MAC Powersphere Driver by Burrows Golf

MAC Powersphere driver and Burrows Golf explainer

The MAC Powersphere driver was introduced at the 2003 PGA Merchandise Show by a company called Burrows Golf and drew the endorsement (and investment) of 1981 British Open champion Bill Rogers.

The "MAC" in MAC Powersphere by Burrows Golf stands for "magnitude amplification cavity." Sounds fancy, and it was - an easier way of describing it might be to say that there was a hole in the sole.

Basically, the "Powersphere" design by Burrows was an early version of what was sometimes called "inverted cone technology," among other names: an internal cone - protruding up from sole into the interior of the clubhead - to direct energy back to the clubface.

The story behind the driver is this: Bruce Burrows was at a driving range on a cold day in 1995, hitting balls. And as players frequently experience hitting hard range balls on cold days, Burrows' hands were feeling the sting of the vibrations running up the shaft of his club. That's when it hit Burrows: Vibration is just wasted energy. What if there was a way to keep that energy from being wasted? To keep it in the clubhead, where it could be transferred into the clubface and ball, rather than traveling up the shaft?

The "inverted cone" - what Burrows called the MAC Powersphere - was his answer. And the MAC Powersphere driver drew good reviews from many quarters. Alas, it didn't draw enough business, and the technology was adapted and expanded on by other companies. Burrows Golf went out of business within a couple years. (We've seen drivers carrying the MAC name and using the Powersphere technology marketed under a Simon Golf brand, but know nothing about that company or brand. It likely picked up the patents and branding cheap and later reintroduced the driver as a discount offering.)

You still occasionally see a MAC Powersphere driver or fairway wood for sale used, and if you want to pick one up, you'll be getting a good club - but a good 2003 club.

Here is our original review of the Burrows Golf MAC Powersphere driver from back in 2003:

Review: MAC Powersphere Driver by Burrows Golf

Rating: 4.5 (out of 5) stars


  • Less distance loss on heel, toe hits.
  • Less vibration travels up shaft - easier on hands.
  • Quick-Fit system offers more than 500 specs.


  • Hit the ground, pay for it: cone catches turf.

Specs and Keypoints

  • An inverted cone in the sole makes it appear as though there's a hole in the sole.
  • The inverted cone is made of paper-thin titanium, and the clubhead is a titanium clubhead.
  • Clubheads come in 421cc and 350cc sizes.
  • The 350cc size offers your choice of a square face or draw face (2 degrees closed).
  • Various loft options are available, depending on clubhead size, ranging from 6.5 to 10.5 degrees.
  • Stock shafts are Grafalloy HotFlex or Graphite Design HotFlex, but special orders are possible.
  • Standard lengths are 45.75 for the 421cc and 45.5 for the 350cc.
  • Standard lie is 58 degrees.
  • Stock grips are Tour Velvet; custom order grips are also available.
  • Quick-Fit and Quick-Grip fitting system allows more than 500 variations.

MAC Powersphere:  The 'Conehead' Driver

What jumps out about the MAC Powersphere is the "powersphere" itself - an inverted cone (meaning it goes up into the clubhead) on the sole of the club. "MAC" stands for "magnitude amplification cavity." When the clubface strikes the ball, creating vibrations, the cone reflects vibrations back into the clubface and ball. Which means far less wasted energy and a clubface that is hot along its entire face.

Bill Rogers, 1981 British Open champion, told me no driver he's used has been more forgiving on heel and toe hits. Another advantage of the cone: Reflecting vibrations back into the clubface means far less vibration travels up the shaft - a great feature for golfers with hand, wrist or arm problems.

The Bottom Line: The MAC Powersphere driver by Burrows Golf is an innovative club that puts vibrations to work for the golfer.

Burrows' Other Innovation

The MAC Powersphere driver was accompanied by a portable fitting cart that allowed green-grass pro shops to quickly get customers into the right specs. It was one of the first such systems that allowed for quickly swapping out shafts.

Burrows called it the Quick-Fit and Quick-Grip system. A MAC Powersphere Fitting Bag on display in a pro shop included various shafts, heads, and grips - enough to create 510 different variations of the club. Using the "Six-Point Driver Fitting System," parts were swapped out to accommodate golfers in loft, face angle, shaft type, shaft length, grip style, and diameter.