Equipment

How the idea of shaft frequency began

Published

9 years ago

Jun 4, 2017

Forty years ago, Kim Braly and his father Dr. Braly went down to West Palm Beach to visit Wilson Golf, and that trip forever changed the way the golf industry thinks about the shafts in golf clubs.

“My father and I invented frequency matching,” Kim told me.

“And what’s that?” I asked.

“It’s the process of matching the stiffness of the shafts in your clubs to the heads so you can hit a golf ball rather than snap the shaft or hit the ball all over the place,” Kim said.

OK, that got my attention. So I ask how he stumbled upon the idea.

“My dad was an engineer and got into golf,” Kim said. “Eventually, I got interested in golf as well. In the early 1980s, we went to see the original ‘Iron Byron.’”

A modern-day golf robot at Titleist’s Manchester Lane Test Facility.

Iron Byron was the first club-testing machine, and it was modeled after smooth-swinging legend Byron Nelson. It’s basically an early robot — a motor in a box with an arm — built to use a regular golf club to hit a golf ball.

Kim and Dr. Braly watched the engineer operating Iron Byron put a club into the mechanical arm, place a ball in front of the club face and then press a button to swing the club. The result: perfection. It produced a high, piercing ball flight that was hit on a rope, not far removed from the storied ball flight of Nelson himself. This was followed by another and another. Kim and his father were ecstatic.

With great anticipation, they watched the engineer load the next club. The results were much different. Balls flew all over the place. The dispersion was awful. The Wilson engineer operating Iron Byron slowed down the machine. Balls flew shorter distances, but they landed closer together. The dispersion had been reduced. This was the inception of their game-changing idea; dispersion was a result of certain shaft characteristics matched with a club head and swing speeds. This “AH HA” moment changed how we fit and purchase golf clubs today.

Based on this observation, Kim and Dr. Braly designed a method to measure the performance of a golf shaft. Later, this led to the concept of frequency: very simply, stiffness is not the letter on the shaft, but a measurement based on characteristics like weight of shaft, weight of the head, length of the shaft and several other characteristics. The year was 1977 and they submitted a patent on this idea called “Frequency Matching.”

Armed with the power of measurement, Kim was ready to change golf shafts forever. He and his father started traveling the PGA Tour, and in doing so became the first “PGA Tour Van.” Over the last 40 years, Kim has worked as a researcher and designer, mastering the golf shaft. He’s worked at True Temper, Royal Precision and is currently as the head designer of research and development at KBS Golf Shafts.

Kim working with a player on his golf equipment.

In 2008, Kim launched a shaft company called KBS, which became the fastest growing shaft company in golf. Since that time, the company has gotten some of the best golfers in the world to use its shafts products, including Rickie Fowler, Justin Rose and Phil Mickelson.

The next time you’re struggling with shots that fly sideways, think about Kim and Dr. Braly. You might want to try try being fit for shafts if you haven’t already, because they may just be the most important part of your golf club.

Related Topics:shafts

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B.M. Ryan

B.M. Ryan, an entrepreneur and scientist, is a passionate golfer who loves his local muni. Armed with a keen interest in the game, a large network of friends in the industry, Brendan works to find and produce unique content for GolfWRX.

13 Comments

TeeBone

Jun 7, 2017 at 5:34 pm

Further, frequency matching a set doesn’t mean that the clubs all have the SAME shaft flexibility, only that the DIFFERENCE in flexibility is uniform from club to club. As the clubs get shorter, frequency and stiffness increase. Add to this the fact that as the clubs get shorter and heavier, they are swung at a slower speed. In the end, each shaft in a set flexes more and more overall as the clubs get longer. This silly “dispersion” theory suggests that a shaft must flex a specific amount to behave consistently.

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TeeBone

Jun 7, 2017 at 2:39 pm

Tour players, unless they have a specific shaft manufacturer deal, are free to play whatever shaft they want. Their decision to play graphite over steel has to do with performance, not money.

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TeeBone

Jun 7, 2017 at 2:27 pm

So Iron Byron, set at any particular swing speed, only reproduces the same ball flight with one specific shaft flex? This “dispersion” theory would mean that the same shaft can behave quite differently, from swing to swing, for an otherwise same swing input. Nonsense. There is no mention of this in any of the best-regarded scientific studies of shaft flexibility. This is a made-up marketing story designed to sell equipment.

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Ned

Jun 6, 2017 at 8:06 am

Brunswick Golf developed the Frequency Matching System in 1981!

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- Rico
  
  Jun 6, 2017 at 4:04 pm
  
  The article states that the Braly’s submitted a patent for “Frequency Matching” in 1977.
  
  Reply Report comment
J.

Jun 5, 2017 at 7:15 pm

And stiffness of an EI profile may be invisible to CPM matching? Does SST PURE shaft alignment work better?

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- Skip
  
  Jun 7, 2017 at 1:18 pm
  
  SST pure is pure Kool-Aid. Drink it if you so choose.
  
  Reply Report comment
tim crider

Jun 5, 2017 at 4:05 pm

There is no doubt that shots can be saved every round by every player with changes from the shaft to the swing weight to the compression of your golf ball,,, hell practicing on the driving range could improve your game. There is a lot to know about this game and if you have the money and the time you may be able to cash in on these findings. Think how much better play got when shafts changed to steel from hickory. A lot to know and even more to learn. How much more can be found and improved, it was a very good article.

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Charles Bartholomew

Jun 5, 2017 at 3:38 pm

Interesting article. A little history lesson now and then is a good thing.

Reply Report comment
cgasucks

Jun 5, 2017 at 8:20 am

If the Iron Byron can make crappy shots with a shaft that isn’t compatible with its swing speed, imagine it with a human being.

Reply Report comment
- talljohn777
  
  Jun 5, 2017 at 12:14 pm
  
  Yes, if you have a club shaft that is too soft you can slow your swing down to allow the clubhead time to catch up and square, but why would you want to do that? The preference would be to hit a club that matches your top swing speed allowing you to get the most out of your swing.
  
  Reply Report comment
artie j

Jun 5, 2017 at 6:59 am

I didn’t know the backstory. Very cool article Ryan

Reply Report comment
SH

Jun 4, 2017 at 10:25 am

Yup, awesome

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Equipment

Interesting clubs at top of bag – GolfWRXers discuss

Published

13 hours ago

Jun 3, 2026

Will Schube

In our forums, users are talking about top of bag setups that are non-traditional or thought-provoking in some way. Original poster @SuperSpurs106 inquired about other members who might use unorthodox set-ups to help with gapping issues or weak spots.

They wrote:

“I currently have a PING G430 driver, TM Qi35 3W and a TM Qi4D 7W. Driver and 7W are fine but can’t get on with my 3W and have always struggling with this club over the years. Thinking of adding a 2H which I know would look odd. Just wondering if anyone else had a weird set up at the top of their bag?”

Our members in the forum have offered up their thoughts and personal experiences with non-traditional top of bag set-ups, and their reasoning for thinking outside of the box to begin with. Here are a few posts from the thread, but make sure to check out the entire discussion and have your say at the link below.

BowMain42: “Don’t worry about what “looks” odd. If the club does what you need it to do, it’s the right club.”
scooterhd2: “I cant hit 3 woods either. Thats why I roll with a unicorn XL Hibore 2 wood. 400 cc head at 16 degrees of loft and its just a monster 3 wood off the tee. Off the deck, we are playing the f6 baffler. 5 wood at 41.75 inches and its easy to control.”
phizzy30: “I had driver, 3 metal, 2/4 hybrid once upon a time as a higher ss player. 4 hybrid is gone and in place is a driving iron nowadays. I don’t think what you’re proposing is weird in anyway, however the yardage gap might be glaringly huge between driver and 2 hybrid. What is it about your 3 metal that has got you all messed up? You could always go 4 metal with shorter shaft and see if that works.”

Entire Thread: “Interesting clubs at top of bag”

If you aren’t a member, join us in the GolfWRX forums today!

Equipment

Members of the Mini Driver Club – GolfWRXers discuss

Published

13 hours ago

Jun 3, 2026

Will Schube

In our forums, one user has gone searching for fellow users of a mini driver. In a post, @TightFade asked for other mini driver users to chime in with their weapon of choice, the reason for employing a mini, and what club follows it in the bag.

@TightFade asked:

“What mini are you playing? What spot in the bag did it take over? What’s the next club after it? For me: Elyte mini 13.5. Replacing 3w. Next up club looks like it’ll be 5w.”

Our members in the forum have been sharing their own bag setups featuring the mini driver, and the various reasons they purchased one in the first place. Here are a few posts from the thread, but make sure to check out the entire discussion and have your say at the link below.

RCGA: “Ping G430 Max 12* ‘Thriver.’ Next club is a 4w and 2i (I play a weird course).”
JMB3: “R7 at 12.75 with Diamana BB 63s. 3w replacement. Next Club: Elyte Ti 5w at 17*.”
ColdOkieGolf: “R7 15.5 turned down to 13.5 It replaces the 3w. I found it surprisingly easy to hit off the deck, and it’s very rare that I need or want to hit something beyond 250 from the fairway, so next club is my 7w.”
ChaosTheory: “I’m sub-90 MPH with driver. But I’m able to hit DOD. I have been wanting something like the R7 15.5, so I just ordered one. I have a spot in the bag so nothing has to go. But I could see it replacing my trusty 4 wood, which I never use for approach shots. Just tee shots and lay ups. If I drop the 4 wood, I will turn my 7 wood down to ~20 degrees and will have good gaps. I recently tried a thriver build: 12 degree driver turned to 14, with a heavier 44 inch shaft and added head weight. I hit it great. Very accurate and not overly high, but the problem was that it sometimes went as far as a typical drive. And that’s not what I needed. So I will probably turn the 15.5 up to 16.5 or even 17.5. It’s all theoretical at this point. ?”

Entire Thread: “Members of the Mini Driver Club…Check In.”

If you aren’t a member, join us in the GolfWRX forums today!

Whats in the Bag

Chris Gotterup WITB 2026 (June)

Published

13 hours ago

Jun 3, 2026

GolfWRX Staff

Chris Gotterup had >14 clubs in his bag when photographed prior to the Memorial Tournament.

Drivers: TaylorMade Qi4D (8 degrees), Ping G440 LST (9 degrees @8), Ping G440 LST (7.5 degrees)
Shafts: Project X HZRDUS Smoke Grey 6.5 TX 70 g, Project X HZRDUS T1100 Handcrafted 6.5 TX 70 g, Project X HZRDUS Smoke Grey 6.5 TX 70 g