Category Archives: Power
Right here…Right now! Squared
More Linearity
Every string we use and even string we do not use goes through our Questron testing cycle. We have discussed this before, and a video on this site shows the Questron in action. We have updated the Questron significantly since the video was made…and it isn’t quiet.
We want to discuss “linearity” and how it can help when choosing a string setup.
We used these strings recently, and they were not chosen for any reason other than availability.
The first graph shows highly linear strings. The straighter the line from “0” to “fail,” the more linear and consistent the string is throughout its life.
So, what does linearity do for me?
- Maintains tension
- Minimizes energy loss
- Maintains playability
- Maintains consistency
- Maximizes control
- Maintains predictability
- Provides confidence throughout your match
This property is essential to us. That is why we offer an alternative to non-linear strings.
If you would like this information for your favorite string, please let us know, and we will try to provide it for you nd all other readers!
Head Auxetic 2 Radical Pro 2025
The Radical Pro represents the pinnacle of a player’s racquet. So, this review is based on our desire to see how much power we can squeeze out of it through string bed stiffness.
The following specifications explain why this racquet’s natural properties make it a powerhouse.
This 98-square-inch racquet packs a powerful 339-gram weight with a very easy-to-handle 331 swing weight!
With this racquet, you will not be pushed around by big hitters.
As tested, this racquet has a stiffness rating of 66, which is moderately high. However, with an effective stiffness of 27.1, it is well within the range of any player who can benefit from the other performance factors.
As you can tell from the picture, the racquet is ORANGE. These pictures are the skills of Bobby Diviliansky, a high school student who just happened to stop at the World Headquarters! His brother Ryan is a client, so he had a reason to be here.
| Manufacturer | Head |
|---|---|
| Racquet Model | Head PT57A2 Auxetic Coat - No Grip Pallet |
| Reference Tension | |
| String | |
| Machine Used | |
| String Bed Stiffness - RDC | |
| String Bed Stiffness -FlexFour | |
| Strig Bed Stiffness - SBS | |
| String Bed Stiffness - ERT | |
| Racquet Flex, RDC,No Pallet | 62 |
| Racquet Flex, FlexFour, No Pallet | 57 |
| Racquet - In Plane Stiffness | 462.2 |
| Weight, Grams | 255.6 |
| Weight, Ounces | 9.016 |
| Balance, mm | 354 |
| Balance, Inch | 13.94 |
| Length, Cm | 68.2 |
| Length, Inch | 26.850 |
| Head Width | 9.437 |
| Head Length | 12.748 |
| Head Area, cm^2 | 611.3 |
| Head Area, Sq. Inch | 94.75 |
| Beam Height @ Grip, mm | 21.1 |
| Beam Height @ Mid, mm | 20.3 |
| Beam Height @ Tip | 20.3 |
| Beam Width @ Grip, mm | 11.0 |
| Beam Width @ Throat, mm | 11.0 |
| Beam Width @ Mid, mm | 11.7 |
| Beam Width @ Tip, mm | 11.5 |
| Number of Main Strings | 18 |
| Number of Cross Strings | 20 |
| Ratio | .634 |
| Main String Grid Inch/mm | 7.18/182.3 |
| Cross String Grid Inch/mm | 9.51/241.5 |
| Density (% of head filled with string) | |
| Average Cross String Space | |
| Average Main String Space | |
| Dynamic Tension, Kp, ERT | |
| Dynamic Tension, Lbs/in | |
| First Moment, Nm | |
| Polar Moment | |
| Torsional Stability | |
| Swing Weight, Kg/cm^2 | 285 |
| Swing Weight, Ounces | |
| Swing Weight Calculated | 318.5 |
| Power, RDC | |
| Control, RDC | |
| Manueverability, RDC | |
| Power, Calculated | |
| Head Points | |
| Head Weight, % | |
| Center of Percussion | |
| Dwell Time, ms | |
| Efective Stiffness - lbs | |
| K, Lb/In | |
| Recoil Weight | |
| Twist Weight | |
| End Weight | 81.2 |
| Tip Weight | 177.6 |
| 9 O'Clock | 87.2 |
| 3 O'Clock | 87.9 |
| Butt End | 88.1 |
| COF, Main | |
| COF, Cross | |
Power from Head Radical Pro
As with many of the Head “Pro” series racquets, they have been considered control racquets, not necessarily powerful.
We set out to see what kind of “power” number we could get using string bed stiffness only. Obviously, more swing weight and maybe more overall weight would do it, but the Head Radical Pro is already at the top of these specifications.
The following video is a look at our software data.





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