupping” and power that would truly separate it form the pack.” 4.0 male all-court player using Head CrossBow 6 strung at 52 pounds CP (Gamma Revelation 17)
“Control is good, but touch and comfort are lacking.” 3.5 male baseliner with moderate spin using Prince O3 Blue strung at 64 pounds LO (Gamma TNT2 17)
“The crosses must be strung carefully, so as not accelerate the fraying that occurs during play. String movement is fairly high.” 3.5 male baseliner with moderate spin using Prince Thunder Rip OS strung at 64 pounds LO (Unique Big Hitter Blue 17)
“The mains have high coil memory and the crosses kink a lot. This hybrid has a great combination of control and power. String movement is fairly high.” 4.0 male baseliner with moderate spin using Volkl DNX 3 strung at 60 pounds CP (Babolat VS Touch 16)
“This is too stiff for my taste. For players who prefer non-poly multifilaments, lower tensions are advised.” 4.0 male all-court player using Wilson Triad 4.0 MP strung at 64 pounds CP (Gamma Live Wire 17)
“No feel or comfort. A little extra spin.” 5.0 male baseliner with heavy spin using Wilson K Six.One (68 Holes) strung at 64 pounds LO (Wilson NXT Tour 16)
“Handle the gut with extra care.” 5.0 male baseliner with heavy spin using Head MicroGEL Radical Team MP strung at 57 pounds CP (Gamma Professional 16)
(Strings normally used by testers are indicated in parentheses.)
| EASE OF STRINGING
(compared to other strings)
|Number of testers who said it was:|
|about as easy||25|
|not quite as easy||7|
|not nearly as easy||1|
| OVERALL PLAYABILITY
(compared to string played most often)
|Number of testers who said it was:|
|about as playable||11|
|not quite as playable||7|
|not nearly as playable||1|
| OVERALL DURABILITY
(compared to other strings of similar gauge)
|Number of testers who said it was:|
|about as durable||9|
|not quite as durable||5|
|not nearly as durable||0|
|From 1 to 5 (best)|
|Playability (8th overall)||3.9|
|Power (6th overall)||3.8|
|Control (6th overall)||3.9|
|Spin Potential (19th overall)||3.5|
|Resistance to Movement||3.7|
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.
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