Very disjointed kind of night - seemed like I was just out of sync and most everything didn't go smoothly, but I recorded a few videos anyway of a ball machine session testing Sapphire.
First, some forehands. I cut this video as someone fell on the next court with a yelp. Same as the previous hit in that the string has liveliness and is plush, with good pocketing sensation. But there were some changes that became more obvious when I finished with about 20 minutes of live hitting which I didn't record, and that is that the launch angle is starting to decrease. You can see that many of those shots have good shape and net clearance, but there were also a few that just barely cleared the net. It seems that unless I caught the ball just perfectly, it was starting to lose that bite that gave me the higher launch angle. Apologies for not realizing that my phone was aimed way off to the side. Like I said, I just felt a bit out of sync today.
Volleys were point and shoot. The plushness doesn't create a control issue and the stringbed is firm enough and insensitive enough to incoming spin to make me feel very confident I can hit smaller targets. I tend to volley pretty flat, especially on the forehand, and here the round string gives exactly what is put into it. Control is very good to excellent, and I hit some drop volleys at the end that despite the relatively high power level of this string, was able to absorb the ball speed with excellent directional control. And the out of sync thing continues as I hit the tripod with one of my volleys, which knocked the phone over to an angle that I didn't notice.
Last, some backhands. I recorded this near the end of my ball machine session and right before some live hitting, and at least I didn't hit the tripod and break my phone. I was starting to notice the ball coming off the stringbed a little low but thought it was just due to the really inconsistent, worn, and dead ball machine balls. What I notice on my backhand is that underspin shots are floatier and have less ball speed. They don't have the same spin rate even though I'm trying to put quite a bit of spin with the shots that I hit, and I felt like I needed to try to heavily spin the ball in order to not have the ball float high and slow. I don't know that I'd be able to consistently try to spin the ball this heavily and not make a lot of unforced errors, but my regular backhand slice probably clears the net by an extra foot and then sits up after the bounce.
In the live hitting afterwards, it is pretty clear that the launch angle had come down from what I experienced yesterday. It wasn't due to tension loss. After I got home, I measured only another 0.4 pound loss according to RacquetTune. The strings are now notched - there is a sharp click moving the crosses and the mains take more force to slide. Power levels, the pocketing feel, and comfort levels are unchanged.
I hit with the Evolution and Confidential racquets today also. Despite the loss of that bit of launch angle with the Sapphire, it is still higher than with Evolution. On similar shots, I have about a foot more net clearance with Sapphire, and what seems like maybe a couple of MPH less ball speed with Evolution. Underspin backhands have a more biting trajectory with Evolution than Sapphire, even though spin production feels roughly similar between the two.
Pulling out the Confidential showed how much difference there now is. The fresh Confidential gave me between 1-2 feet of higher net clearance on the same swing than with Sapphire, and the ball visibly has more spin as it dives towards the court more strongly and bounces higher. Slices really hug the net and shoot through the court with a very low bounce. When I try to increase the amount of topspin, I get a strong sensation of the strings biting into the felt on the ball, and that gives me a lot of confidence that Confidential will do what I am asking of it. I don't get that same feeling from either Evolution or Sapphire.
Both Evolution and Confidential are more harsh than Sapphire. Evolution feels a bit tinny, with a high frequency, post-impact vibration that Confidential doesn't have. Confidential feels slightly more jarring than Evolution when missing high on the stringbed and has a stronger pocketing feel. Power levels are lowest with Evolution, slightly higher with Confidential, and then a big jump in the liveliness feel to Sapphire.
I think because I'm using a 73 RA racket, that it puts greater stress on the strings because the frame is relatively unyielding. This magnifies changes in the stringbed response as the string intersections notch and as the material loses elasticity and tension. I'm curious if others also notice the same changes I've seen.
