Head to head

Diadem Solstice Pro 15L (1.35) vs Solinco Outlast 18 (1.15)

Outlast 18 (1.15) leads on 3 of 6 measurements. The widest gap is energy return, where Outlast 18 (1.15) is 10 percentile points ahead. Every figure is a testing-machine result at a fixed reference tension.

Measured, side by side

Diadem

Solstice Pro 15L (1.35)

Polyester · 15L ga

Solinco

Outlast 18 (1.15)

Polyester · 18 ga

Stiffness lower = softer, kinder on the arm
19360th pct
18654th pct
Tension loss lower = stays where you strung it
2842nd pct
2740th pct
Energy return higher = livelier, more free power
8955th pct
9164th pct
Spin potential higher = more spin off the string bed
7.191st pct
6.687th pct
Ball bite higher = grabs the ball harder
0.54489th pct
0.50981st pct
String friction lower = strings slide and snap back
0.07717th pct
0.07717th 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 Solstice Pro 15L (1.35) at 52 lb

String Outlast 18 (1.15) at 53.8 lb 24.4 kg

Coming from Outlast 18 (1.15) at 52 lb

String Solstice Pro 15L (1.35) at 50.3 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.

Solstice Pro 15L (1.35) mains / Outlast 18 (1.15) crosses

Stiffness57th pct · 1 measured
Tension loss42nd pct · 1 measured
Energy return59th pct · 1 measured
Spin potential90th pct · 1 measured
Ball bite88th pct · 1 measured
String friction17th pct · 1 measured

Outlast 18 (1.15) mains / Solstice Pro 15L (1.35) crosses

Stiffness56th pct · 1 measured
Tension loss41st pct · 1 measured
Energy return61st pct · 1 measured
Spin potential88th pct · 1 measured
Ball bite83rd pct · 1 measured
String friction17th 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.

Solstice Pro 15L (1.35)

~27 hours of play

Outlast 18 (1.15)

~28 hours of play

Both strings in full

Every published measurement
StringGaugePriceStiff lb/inLoss %Power %SpinBite COFFriction COF
Diadem Solstice Pro 15L (1.35) Polyester15Lfind19328897.10.5440.077
Solinco Outlast 18 (1.15) Polyester18find18627916.60.5090.077

Add a third string Solstice Pro 15L (1.35) in full Outlast 18 (1.15) in full