Head to head

Babolat SpiralTek 17 vs Tecnifibre HDX Tour 17 (1.24)

HDX Tour 17 (1.24) leads on 5 of 6 measurements. The widest gap is ball bite, where HDX Tour 17 (1.24) is 58 percentile points ahead. Every figure is a testing-machine result at a fixed reference tension.

Measured, side by side

Babolat

SpiralTek 17

Nylon · 17 ga

Tecnifibre

HDX Tour 17 (1.24)

Nylon/Polyurethane · 17 ga

Stiffness lower = softer, kinder on the arm
14912th pct
1447th pct
Tension loss lower = stays where you strung it
178th pct
110th pct
Energy return higher = livelier, more free power
9381st pct
9388th pct
Spin potential higher = more spin off the string bed
5.671st pct
5.774th pct
Ball bite higher = grabs the ball harder
0.41836th pct
0.57894th pct
Snapback lower = strings slide and snap back
0.07411th pct
0.10165th 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 SpiralTek 17 at 52 lb

String HDX Tour 17 (1.24) at 53.9 lb 24.4 kg

Coming from HDX Tour 17 (1.24) at 52 lb

String SpiralTek 17 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.

SpiralTek 17 mains / HDX Tour 17 (1.24) crosses

Stiffness10th pct · 1 measured
Tension loss4th pct · 1 measured
Energy return85th pct · 1 measured
Spin potential73rd pct · 1 measured
Ball bite51st pct · 1 measured
Snapback25th pct · 1 measured

HDX Tour 17 (1.24) mains / SpiralTek 17 crosses

Stiffness9th pct · 1 measured
Tension loss2nd pct · 1 measured
Energy return85th pct · 1 measured
Spin potential73rd pct · 1 measured
Ball bite91st pct · 1 measured
Snapback56th 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.

SpiralTek 17

~38 hours of play

HDX Tour 17 (1.24)

~40 hours of play

Both strings in full

Every published measurement
StringGaugeStiff lb/inLoss %Power %SpinBite COFSnap COF
Babolat SpiralTek 17 Nylon1714917935.60.4180.074
Tecnifibre HDX Tour 17 (1.24) Nylon/Polyurethane1714411935.70.5780.101

Add a third string SpiralTek 17 in full HDX Tour 17 (1.24) in full