Signum Pro Poly Plasma (SPPP)

Someone whom I string for became curious about this string. He gave me a few sets and asked for my opinion in return.

It was strange that he asked me, a known non-lover of poly (link), to help him assess the strings.

Online reviews have been mixed. Some claim SPPP plays soft and comfortable, while others felt it played stiff and dead. Many suggested tensioning it really low, like low-mid 40s lbs since the tension holding was very good.

After examining the string and taking some measurements, I decided to do up a full bed using proportional stringing (link) averaging about 48 lbs. I need all the power and comfort I can get...

Initial Impressions
- This is a stiff poly with very good tension holding indeed.
- The texture was not as slick as newer polys but neither is it rough nor textured. Just round.
- Most other polys would "slip" through my fingers as I weaved, but this string did not. So I figured the "ball bite" friction should be good for this string.
- Overnight, tension by frequency dropped only about 15 hz, which was impressive since most polys I tried loses about 40+ hz overnight unplayed.

Warm Up Rallies
- Only a very slight softening was felt after half an hour.
- Power was low and pocketing was minimal.
- An abnormally large number of shots hit the tape on the net. To me, this was another indication of its low power and correspondingly, a very low angle of rebound. Most of my shots normally clear the net two to three feet above.
- Control was decent but I struggled with spin. As a result, when I tried to step up the pace, the ball flew long.

Game Play
- Serves were very easy to place due to the tight stringbed. While I could hit down the "T" or out wide quite often, the pace was significantly slower than with other poly strings I used. 
- From my side, the serve did not feel offensive enough. I preferred a little more power, so I reduced the spin and hit flatter serves. Then it looked better.
- Return of serves revealed something very interesting to me. When contacted right at the sweetspot, ball impacts felt exceptionally nice, soft, comfy and powerful. But the ball flew long. Not up, but low and long. Even with follow-throughs above my shoulder.
- I noticed the same problem when returning very hard flat shots from my partner. "Trampoline" came to my mind. But only dead centre on the sweetspot. Other areas felt flat and stiff.
- This "trampoline" effect could be due to string loading, string timing and racket timing. Hard incoming shots, like serves, added a lot of "punch" to the stringbed, even with my compact swings. 
- This loaded both the strings and the very flexy racket. However, there was a huge rebound timing difference between the strings and the racket, resulting in this "loss of control" feeling. Since I cannot adjust the racket flex, I need to fine tune the tension to minimize this timing gap (link).
- With almost any poly, volleys and touch shots were dead. No exception with SPPP. Totally devoid of feel and feedback even with full proportional stringing. So dead I kept volleying easy shots into the net or out long!
- Long-drawn points were disadvantageous to me since I realized the string and racket flex timings were totally out. Neither could I rely on topspin as I either could not load the strings, or I ended up hitting too clean on the sweetspot. Again, the result was either into the net or out long.
- I found it was very difficult to play with this setup. But keep in mind, I have always preferred syn gut.

Overall
- To me, the greatest strength of this string was also it's worst flaw: tension holding.
- I doubt it was the ingredients. Highly suspect this string was heavily prestretched in the factory, hence its impeccable tension stability, both overnight after stringing and after the initial session of play.
- If it was indeed prestretched, it should have been indicated on the packaging. Then I would have strung this completely differently. Discovering, or suspecting this after stringing it up was very disappointing.
- That said, all was not lost. To those very hard-hitters looking for tension stable polys, or to tame very powerful stiff rackets, this string would be an exceptionally good fit. Just a straight-up full bed somewhere in the mid-40s to mid-50s lbs would suffice.
- If I were to try this string again, I would probably go for 40 lbs or less. That's how meek my swing is!