Category Archives: Technology

Head Extreme Tour

Head is, I believe, going to expose and promote the Extreme Series to a greater extent than before.

Why do I think that?  Because I am holding in my very own hands a Head Extreme Tour!  This 98 square inch racquet continues the Graphene 360+ technology which has become popular in the last several releases of Head Racquets!

The new Extreme series will be shipping in July so we can’t show many pictures except the all-black version I am holding.

Head Extreme Tour

The other Extreme models will be:

Extreme MP – 100 square inch head size, 300 gram

Extreme S – 105 square inch head size, 275 gram

Extreme Lite – 105 square inch head, 265 gram

Extreme PWR – 115 square inch head, 230 gram

Extreme Jr – 100 square inch head, 240 gram

All of this series continues the “extreme” optic yellow colorway but it is now complemented by a really nice grey upper shaft and hoop!  The optic yellow grip may be over the top but that is easily changed.

The Extreme Tour is fitted with a TK82S grip pallet for a comfortable rounder feeling.

Take a look at the specs here:

ManufacturerHead
Racquet ModelHead Extreme Tour
Reference Tension55 lbs - 24.9 kg
String
Victrex PEEK fiber Experimental 7718
Machine UsedTrue Tension Professional
Static
ASPS, RDC52
ASPS, FlexFour63.5
Racquet Flex, RDC62 - After stringing
Racquet Flex, FlexFour40
Weight, Grams320
Weight, Ounces11.29
Balance, mm323
Balance, Inch12.72
Length, Cm68.6
Length, Inch27.008
Head Width9.59
Head Length12.87
Head Area, cm2625.1
Head Area, Sq. Inch96.9
Beam Width, mm, Shaft, Center, Tip22, 23, 21
In Plane Stiffness, Pounds/In359.5 Lbs/In.
In Plane Stiffness, Kg/cm 163.0 Kg/cm
Number of Main Strings16
Number of Cross Strings19
Ratio Cross/Mains.627
Main String Grid7.12
Cross String Grid9.63
Density (% of head filled with string).708
Average Cross String Space.507
Average Main String Space.445
Dynamic
Dynamic Tension, Kp, ERT35
Dynamic Tension, Lbs/in195.76
First Moment, Nm.794
Polar Moment322
Torsional Stability16
Swing Weight, Kg/cm2306
Swing Weight, Ounces10.79
Swing Weight Calculated333.9
Power, RDC47
Control, RDC55
Manueverability, RDC83
Power, Calculated 1856.5
Head Points6.30 (negative = head heavy)
Head Weight, %47.1%
Center of Percussion20.8
Dwell Time, ms, No Swing8.62
Effective Stiffness - lbs28.3
K, Lb/In (SBS) RDC166.67
Recoil Weight149.14
Twist Weight220.52
End Weight 132.8
Tip Weight 190.4
9 O'Clock Position96.6
3 O'Clock Position98.3
Butt Cap Position126.3

 

String Tension Testers…Friend or Foe?

The StringMeter is a device used to check the tension of an individual string. There are other versions of similar functionality, but this is what we use, and I will start with that.

Interestingly, this device traces its design to a tool that is used to check mainstay tension on a sailing vessel.

It is clear that our devices are well used, so they must be a “friend,” not a “foe”! And to that, I would say yes! The two (2) units shown here are “calibrated” units. One device is “free string,” and the other is “strung string.” These are different scales and very important for accurate information.

String Tension Tester

When we evaluate string or stringing machines, one of the most important values is the string tension with only the main strings installed. Using the “free string” scale, we check every main string and record the number.

Once the racquet is fully strung, we can check some center main strings and center cross strings with the “strung string” scale and see the variation. The difference between the two is the “natural ratio” of the racquet.

In addition to the stringing machine review use of the StringMeter, we also use it to calculate our “accuracy index.”

For this, we use the “strung string” scale and check each main string tension from left to right and every cross string tension from top to bottom and compare the actual numbers to the calculated numbers based on a non-distorted racquet. This spreadsheet shows how accurately the ball will come off of the racquet face.

The “efficiency index” tells us how much the racquet needs to change shape to reach that “index.”  

These are all essential functions of the StringMeter and String Tension Tester from Gamma Sports.

But, what if the StringMeter or other device is used without knowing what it is telling the user?

This is the “foe” part!

This would be the case if a customer with such a device has a racquet strung at say a reference tension of 55 pounds. The customer then uses the method to check the tension and finds that it is not 55 pounds or even close! The customer is not going to be happy!

If the customer knows what to do, they can check the main string tension as soon as they can after stringing, then, later on, to see how much the string has stretched without regard to the reference tension.

It is what it is!

When the racquet is no longer performing it would tell the customer how much the tension can deteriorate before stringing is required.

So, these devices are very useful for individual string tension but no so much for “string bed stiffness,” which is the total string bed as a ball impacts it.

We will look at some of the “string bed stiffness” devices in a future post.

 

 

I Get It! Maybe… or Maybe Not!

When we do a racquet review we try to deal with numbers!  Static and dynamic numbers to be precise.  We do this so each racquet can be referred to by properties and not just by subjective comments.  Make no mistake, subjective comments are good and can be used in fact to generate numbers!

Here is an explanation of the numbers and what they can mean to you.

It is well known that 5 players will have 5, or more, different “comments”, so having numbers provide a database, or history, of what works for what player style.  With that information, a new client can be playing with their “perfect” racquet is a very short time instead of trying a zillion different models.

This is important because players may not be using the best racquet for them because they rely on assumptions instead of numbers!  The very worst assumption is “I need a light racquet because I am just getting back in the game”.  The second worst assumption is “I need a big head with a big sweet spot because I am not very good”.  The third worst assumption is “I don’t need very good string because I am not very good”.

Bogus assumptions, every one of them!

As we look over our client data some things are clear and should become performance metrics;

  1. Total weight should be not less than 10.5 ounces (300 grams).
  2. Swing weight should not be less than 10.5 ounces (300 grams).
  3. Torsional stability should not be less than 15 units (typically grams).

With these metrics, you are off to a great start with a new racquet, or if you are beginning a new racquet search these numbers will be helpful.

 

 

 

 

 

Head Graphene 360+ Speed MP Lite

The Head Graphene 360+ Speed MP Lite may be the perfect racquet for a player looking for a thin(er) beam, 100 square inch head size, slightly lighter than most MP racquets!

As you will see in the specifications this racquet is about 28 grams (1 ounce) lighter than the MP model, and, just a little more flexible, or better said, less stiff!

Forty-nine point nine percent (49.9%) of the total weight resides toward the head of this racquet, so if you think in terms of “points” it is 0.16 points head light.

Some customization will make this a racquet that you can stay with for a long time. As your skills advance, so can the racquet!

Head Graphene 360+ Speed MP Lite

As I am working on this post I realize how much trouble it is to switch between racquet reviews for comparison so I am including a link to the Head Graphene 360+ Speed Series Comparison.

 

 

ManufacturerHead
Racquet ModelHead Graphene 360+ Speed MP Lite
Reference Tension56 lbs - 25.4 kg
String
Victrex PEEK fiber Experimental 7718
Machine UsedTrue Tension Professional
Static
ASPS, RDC51
ASPS, FlexFour62
Racquet Flex, RDC60 - After stringing
Racquet Flex, FlexFour49
Weight, Grams293
Weight, Ounces10.34
Balance, mm342
Balance, Inch13.46
Length, Cm68.5
Length, Inch26.97
Head Width9.68
Head Length13.06
Head Area, cm2640.8
Head Area, Sq. Inch99.3
Beam Width, mm, Shaft, Center, Tip23, 23, 23
In Plane Stiffness, Pounds/In307.3 Lbs/In.
In Plane Stiffness, Kg/cm 139.4 Kg/cm
Number of Main Strings16
Number of Cross Strings19
Ratio Cross/Mains.624
Main String Grid7.30
Cross String Grid10.62
Density (% of head filled with string).780
Average Cross String Space.559
Average Main String Space.456
Dynamic
Dynamic Tension, Kp, ERT35
Dynamic Tension, Lbs/in195.76
First Moment, Nm.782
Polar Moment323
Torsional Stability15
Swing Weight, Kg/cm2308
Swing Weight, Ounces10.86
Swing Weight Calculated342.7
Power, RDC46
Control, RDC57
Manueverability, RDC81
Power, Calculated 1835.6
Head Points0.16 (negative = head heavy)
Head Weight, %49.9%
Center of Percussion21.0
Dwell Time, ms, No Swing8.91
Efective Stiffness - lbs27.6
K, Lb/In (SBS) RDC163.46
Recoil Weight138.67
Twist Weight205.8
End Weight 105.8
Tip Weight 186.5
9 O'Clock95.1
3 O'Clock94.5
Butt Cap103.0

Head Graphene 360+ Speed Pro

This is the “PRO est” of the new Speed series because it says so right on the tip of the racquet and it carries an 18×20 string pattern, so there!

However, do not be intimidated by the “Pro” label!  You will see by the specifications that this is a racquet that can be used by any player wanting to maximize their current skillset.

A couple of good reasons for this assessment is the wonderful flex of RDC 60!  The overall weight and swing weight are there as a good beginning but can be adjusted to suit any player.

Typically 18×20 string patterns are not considered spin-friendly but the dense pattern can be used to your advantage by reducing string bed stiffness, thus dwell time and therefore spin potential.  In other words, this pattern is highly customizable!

Head Graphene 360+ Speed Pro

If you value string life the 18×20 pattern can reward you with some increased durability.

As we mentioned in the Graphene 360+ Speed MP review there didn’t need to be many changes from the previous version and probably the most noticeable change is going to be the color “flipping” and a little increase in swing weight.

The numbers will tell the story.  Click here to see the Graphene 360 Speed Pro data from last year.

 

ManufacturerHead
Racquet ModelHead Graphene 360+ Speed Pro
Reference Tension56 lbs - 25.4 kg
String
Victrex PEEK fiber Experimental 7718
Machine UsedTrue Tension Professional
Static
ASPS, RDC55
ASPS, FlexFour66.5
Racquet Flex, RDC60 - After stringing
Racquet Flex, FlexFour43
Weight, Grams327
Weight, Ounces11.53
Balance, mm323
Balance, Inch12.72
Length, Cm68.5
Length, Inch26.97
Head Width9.69
Head Length13.06
Head Area, cm2641.2
Head Area, Sq. Inch99.4
Beam Width, mm, Shaft, Center, Tip23, 23, 23
In Plane Stiffness, Pounds/In335.2 Lbs/In.
In Plane Stiffness, Kg/cm 152.0 Kg/cm
Number of Main Strings18
Number of Cross Strings20
Ratio Cross/Mains.668
Main String Grid7.62
Cross String Grid10.37
Density (% of head filled with string).768
Average Cross String Space.513
Average Main String Space.414
Dynamic
Dynamic Tension, Kp, ERT37
Dynamic Tension, Lbs/in206.94
First Moment, Nm.812
Polar Moment336
Torsional Stability16
Swing Weight, Kg/cm2320
Swing Weight, Ounces11.29
Swing Weight Calculated341.2
Power, RDC45
Control, RDC57
Manueverability, RDC73
Power, Calculated 1908.2
Head Points6.14 (negative = head heavy
Head Weight, %47.2%
Center of Percussion21.2
Dwell Time, ms, No Swing8.58
Efective Stiffness - lbs28.7
K, Lb/In (SBS) RDC176.28
Recoil Weight159.71
Twist Weight229.85
End Weight 133.4
Tip Weight 192.8
9 O'Clock97.1
3 O'Clock97.5
Butt Cap131.0