StringSpec
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Browse all 788

Head to head

Kirschbaum Black Shark 17 (1.25) vs Luxilon ALU Power Rough 16L (1.25)

They split the measurements 3–3. The widest gap is ball bite, where ALU Power Rough 16L (1.25) is 38 percentile points ahead. Every figure is a testing-machine result at a fixed reference tension.

Measured, side by side

Kirschbaum

Black Shark 17 (1.25)

Polyester · 17 ga

Luxilon

ALU Power Rough 16L (1.25)

Polyester · 16L ga

Stiffness lower = softer, kinder on the arm
21785th pct
20978th pct
Tension loss lower = stays where you strung it
3865th pct
4066th pct
Energy return higher = livelier, more free power
8848th pct
8741st pct
Spin potential higher = more spin off the string bed
5.876th pct
6.586th pct
Ball bite higher = grabs the ball harder
0.42138th pct
0.49876th pct
String friction lower = strings slide and snap back
0.0727th pct
0.07717th pct

Bars are percentile against all 788 strings, and the marked side is the one that measures better, which is not always the one you want. A firmer bed is worse for your elbow and better for your control, and no measurement knows which of those you came for.

Which one wins, by problem

Each string's standing on the site's rankings, out of every measured string in the database. This is where a comparison stops being arithmetic and starts being a decision.

Swapping between them: what tension?

Bed stiffness is published at one reference tension, so the only honest conversion is to scale it. These are starting points from 52 lb, not prescriptions. The calculator takes your own tension.

Coming from Black Shark 17 (1.25) at 52 lb

String ALU Power Rough 16L (1.25) at 53.8 lb 24.4 kg

Coming from ALU Power Rough 16L (1.25) at 52 lb

String Black Shark 17 (1.25) at 50.2 lb 22.8 kg

Hybrid: what if you used both?

Estimated, not measured. No hybrid combination has been tested as a bed. These figures are the two strings' own lab measurements weighted by how much of the bed each one actually is. Treat them as a guide to which way a pairing moves, never as lab data.

Black Shark 17 (1.25) mains / ALU Power Rough 16L (1.25) crosses

Stiffness82nd pct · 1 measured
Tension loss65th pct · 1 measured
Energy return45th pct · 1 measured
Spin potential79th pct · 1 measured
Ball bite47th pct · 1 measured
String friction10th pct · 1 measured

ALU Power Rough 16L (1.25) mains / Black Shark 17 (1.25) crosses

Stiffness81st pct · 1 measured
Tension loss66th pct · 1 measured
Energy return43rd pct · 1 measured
Spin potential84th pct · 1 measured
Ball bite72nd pct · 1 measured
String friction14th pct · 1 measured

Open this in the hybrid builder

Which goes dead first?

Estimated from tension loss, which is the only thing the database measures about ageing. This is when the bed stops playing the way you strung it, not when the string breaks.

Black Shark 17 (1.25)

~20 hours of play

ALU Power Rough 16L (1.25)

~20 hours of play

Both strings in full

Every published measurement
StringGaugePriceStiff lb/inLoss %Power %SpinBite COFFriction COF
Kirschbaum Black Shark 17 (1.25) Polyester17find21738885.80.4210.072
Luxilon ALU Power Rough 16L (1.25) Polyester16Lfind20940876.50.4980.077

Add a third string Black Shark 17 (1.25) in full ALU Power Rough 16L (1.25) in full