
Until recently I had never heard of the tennis string Diadem Solstice Power or the Diadem brand. I had orginailly found them by following their Instagram feed (you can follow TennisThis on Instagram HERE). I was intrigued by the “Star Core Technology” that Diadem claims to reduce tension loss and produce incredible spin; so obviously TennisThis.com had to try some to do a string review! I reached out to them with genuine interest in their co-poly tennis strings. They were incredibly generous to send me a few sets of their Diadem Solstice Power tennis string for review.
What is Diadem Star Core Technology?
Star Core Technology is constructed with a patent pending hexagram cross section. This technology uses a six-pointed geometric cross section that equally distributes contact between strings, thereby minimizing friction significantly to allow for explosive snap back. At the same time the star shape provides a larger surface area creating more bite on the ball at impact to achieve maximum spin potential.
Diadem Solstice Power tennis string installation
Diadem recommended I drop my starting tension 4 pounds on my first go with the string. I decided to lace up my Yonex EZONE Ai 98 at a starting tension of 40# on both mains and crosses in a two piece string-job. I have gone as low as 39# on some strings, basically just to see how the string would feel, though I was a little reluctant to go all the way down to 40# on a string that I had never tried before in my life. A little skeptical at this point of my Diadem Solstice Power review.
Initially, I pulled the Diadem Solstice Power strings through the frame very carefully; afraid to damage the sharp edge string shape in the weaving process. I also took great care in avoiding as much string twist as possible while weaving. I wanted the Diadem Solstice Power to be as straight and aligned as possible to get the maximum benefit of the Starcore Technology and the spin potential. Although the strings felt firm to the touch, I must admit that I was surprised at how incredibly smooth and easy it was to install the Diadem Solstice Power. Very impressive.
Diadem Solstice Power on-court playtest
My first go with the Diadem Solstice Power tennis string I wasn’t too pleased with the lower tension; it was powerful but I had zero feel and little control. I was a little bit everywhere with this string installed. Even though I couldn’t really get my game on par with this string, I did appreciate the potential because of the amount of free spin I was getting off my forehand and backhands.
I decided to cut out the current string job and put in another set at a higher tension, 44#, and get back on court to try again.
After a not very impressive first playtest, I was ready to go with a freshly strung Yonex and a clear mind to give Diadem Solstice Power another shot. No regrets.
At the higher tension, I had my control, I had my feel, I had my spin, and I had my power. I absolutely fell in love with this tennis string!
Diadem got it right in designing this tennis string, the all-around goodness of the Solstice Power is on point. It’s a plush blend of power, control, and spin. All of these ideal attributes are what the modern tennis player needs in their equipment.
The amount of spin I was able to produce, with directional power, was simply incredible. Granted, I had flatten my forehand out a little because the strings were producing so much topspin that many of my more-than-semi-western forehands were landing too short across the net and allowed my opponent to sit back on the baseline and really rip into his forehand or backhand. After flattening out to a more regular western grip on the forehand, I was really hitting deep penetrating shots that gave my hitting partner the fits to get good timing on the ball – especially since the tennis ball easily jumped up and in to them. I was having a blast on the topspin!
As you can already imagine, Diadem Solstice Power was a gem on serve; not only was placement all too easy, power came naturally. According to my hitting partners, my serves were “Not fast like quick, but hard and heavy!”
While I love to hit big, flat, first serves, I also like to put a little action on my serves. Diadem Solstice Power really blew me away just how much kick I was able to get; best of all it came fairly easily – good tempo and a sold grip produced crazy kick! My absolute favorite serve to hit with this string was a wide topspin serve to my, right-handed, opponents’ backhand. The height I was able to get was incredible, often at or above his head (he’s roughly 5’10”) with enough spin to send it away from his strike-zone.
Diadem Solstice Power comfort
In the past, I have suffered tenderness in my arm because of string firmness; though I have used flexible tennis

racquets, sometimes it’s inevitable to come across some tennis strings that just cause arm pain. It’s just the nature of our sport.
However, with Diadem Solstice Power, I didn’t find that I had a hint of arm tenderness. In fact, I found that after I played for a few hours with this string, at the right tension, my arm felt energetic! I had no arm fatigue, no pain, no soreness, just more desire to hit another bucket of balls. I was amazed.
Diadem Solstice Power durability
Like most shaped tennis strings, after a little bit of play, the sharp edges of the string would wear down and you’d end up with another round tennis string. The difference in Diadem with their Star Core technology was pretty much the opposite of what the others do. I literally played the Solstice Power for about 8 or 9 hours before the edges started to wear down. Not only that, but the notching was close to nill in the first several hours of play; this was key for the crazy spin, the snapback lasted significantly longer than many other strings.
Diadem told me that all of their tennis strings are designed to hold tension longer than most tennis strings on the market. I do believe this to be true, Diadem Solstice Power held its tension far longer than many other tennis strings that I’ve reviewed. However, as the tension “loosened” up a little bit as I played on, I liked it more and more – just not that low right off the machine.
Similar to most polyester and co-polyester tennis strings on the market, they break. I played Diadem Solstice Power until I popped a main; it wasn’t a bad thing, in fact I should have cut them out before it got to that point, I was just enjoying the tennis string so much that I just wanted to see how much life I could get out of them. Total string life from first ball to last: about 11 hours. Honestly though, the last couple of hours were a little comical as I could hardly keep the ball inside the court and was basically goofing around until they broke.
Diadem Solstice Power final thoughts
This is an absolute must try tennis string for 2015! You should buy a couple of sets, just in case you don’t get the tension just right the first time. I do recommend starting at your normal tension first and potentially dropping 2 pounds if you are determined to try a lower tension. You’ll get a great all around experience with Diadem Solstice Power tennis string. Just try it!
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