This article serve to summarize what is frequency matching and frequency matching in a set. It is not intended to be a detailed discussion on the subject matter. Many technical discussions are already available on the net.
Webster’s dictionary defines Frequency as; “the number of times any action or occurrence is repeated in a given period”. and “in physics,..the number of vibrations or cycles per unit of time”. From the second definition we can show that, simply stated, “Frequency is a dynamic (in motion) measurement of shaft flex or stiffness stated in terms of cycles per minute (cpm) of vibration, when the shaft is held firmly in a clamp and the shaft is plucked”. The HIGHER the FREQUENCY the STIFFER the SHAFT.
The concept of frequency matching is not new but until the introduction of the parallel tip or unitized golf shaft, frequency matching was not a practicable consideration since tapered tip shafts could not be tip trimmed and easily installed in the hosel of the club head. And due to this is never practically possible to frequency match a set of OEM heads as they are almost always come in taper hosel.
The objective in recommending a particular type of club to a golfer should be to match the golf club by Total Weight, Head Weight, Length, Grip Size, Lie and Shaft Flex to both the golfer’s strength and swing tempo, while maintaining the same feel throughout the set of clubs.
With current video technology, we can easily see that the weight and motion of the clubhead causes the shaft to bend, thus storing energy in the shaft. If the golfer is to hit a good shot, basically two things must happen during the downswing. The clubhead must return square to the intended line of flight, at separation (Not impact, yes, there is a difference if you look at the number at impact and at separation), if the ball is to be hit at the target, and the stored energy must be transferred to the ball if the golfer is to attain maximum distance from the club being used.
There are many theories, systems and methods for frequency matching. The most common will be matching your swing speed to the butt frequency. But yet, we think there are many more parameters that need to be considered. E.g. I can have two shafts measured to the same frequency, but have very different wall thickness, different material, different taper rate and construction and gives very different result.
Frequency matching in a set
In a frequency matched set of clubs, the frequency or stiffness difference between successive clubs is equal. It does not mean that each club in the set is the same stiffness or frequency. Golf clubs traditionally get stiffer (have a higher frequency) as they become shorter.
So what should the cpm difference between clubs? Some say 4 cpm, some other will like 2cpm. There was never a real standard although most will say 4 cpm for a 0.5″ difference.
Building a frequency matched set is always a challenge and only the finest components (both heads and shafts) can and should be used. No taper shaft or taper hosel head. One of the best shaft for this purpose is the True Temper Black Gold. Head wise, they need to be manufactured to a very tight tolerance of weight. Any fluctuation is weight between heads will have major impact on the matching process.