Babolat AeroPro Drive (2007)

I'm late to the Babolat party...

On many occasions, I tried different versions of the APD on court. It is such a popular racket that someone would surely show up with it.

However, this time I set aside my own and hit exclusively with the 2007 APD for about 20+ hours. Both to test the racket and some exotic strings which would remain unknown.

While the specs (link) may claim a total weight of about 320 grams with 324 swingweight, the one I tested was 330 grams strung and gripped. Swingweight was very close to 330.

Not a big deal to me since I am no stranger to heavy sticks. (link)

Strangely, this APD felt slow and unwieldy. My timing was late. Everything including serves, serve returns and forehands. I could not understand it. It felt like I just finished the ironman triathlon minutes before playing tennis.

Naturally, I ended up arming/muscling the racket through. But I was still late. And the power threw my control haywire. I could not control the ball depth nor direction!

After struggling like a clown, my NTRP 4.5+ friend, a decade-long APD user, chuckled and pointed out the "secret tip" to me...

"It's a swinger's stick... try standing further back..." he said. (link)

Ahhh....! Then I got it! My forehand and backhand started falling in place. The loud "thwack" of the ball impact on the full poly stringbed sounded and the spin started kicking. 

Serves took a little longer to get in tune as I had to adjust my toss and timing so I could "throw" the racket at the ball. 

Once attuned, I aced a few second serves. The spin turned the ball down when all four of us thought it was flying long. Then kicked forward to catch the receiver totally off-guard. Certainly not something I normally delivered.

I became very impressed by the APD. Just loosen up, grip down, start the foreward swing a tad earlier, and enjoy letting the release of the wrist-hinge slap through the ball. So effortless!

As long as I was early with both footwork and racket prep, sweetspot and near-sweetspot ball impacts felt plush and comfy. There was no hint of any frame stiffness at all. (Of course, the secret string played a part!!!)

Conversely, when I was late, like under attack or read the ball wrongly, the APD was very demanding to move. 

Like I had stacked too many plates on the barbell. Attempts to direct the racket at this stage meant a stiffening of the grip pressure. This engages the forearm and biceps while locking up the wrist. 

Instinctive, but very wrong and deadly move!

The punishment for this was the full, jarring impact of the ball landing on the hand, wrist, elbow or shoulder. Especially with the lack of racket momentum to buffer the incoming "punch" from the heavy ball.

It was nasty!

Another issue was power.

When I was in full balance and contacted out front, I could unleash the full swing, load the stringbed well, and let the topspin keep the ball in the court. When late, the power was too much.

To curb that power, many tightened up the tension. Or selected a much stiffer low-powered string. Then they ended up "arming" the ball even more. 

Disastrously, that was how the APD destroyed several of my former playing partners' elbows.

The polarization of weight in the APD is so deceptive. It fooled me and many into thinking it was fast and easy to maneuver. But it is not.

Don't be deceived. In my opinion, the APD is a player's frame. Beginners like it for it's easy power so learning tennis becomes faster. 

However, it is a very demanding frame that expects good read of the ball, fast footwork and very early swing prep. Without which, it could cause some serious havoc with the player's arm.

Now I understand why many deemed this the indisputable "arm killer".

Play safe!




     

"Annual Pilgrimage" with Budget Natural Gut

Over Christmas, after the gift exchanges, a friend gave a set of budget natural gut to me. He received it but did not care for it.

I happily accepted it and offered to post my review. 

It was in a transparent plastic bag. No names nor labels. Just a type-written sticker pasted over the sealed bag, saying "Naturel Gut".

The gut looks very smooth and had a translucent glow, something like Klip and Babolat VS. Other than the packaging, it does not look like budget stuff to me.

After clearing most of the backlog of work and stringing requests, I thought maybe it's time for my annual pilgrimage with the ProStaff 6.0 again... (link1)(link2)(link3)...

All the standard steps were strictly adhered to. Things like cleaning clamps, prestretching gut to remove coil memory, checking grommets for sharp edges, etc.

However, the natural gut snapped during tensioning. I had only completed 6 mains when it happened. All at a modest tension of 55 lbs.

Fortunately, the snap point still left me enough gut to fill only the centre mains in the ProStaff 6.0, like in the "Lendl Pattern" (link).

So I filled the outer perimeter with poly first, then started on the mains very very carefully and slowly...

But just when I was tensioning the second last main string, the natural gut snapped again! Somehow, the first snap point triggered a second snap point in the natural gut!!!

Of the three snaps so far, none occurred at the clamps.

Could installing budget natural gut into the ProStaff 6.0 be disrespectful and blasphemous? Was that why the gut kept snapping? Because the ProStaff 6.0 rejected it?

After one hour, two failed attempts, with three snap points, I was beginning to understand why my friend was so "generous" to give me that pack. 

Since I had gone so far, I decided to continue with the remaining half-set in the pack and be done with it. Successful or not!

At last! 

Ended up with so many short pieces of snapped natural gut! 

It played very well, but I doubt I would use these budget stuff again. Really a waste of time!




     

Budget Strings?

The lure of fresh strings is difficult to resist. If not for its price, everyone would follow the restringing patterns of their favourite players on tour.

When sufficient unfulfilled needs arise, a business opportunity comes by. So budget strings popped up, some at merely ¼ or less the price of original brand names they claim to replicate.

Since I have yet to figure out how to grow money on trees, I jumped on the bandwagon too. Then got off. And on. And off. Multiple times. (No brands nor models will be mentioned here)

There are multitudes who "swear by" the quality of these strings. And probably an equal number who threw out unused reels.

So far, I have succumbed to cheap natural guts, syn guts, polys and kevlar. Out of about nine different strings I tried (many multiple times), I thought a few polys were not bad, playing almost 70-80% similar to the real deal. 

Usually, two similar sticks were strung, one with original strings, one dud. They were rotated during play every fifteen minutes. A single new can of balls was used.

At 15 minutes, both were almost indistinguishable. At 30 minutes, significant tension loss started creeping in. At 45 minutes, control and spin departed to string heaven. Budget price for budget durability too?

The kevlar did not feel like kevlar to me. More like garden wire. (link) The syn gut was completely devoid of any feel or feedback. It gave me the impression it was strung with coaxial cable.

Buying and stringing the budget natural gut was like playing russian roulette. One batch was kinked with white fold-lines straight out the package. Could have been the shipping, so after some negotiation, I settled on 50% price for a replacement and some freebies.

Nevertheless, I strung it up at 52 lbs. And it snapped in the bag overnight, right at the kinked spot. The replacement arrived in better shape. However, my gripe was the huge variability in gauge from start to end. I think it ranged between a 15g to 17g. And it was uncoated.

As it is, my tennis game is pathetic enough. Add to that my Mr Bean styled footwork is enough to make anyone collapse in laughter. Unless I'm bent on working towards ntrp 0.0, I would be giving all these budget strings a miss.

Or I could save them for competitors who beat the crap out of me everytime...

Difficulties of Hybriding Strings

Many asked for recommendations how to hybrid and pair strings. 

Most commonly:
- What tensions for mains and crosses? Any differentials?
- Which string for mains? 
- Which for crosses? 
- What gauge?
- Prestretch?

Personally, I do not enjoy hybrids. (I have even tried tri-brids and quad-brids!) No matter what I pair together - kevlar, syn gut, multifilament, natural gut, soft poly, stiff poly, fishing line, steel wire or grass trimmer line, it was extremely difficult to balance them well.

Inevitably, one string would dominate over the other. Usually, the feel and playing characteristics of the mains prevail. Once in a while, the crosses. 

I am far from solving this puzzle, but I believe it has something to do with how the strings behave at different tensions.

When pulled to 55 lbs, the amount of total stretch observed in the following strings were:
- natural gut 6~7%
- synthetic gut 9~10%
- multifilament 10~12%
- poly 3~4%
- kevlar 1~2% 

The numbers were in a range due to different batches and brands. 

These same strings, when pulled an extra 10 lbs, bringing them to 65 lbs, yielded an incremental stretch of:
- natural gut 0.4~0.7%
- synthetic gut 0.8~1.1%
- multifilament 0.5~1.2%
- poly 0.1~0.3%
- kevlar 0% 

The conventional wisdom is to string the softer string a couple pounds tighter. Using poly/syn gut at 53/55 lbs for example, would see them stretch about 3.5% and 9.5% respectively when strung.

However, during ball impact, the amount of additional poly stretch available is less than half that of the syn gut. Even though the strings are inter-weaved together, hard impacts bring the poly into deformation territories. 

In other words, poly gets stretched beyond its elastic range and loses tension. Over time, the feel of the syn gut increases. (see "Impact Loss" in table below)

And that's only assuming one plays with the racket immediately off the stringing machine. 

(from Tennis Warehouse University String Performance Database link)

When allowed to rest from being strung at 51 lbs each, the "Actual Pre-Impact Tension" has already dropped to 30/39 lbs! This differential would only get wider with every ball hit.

Having established this, then how about we string poly higher instead? Would that help to compensate for its larger pre-impact tension loss compared to syn gut?

Probably yes. But only for a while before impact tension loss brings down the tension again. How fast this happens depends on how tightly strung it initially was and how hard one hits the ball.

Another often overlooked factor is string gauge while pairing. Many choose the same gauge for hybrids, typically 17g or about 1.25mm.

Using the same example of poly/syn gut earlier, from my own measurements, the 1.25/1.25 mm combination would thin out to about 1.20/1.13 mm. 

Below pic shows a 1.40mm syn gut became 1.25mm strung.

Below shows a 1.25mm syn gut thin to 1.10mm strung.

An easy way to calculate this diameter change would be to use the percentage stretch as a proxy. A 1.25mm string with 10% stretch, usually becomes 1.13mm (0.90 x 1.25) strung.

Simple engineering dictates, the thicker the material, the stronger the support. This could be another factor why the poly mains dominate when paired with syn gut in the same gauge. Well, but many people like it, so it's their choice.

Perhaps after reading this, one could start deducing why Federer is touted to be using 1.30mm gut mains and 1.25mm poly crosses:
0.93 x 1.30 = 1.209 mm
0.96 x 1.25 = 1.200 mm

The same gauge combination of 16G gut and 16L poly for Serena Williams as well? (link) And Sharapova? (link) And Nishikori? (link)

That said, my personal preference is still a full bed of the same string. Primarily for its ease of adjustment and consistency after play. If I were to cut strings out after every hour of play, then it might change.

After all, according to the Luxilon String Analysis at the 2013 US Open (link, refer pg 6-10), more than 70% of the competitors used the SAME STRING in both mains and crosses. 

Special thanks to Irvin for highlighting that report. (link)

Different Generations of Poly Strings

Despite having been around for about three decades now, many still seem to have misconceptions about poly strings. 

From its infant days, poly has come a very long way. Broadly speaking, we are now in the fourth generation of poly strings.

Without referring to specific brands or models, the first generation poly string was simply slick, stiff and dead. Nothing else.

Elasticity was so low that every ball impact took some tension off through string deformation. String life was so pathetic that it was probably better monitored by the number of shots one hit, rather than by time used.

While the spin was hugely rewarding, the stiffness must have affected quite a few players. As a result, a second generation of poly was born.

Additives were added to soften the string and the term co-poly surfaced. When strung within a specific tension range, from about the mid-40s to low-50s lbs, a higher level of comfort was achieved through greater elasticity. 

Within this range, tension holding also improved. However, when strung below or above, it still played as boardy and stiff as the first generation.

I believe it was from this generation of poly that caused many misconceptions about poly's useful tension range, up till today.

The third generation poly was heavily marketed with more "bite". That was when shaped co-polys came aboard. Five-sided pentagonals, hexagonals, spirals, twisted and fused, and many with rough edges became wildly popular. Comfort improved further.

The most popular fourth generation poly string now is Luxilon 4G. Aptly named, as "4G" simply refers to fourth generation. Tension holding and comfort were touted to be "uncommon for a poly".

Somewhere around the third or fourth iteration, the useful tension range widened tremendously. Many reported great results from as low as 20+ lbs (link), to as high as 90 lbs! Yes, with full poly!

Personally, I have tested quite a few between 30 to 70 lbs. Surprisingly, at either 30, or 70 lbs in the same racket, it played almost equally boardy! But the one with lower tension loosened up much more rapidly, whereas the tighter strung took about an hour to "break-in" before playing well. 

I could not find much difference in the amount of spin between the four generations. Variances were only on comfort and tension holding.

Whichever generation of poly it is, keep in mind it was introduced solely to generate tons of spin. To achieve that, it has to be made very slick and very stiff to snap back effectively. Slick and soft would not work as well for spin.

As a result, poly demands a strong loading to play well. And that could mean very long loopy full swings, or rackets with high swingweights and open string patterns. 

Tennis balls that are a little heavier, have high bounce and are "hard like rocks" for natural gut or synthetic gut could also possibly help with the string loading required. Just be wary of your own shoulder, elbow, arm or wrist tolerances.

Soft Shaped-Poly Hybrid Test in MFil300

Quite a few of my playing partners use this string and shared good reviews. When I tried their rackets, I was pleasantly surprised at how soft, yet firm this poly played.

A friend whom I string for asked if anything could be done to add a little more "finesse" and pocketing for touch shots like volleys or mid-court put aways. A little more power would be nice too.

From his reel, he cut out about 24 metres and asked me to "play around" with them, then share my findings. To prevent bianess, brand was withheld.

Some simple string test results I did revealed interesting differences from earlier poly strings. 

This third/fourth generation poly string:
- has a much softer material composition that could be dented with my fingernails with some effort,
- appears to have a stiff inner core,
- has an inelastic elongation component only about half of some of my second generation poly strings,
- has its overall elasticity reduced slightly as well.

Since he wanted more pocketing and touch, the best way was to hybrid with a softer string. In this case, a syn gut in the crosses.

With its soft outer layer (not a coating), the poly was easy to string compared with traditional polys. Touch wise, it reminded me a little of pvc coated garden wire.

Playtest:
- Even though we played about 48 hours after stringing, the first few shots felt a little uncomfortable. A muted kind.
- It was not harsh. There was definitely some "cushioning" in the stringbed but insufficient. Somewhat like jogging on a concrete path with a very old pair of running shoes?
- Since I was not a poly lover, I handed it over to another partner to do the breaking-in, and to let me know his opinion only after the entire session.
- After about an hour, I resumed testing.
- The "harshness" was almost completely gone. It started to feel more like a fullbed of stiff and crisp syn gut.
- The "loading" of this hybrid was interesting. The stringbed felt tight for both low and high powered shots. 
- Taps and blocks sometimes felt like it was not enough to load the string. That was fair. Yet, full swings conveyed a "not enough pocketing" kind of feedback sometimes.
- Middle of the range shots produced the best results. Those 60-70% smooth swings elicited soft, controlled feedback with spinny balls. It was very enjoyable and made me want to just rally that way forever.
- Low powered shots were slightly lower powered than other polys. All-out swings were also lower powered than other polys. Smooth swings yielded the closest to "normal" kind of power compared to other strings.
- This advantage was, power control could be delegated to the stringbed with less variation in our swings. We could swing away more freely.
- It also made me think, could this be the string company's attempt to market poly to "softer hitters"?

DIY Textured Strings?

Many of the newer polys are shaped or textured, claiming it would increase bite and spin.

Despite many polys I've tested, "The One" remains elusive. But the idea of a rough texture increasing spin through higher friction appeals to me. (link)

Since I no longer break strings like I used to, I cut them out after about 8-10 hours, or when they've lost their mojo.

Instead of cutting out one that's due, I thought I'll rough it up as an experiment.

Even with a 60 grit, sandpaper was too smooth. I wanted it REALLY rough! So the bastard file was deployed.

It was so rough it was impossible to draw the stringbed against the back of my hand. Perhaps a really sadistic person could do that, but I couldn't. Neither my partner.

How rough? Just think of a grating tool...

To preserve some durability, only one side of the stringbed was filed. The other was left untouched as a comparison.


Playtest:
- Before and after roughing the strings, I measured the stringbed frequency. It was the same. So tension was a non-factor, even after play.
- Within the first few hits, it was obvious that ball feel was A LOT better on the rough side. The difference was something like hitting with a 18g string versus a 16g.
- Another surprising find was an improvement in directional control.
- Even when hitting totally flat, it felt so much easier to aim and direct the ball. 
- Comparing both sides, the smooth side felt slippery and that the ball was skidding a little across the strings during impact! Without a high speed camera, there was no way for me to verify that, it just felt that way to me.
- To ensure the greater accuracy was not mere psychology, I got my partner to feed me balls while I aimed at targets I usually found challenging. Five shots each were attempted with each side of the stringbed, alternating at every shot. The result was telling!
- I got my partner to try while I fed him easy balls, and he shared exactly the same sentiments.
- With the extra ball-to-string friction, all kinds of spin improved across all strokes, including serves.
- This extra bite on the ball was easily seen after less than ten strokes! The tennis ball fluffed up like a pom pom ball!
- The stringbed pic is below.

- Keep in mind, this stringbed was already used for about 9 hours before this. It was dead enough for me to want to cut it out.
- If you wish to test it, go easy on the roughing process. I snapped the earlier two attempts, this was the third.
- Even this snapped overnight after about an hour of play.

Strings Quality Control

A few friends whom I string for regularly usually keeps a reel or two with me.

Right after playing with a fresh stringjob, this friend called and asked if I had changed anything, or pranked him (link).

I assured him I did not and did exactly what he instructed. But he claimed the strings played very differently.

My stringing mentor used to say, "When in doubt, check EVERYTHING!" So I did:
- Correct strings used --> ok
- Racket dimensions before and after stringing --> ok
- Clamps slippage --> ok
- Dropweight tension alignment --> ok
- Tension settings --> ok

He claimed the strings played a little dead, like it was over-tensioned.

So I asked:
- Did he leave the newly strung racket in a parked car?
- Did he change to a different brand of tennis balls?
- Was he playing in a different tennis court?
- Was he playing with different partners?

Strangely, everything was the same. Even his regular buddies commented how poorly he delivered all his shots that session!

Then I checked the strings. It was from a new reel he just bought from a very reputable online shop, exactly the same source as the previous reel. So it seemed legit.

Everything appeared in order when comparing the logos, fonts, packaging, string colour, texture, etc.

Out of curiousity, I measured the string diameter and found it 0.03mm thinner than the leftovers from the previous reel! Aha!

Samples of both were cut out, labelled carefully and tested for its elongation properties on the stringing machine, like this.

Then the answer came!

At the same tension, both fresh pieces of string differed in their stretch by almost 20%. This is a huge difference by itself, and together with the 0.03mm thinner diameter, it could totally be passed off as an another string! 

Either the QC was off, or the string factory had labelled and packaged the strings wrongly. Or the formula was tweaked! 

If you check online forums, this seemed to happen once in a while. Reports of different coloured strings playing differently were more common.

To save on shipping, my friend bought 3 reels of this premium string. The total amount spent was more than enough to pay for three brand new Babolat rackets! 

Thankfully, after sending photos of the diameter discrepancy, the shop offered to grant a full refund via credits, less shipping. The downside was, the 3 reels must be shipped back at our costs.

As for me, it was a great relief to be vindicated.

More Power More Spin!

While I took a two decades break away from tennis, many of my old buddies did not.

I tracked down another old mate recently, hoping to catch up on some tennis. Unfortunately, it's his turn away from tennis now. Not a voluntary decision though. 

He developed severe tennis elbow and wrist pain around the ulnar area (link). Most days, he cannot even use his master hand to drink his morning coffee. It is disheartening to see him look seemingly healthy but suffering from such pains.

He shared how his quest for "more power more spin" drove him to stiffer and stiffer frames strung tightly with full poly. But he forgot he was aging!

Just a few years ago, he was the typical profile of many tennis players today who:
- wants more spin,
- wants more power,
- uses light & very stiff frames,
- strings too tight (above 50s) with full poly, and
- restrings his rackets only every few months.

But synthetic gut can generate heaps of spin too! And add plenty of comfort along the way!

To test that, I invited a few current tennis buddies, who are heavy spinners to try syn gut. Sadly, most declined, claiming syn gut is so very passe...

C and PK were two who matched the typical profile and accepted the blind test. (PK admitted that the last he used syn gut was a few years ago.) 

All they know, were their rackets were strung with syn gut. Nothing else was communicated.

Both were asked to track amounts of spin, comfort, control, power & durability compared to their usual full poly strings.

Here's one stiff frame I restrung with full syn gut...

When I cut the poly, there was minimal snap. The string stayed close together with only a tiny gap. To me, that was an indication either the poly was strung too tight or the string was dead from use.

Another clear sign was the very severe notching on the mains. To have continued playing with this was akin to committing arm suicide.

A modified proportional stringing method was used to better distribute the string tension around the stringbed. That helps to add ball cushioning and spin.

Playtest:
- Over the March 29-30 weekend, both C and PK clocked 4 and 5 hours of play respectively with the fullbed syn gut.
- While their ages may be apart by about a decade, their feedbacks were generally similar.
- Note that I did not watch nor play with either of them.
- I grouped their findings for ease of reading below...

Initial impressions
- Both thought the all black syn gut looked like full poly.
- C was completely blown away by how comfortable the syn gut played. 
- Barely 15 minutes into his rally with his usual buddies, C could no longer contain himself and let the cat out of the bag. His partners then took turns trying his racket and declared it "unusually advantageous".

Comfort
- Unanimously very good.

Spin
- C does not normally hit with heavy topspin as he felt it was an inefficient stroke and took away too much of his power. However, this setup provided very easy access to the spin he had wanted. He pulled off a lot of slice winners and "quite a few heavy topspin shots easily".
- I found PK's feedback on spin a little contradictory, so I thought I'll just quote what he wrote:

"Spin was normal but I find that I needed less power to generate the spin. I used new US open balls (US version). The whole racket was filled with fur."

"I felt my slices was awesome today as most of it went in with a lot of spin."

"This is the first time I have seen ball fur on the strings. Never on any polys I used even with hexagon shape strings."

"Tried to use 100% full swing. I noticed that if I hit prematurely, the ball files out. Spin was good only when the contact of the ball was during the brushing motion. If I can get my timing correct, my shots will be really deadly."

I play lousy tennis compared to C and PK, but from PK's words above, it seemed like there was indeed access to a lot of spin. However, some stroke or timing adjustments may be needed compared to their regular full poly setup. Or, was PK too excited to whip the ball that he was hitting early?

Control
- C did not notice any drop in control and accuracy. 
- However, C felt that the comfort of the syn gut stringbed gave him a lot more confidence to execute difficult shots without the fear of "stinging pain" on off-centred ball contacts. If this was taken into consideration, he felt control improved.
- Another observation by C was a huge increase in the sweetspot size. He felt he miss-hit less balls with this setup.
- PK commented:

"Control was a little off today maybe because I was not used to the strings. I could not hit hard with this setup as I could feel the trampoline effect."

"I felt control was a little off after 3rd hr of playing."

Power 
- From what I heard and read, there was an abundance of power experienced by both. Only PK used the word "trampoline" once. (Note: PK is in his mid-30s, about 1.8m tall, fit, muscular and very athletic)

Durability
- There was no string breakages, no mention of string movement or notching. So I deduced it either did not happen or it was so minimal it did not bother them.
- Since I did not get to meet them, I could not measure the frequency drop after play as well.


After their feedback, I expressed thanks to both for their willingness to risk messing up their strokes to try this setup. My only objective was to prove that syn gut CAN offer heavy spin with comfort. From what I have read, I am satisfied.

Unknown Poly String Test

After reading "String Death & A Little History on Poly Strings..." (link), an acquaintance, CK, asked if I could help him test a poly string. 

He bought a reel of that poly based on good reviews but has never liked it. On the contrary, his experience was very different from what he read. 

CK was worried if international shipping could have damaged the string through heat, humidity or other stresses. I assured him not. And poly probably has a long enough shelf life (unstrung) to remain playable even for his great great great grandchildren!

Primarily, CK wanted to know: 
(1) what is the "useful tension range" of the poly, and 
(2) what are my experiences after using it.

He handed me two coils of about 12 metres each in an unmarked envelope. I have asked not to be told what brand or gauge to remain unbiased.

According to his peers, CK is about a ntrp 4.0 all courter. He uses a 100 sq inch racket with 16x19 string pattern. The closest similar configuration I have is my Wilson Hammer 5.8. As mine was just restrung, CK agreed to wait until my strings are worn before I test his strings.

Physical attributes:
- It is a black coloured poly.
- Looks hexagonally shaped.

- When I tried bending and twisting a short end of the string, it felt very firm and stiff. To me, that was the first hint it could be a stiff poly.
- The string measured very close to 1.15mm on my gauge. It was consistent at ten random spots throughout the entire coil. I'm amazed as there are not many polys this thin.

I chose a poly/syn gut hybrid first, to test how it would perform in just the mains. Also, I like to start from extreme ends then work back towards the mean. So tension would be 55/53 lbs.

While stringing, I weaved a few crosses with the same piece of poly to get a feel of how stiff it was, and also to understand how easy it was to notch. The mains sliding action while playing is a common cause of notching and breakage. This poly is easily notched.

On its own, it can be difficult to assess how much spin it has. So, I always bring a familiar racket and strings setup as a benchmark. It's the Yamaha again.

Playtest observations:
- This is a stiff and low-powered poly. It played so much boardier than almost every stiff poly I've tried.
- The string did not yield much. Surprisingly, it felt very similar to dead poly - flat and lifeless. 
- I thought it could be still "too fresh" from stringing, so I hit some hard and flat rally shots with us standing about 2 metres behind the baseline to try to "break-in" the strings. Still no change.
- Spin was pathetic. A poor performance considering it is hex-shaped. Even when I got my partner to feed me easy balls, I could not get my topspin to kick. Many flew out. I am beginning to understand CK's disappointment with this premium string.
- I moved my dampener to 12 o'clock. That added about 10 swingweight points to my plowthrough. Still dead.
- After an hour of hits, it still felt boardy. Any attempts to serve with heavy spin were futile. There wasn't much string movement nor ball fur stuck on the strings either.

- Compare that with the ball fur on the Yamaha with very well worn full bed syn gut below.

- Incidentally, I took a very close look at the Yamaha's syn gut and realised that the main strings' sliding action has "abraded" the cross strings and made them flat instead of round! What do you think that'll do for spin? Easier to slide?

- I'll give this poly some time to settle-in before thinking of my next course of action.

Note:
I will eventually know what brand this string is, but I will not be posting any details about the strings here.

19Mar2014 update:
- I think my strokes are too weak to soften the stringbed, so I got a big hitting poly-loving friend to play with this racket for an hour. Strangely, he loved it.
- I tracked the stringbed frequency. A day after stringing, it dropped about 18Hz. After an hour of play, dropped 13Hz. After my friend hit for an hour, dropped 7Hz. Total drop is only 38Hz so far, and at a declining rate of loss!
- This poly has very impressive tension holding and stability! 55 lbs was definitely way too high!



26Mar2014 update:
- While I enjoy string testing and exploring fanciful string patterns, my old body cannot withstand the rigours of daily tennis anymore. So I delegated this poly test to another poly loving partner of mine. I will still hit with it but only for a short while, and intermittently.
- I cut out the previous setup and restrung at 45/43 lbs. Ten pounds is a significant drop, I think.
- Through googling, I realised that there are actually factory pre-stretched poly strings for sale. To me, this defies logic. There is so little elasticity in poly, and most are already over-tensioning poly. And now factory pre-stretched? I suspect this mystery string could be one.
- Not surprisingly, after about 90 minutes of play, this friend remarked that the string played almost similar to the previous setup at 55/53 lbs! Huh? Could be a first clue this string was pre-stretched.
- As usual, I'll let the stringbed settle and try it out myself.


28Mar14 update:
- I played an hour with this setup. Perhaps my friend has already broken-in the string for me, but it felt so much softer and responsive today compared to previously.
- Spin was more than at 55 lbs but it did not wow me nor my partner. 
- Comfort improved a lot. Power was still low.
- After a total of about 3 hours of hits, tension loss was a measly 28Hz, or about 2.8 lbs.
- Pretty sure this is the pre-stretched stuff now.
- Will advise CK to string this poly really low. 40 lbs could be a good start for a hybrid and high 30s for a fullbed. Reason being it was pre-stretched, and also to allow some ball pocketing, without which there would not be heavy spin.