The spec of A5 is more even balanced but when played alongside the JS10 it's very similar. The new Ubers such as F2.1 are far more head heavy than JS10 but for me have more feedback than the previous Uber range.
But wouldn't the F3.1 be the better choice when coming from a very stiff JS10? And without having played with a JS10 yet, I felt it was really similar to my P8 in so many ways. It's a compact head, it's the same hole/stringing pattern, it's quite stiff, .... however, while being 1 to 2g heavier overall [3U vs. 3U; not the same, but quite similar grip setup, same string], the JS10 had about 2g less headweight. I admit, but if going for a 4U P8, the difference should be less and in many other ways other than weight and weight distribution, those rackets are very similar.... So if anybody is looking for a head heavier JS10, I can't stop to think about the P8. Now.... i get different information here, loving the balance, but wanting more power is tricky. Oversimplifying: More flex will help to get more easy power, while more stiffness will raise the power ceiling. Overall, the power comes from the player, the racket is just a tool. If you like the stiffness and the compact head of the JS10, but want "more" power, I think the P8 (maybe as 4U) would be a great option to try. If you want to stick to the balance of the JS10, but you want "easier power", listen to Dave. However, having had some dry swings with the JS10, I find it hard to believe that the Adidas Kalkül A3 (that I think I know quite well by now) can offer more power.
The JS10 is head light to mid balanced and a fast frame, the P8 is head heavy and not as fast a frame. They feel completely different when using side by side. I switched between JS10, A3 and A5 one after the other around 3 weeks ago without any issue. The JS10 was the fastest and most head light, closely followed by A5, the A3 gave the easiest access to the power and was marginally the slowest.
The main factor for being a "fast frame" is most likely the size of a racket's head and that's (almost) identical for the JS10 and P8. My impression (without a shuttle, but side by side) made me feel like exactly that, just that the P8 felt head heavy and the JS10 felt evenly balanced. Considering that the JS10 was heavier at the same time, I can accept that it's supposed to be head light. With 2g less weight in the head, sure, it does feel a lot faster, but that doesn't make the "frame" any faster or slower. That's just mass and physics. For the head weight it has, the P8 is fast! The A3 is supposed to be very slightly stiffer than the A5 and that also is the impression I got when reading other comments/reviews on them. The more flex with more headweight is what scared me away from trying the A5.
For me, the cross section and overall frame thickness has far more to do with a fast frame. That's why BS frames are seen as some of the fastest despite having a larger head than some other rackets. The P8 has a very thick frame in places which is great for rigitidy/stability but makes it slower through the air. The P8 is fast considering its head weight and the frame thickness but can't be compared to BS, JS or AS frames in terms of speed in my opinion. The spec says the A5 should have a little more flex than the A3 but due to the balance and differences in the carbon 30T/24T, it doesn't feel like that when used.
I think the discussion "head size vs. frame shape" is a very difficult one because it is very, very complicated to get some evidence in that regard. We have to also add the fact that air resistance mostly comes into play as soon as the head is moving fast, so basically plays a minor role on defence blocks (which are usually mentioned in line with the racket being "fast"). And there we would simply be back at the good old head/swing weight being the dominant factor. But let's go back a step there. First of all - the JS10 is a unique racket. There simply isn't any other racket that has that typical JS10-feel whilst simply hitting harder on smashes. Physics are physics. If you wanted to add more oompph, you would have to add head weight and thus making the racket slower. You cannot compensate extra weight with even the best and most highly sophisticated racket design wizardry. Looking past the weight, what makes the JS10 so special? IMO it's the compact head, combined with a very stiff shaft and a relatively slim frame. That combination does not exist in the Adidas line-up, so if you want to go with Adidas, you will have to make some sort of compromise before you even decide on weight and balance. P8: compact head, very stiff shaft but a thicker frame. And the mentioned ~2 g more head weight (if you compare the 4U JS10 with the 3U P8). The thicker frame imo puts it ahead of the JS10 in terms of torsion stability and feel, has clearly more ooomph behind the big swing smashes but inevitable is slower. I haven't played the A5 yet, but simply going by specs and impressions by others. A5: regular sized head (more user friendly!), slightly less stiff shaft, slightly more head weight, and yet again a more bulky frame. So in theory, this combination should make it more user friendly in every department but again, it will not be as fast and snappy as the JS10. We can discuss endlessly about minor things but bottom line, each racket will feel completely different from the others. I also bought a JS12 when it came out with the same expectations that you had. It was on of the biggest disappointments ever and imo didn't deliver anything it was supposed to on paper. So in the end, buying a racket without testing it before always is like buying a pig in a poke.
Great post! I totally agree with what you said about each racket having its own characteristics and everyone having there own opinion on frame speed and characteristics. Im offering my findings after trying hundreds of rackets and finding that A5 feels very similar to JS10 side by side despite differences in the spec on paper. Out of the Adidas range, if @taz88 wants something similar to JS10 then I suggest A5, if they want a little more power then I think the A3 fits the bill best.
This is a great post! Your experiences with the JS10 mirror mine, even the assumption the JS12 would be a sure upgrade, made me smile... For me the feel & feedback of a racket is the no1 priority & so far I've yet to try anything better than the JS10. I guess I should be content but you always wonder if a different racket would improve your game, give you that monster smash without compromise.. A5 & A3 both sound interesting so may give them a try. Thanks @Dave1011 & others for their advice..
Pretty sure that's 3U vs 3U, at least the ones I compared. I have to admit that I didn't check what it said on the JS10, but it was heavier than all my 3U P8, very little cushion wrap and an overgrip on wood. I cannot see how Victor could call that 4U.
The struggle is real, I'm more than guilty of hunting the impossible myself. Please keep us updated regarding that A3 and A5, I'm really curious to hear your impressions. Oh, and btw the JS10 still has a constant place in my bag, even after buying at least 10 different rackets since I played the JS10 as my main racket. It's like herpes... the itch just never goes away completely.
Most JS10s you see are 4Us I think. I've owned a 3U once but it was only 0.5 g heavier in the head than the 4U, so with the usual big Victor tolerances, the difference to the P8 could easily be in a range of 1 to 2.5 g. If I remember correctly, my JS10 4U is about 1.5 g lighter than the P8 3U but I'll have to re-measure both tomorrow to be sure.
Yeah the JS10 was initially 4u and 5u only, most people bought the 4u. 3u MYP and KRP versions were later introduced and then a commercial 3u version.
And here we go - both rackets with same string and grip setup. JS10 (4U): P8 (3U): The difference in head weight is only around 1.3 g. The P8 is a borderline 4U though. If you get a light 4U there and/or remove the side grommet strips, you should end up very, very close to the JS10 head weight.
The JS10 I had to compare was significantly heavier, but didn't carry that much more head weight. Thank you!
Welcome to the world of Victor tolerances. Mine is a true first gen JS10 (in fact one of the first batches that arrived in Germany) and the racket has seen a number of slight changes in the later production years (no more SharkTec pimples, no more "pyrofil"...). The JS10Q then ended up being a different racket imo.
EVERY JS10 iteration has had sinking grommet issues. Mine shows slight sinking on a couple of holes, but that didn't impact the performance. And it hasn't gotten any worst since I put in those big T shaped grommets in the affected holes.