Head to head

IsoSpeed V18 19 (1.12) vs Prince Tour XP 15L

They split the measurements 3–3. The widest gap is string friction, where Tour XP 15L is 24 percentile points ahead. Every figure is a testing-machine result at a fixed reference tension.

Measured, side by side

IsoSpeed

V18 19 (1.12)

Polyester · 19 ga

Prince

Tour XP 15L

Polyester · 15L ga

Stiffness lower = softer, kinder on the arm
18046th pct
18551st pct
Tension loss lower = stays where you strung it
4068th pct
4474th pct
Energy return higher = livelier, more free power
8733rd pct
8739th pct
Spin potential higher = more spin off the string bed
5.159th pct
5.262nd pct
Ball bite higher = grabs the ball harder
0.48371st pct
0.43547th pct
String friction lower = strings slide and snap back
0.09455th pct
0.08331st 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 V18 19 (1.12) at 52 lb

String Tour XP 15L at 50.7 lb 23.0 kg

Coming from Tour XP 15L at 52 lb

String V18 19 (1.12) at 53.3 lb 24.2 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.

V18 19 (1.12) mains / Tour XP 15L crosses

Stiffness48th pct · 1 measured
Tension loss70th pct · 1 measured
Energy return35th pct · 1 measured
Spin potential61st pct · 1 measured
Ball bite68th pct · 1 measured
String friction48th pct · 1 measured

Tour XP 15L mains / V18 19 (1.12) crosses

Stiffness49th pct · 1 measured
Tension loss72nd pct · 1 measured
Energy return36th pct · 1 measured
Spin potential61st pct · 1 measured
Ball bite51st pct · 1 measured
String friction35th 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.

V18 19 (1.12)

~20 hours of play

Tour XP 15L

~18 hours of play

Both strings in full

Every published measurement
StringGaugePriceStiff lb/inLoss %Power %SpinBite COFFriction COF
IsoSpeed V18 19 (1.12) Polyester19find18040875.10.4830.094
Prince Tour XP 15L Polyester15Lfind18544875.20.4350.083

Add a third string V18 19 (1.12) in full Tour XP 15L in full