Gamma IO 18 (1.18) vs Tourna Black Zone 17

Measured, side by side

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.

• More spin and shape

  IO 18 (1.18)132nd

  Black Zone 17145th

• Easier on my arm

  IO 18 (1.18)365th

  Black Zone 17353rd

• More control, less launch

  IO 18 (1.18)363rd

  Black Zone 17408th

• More power and depth

  IO 18 (1.18)368th

  Black Zone 17344th

• Plays the same for longer

  IO 18 (1.18)395th

  Black Zone 17405th

• Lasts longer before it breaks

  IO 18 (1.18)2nd

  Black Zone 1750th

• Best feel and touch

  IO 18 (1.18)348th

  Black Zone 17338th

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.

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.

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.

Both strings in full

Add a third string IO 18 (1.18) in full Black Zone 17 in full