Head to head

Gosen Polylon 16 vs Kirschbaum Pro Line I 17 (1.25)

Pro Line I 17 (1.25) leads on 4 of 6 measurements. The widest gap is string friction, where Polylon 16 is 9 percentile points ahead. Every figure is a testing-machine result at a fixed reference tension.

Measured, side by side

Gosen

Polylon 16

Polyester · 16 ga

Kirschbaum

Pro Line I 17 (1.25)

Polyester · 17 ga

Stiffness lower = softer, kinder on the arm
20775th pct
20573rd pct
Tension loss lower = stays where you strung it
5190th pct
5190th pct
Energy return higher = livelier, more free power
826th pct
8310th pct
Spin potential higher = more spin off the string bed
4.132nd pct
4.132nd pct
Ball bite higher = grabs the ball harder
0.3574th pct
0.37510th pct
String friction lower = strings slide and snap back
0.08739th pct
0.09148th pct

Bars are percentile against all 791 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 Polylon 16 at 52 lb

String Pro Line I 17 (1.25) at 51.9 lb 23.5 kg

Coming from Pro Line I 17 (1.25) at 52 lb

String Polylon 16 at 52.1 lb 23.6 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.

Polylon 16 mains / Pro Line I 17 (1.25) crosses

Stiffness74th pct · 1 measured
Tension loss90th pct · 1 measured
Energy return7th pct · 1 measured
Spin potential32nd pct · 1 measured
Ball bite5th pct · 1 measured
String friction42nd pct · 1 measured

Pro Line I 17 (1.25) mains / Polylon 16 crosses

Stiffness73rd pct · 1 measured
Tension loss90th pct · 1 measured
Energy return7th pct · 1 measured
Spin potential32nd pct · 1 measured
Ball bite9th pct · 1 measured
String friction46th 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.

Polylon 16

~13 hours of play

Pro Line I 17 (1.25)

~13 hours of play

Both strings in full

Every published measurement
StringGaugePriceStiff lb/inLoss %Power %SpinBite COFFriction COF
Gosen Polylon 16 Polyester16find20751824.10.3570.087
Kirschbaum Pro Line I 17 (1.25) Polyester17find20551834.10.3750.091

Add a third string Polylon 16 in full Pro Line I 17 (1.25) in full