Head to head

IsoSpeed V18 19 (1.12) vs Luxilon ALU Power Feel 18/1.20

They split the measurements 3–3. The widest gap is ball bite, where V18 19 (1.12) is 50 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

Luxilon

ALU Power Feel 18/1.20

Polyester · 18 ga

Stiffness lower = softer, kinder on the arm
18046th pct
18754th pct
Tension loss lower = stays where you strung it
4068th pct
4372nd pct
Energy return higher = livelier, more free power
8733rd pct
8737th pct
Spin potential higher = more spin off the string bed
5.159th pct
5.467th pct
Ball bite higher = grabs the ball harder
0.48371st pct
0.39621st pct
String friction lower = strings slide and snap back
0.09455th pct
0.07412th 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 ALU Power Feel 18/1.20 at 50.1 lb 22.7 kg

Coming from ALU Power Feel 18/1.20 at 52 lb

String V18 19 (1.12) at 54.0 lb 24.5 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 / ALU Power Feel 18/1.20 crosses

Stiffness49th pct · 1 measured
Tension loss69th pct · 1 measured
Energy return34th pct · 1 measured
Spin potential61st pct · 1 measured
Ball bite66th pct · 1 measured
String friction45th pct · 1 measured

ALU Power Feel 18/1.20 mains / V18 19 (1.12) crosses

Stiffness51st pct · 1 measured
Tension loss71st pct · 1 measured
Energy return35th pct · 1 measured
Spin potential65th pct · 1 measured
Ball bite29th pct · 1 measured
String friction20th 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

ALU Power Feel 18/1.20

~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
Luxilon ALU Power Feel 18/1.20 Polyester18$21.5018743875.40.3960.074

Add a third string V18 19 (1.12) in full ALU Power Feel 18/1.20 in full