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Gamma

IO Soft 17 (1.23)

Polyester Gauge 17 1.34 mm In production

Lab measurements for Gamma IO Soft 17 (1.23), ranked against all 789 strings in the database. Every figure below is a testing-machine result at a fixed reference tension, not a playtest opinion.

Measured values

Stiffness

193lb/in

lower = softer, kinder on the arm

Tension loss

34%

lower = stays where you strung it

Energy return

87%

higher = livelier, more free power

Spin potential

5.9

higher = more spin off the string bed

Ball bite

0.440COF

higher = grabs the ball harder

Snapback

0.075COF

lower = strings slide and snap back

How it ranks against all 789 strings

Stiffness 193 lb/in · 60th pct

Stiffer than 60% of strings tested.

Tension loss 34 % · 56th pct

Sheds more tension than 56% of strings tested.

Energy return 87 % · 39th pct

Livelier than 39% of strings tested.

Spin potential 5.9 · 78th pct

More spin potential than 78% of strings tested.

Ball bite 0.440 COF · 50th pct

Grips the ball harder than 50% of strings tested.

Snapback 0.075 COF · 13th pct

More string-on-string friction than 13% of strings tested.

Strings that play like this

Closest matches across stiffness, tension loss, energy return and spin potential.

Klip K-Boom 18 (1.20) 96% match Yonex Poly Tour Fire 16L (1.25) 96% match Tourna Black Zone 17 95% match Gamma IO 18 (1.18) 94% match Prince Tour XP 17 (1.25) 94% match Topspin Cyber Delta 17 (1.26) 94% match

More from Gamma

What these numbers mean

Stiffness · lb/in

How much the string bed resists deflection. Higher plays firmer and more controlled; lower plays softer and easier on the arm.

Tension loss · %

Share of the reference tension the string sheds under a fixed test protocol. Lower means the bed stays where you strung it for longer.

Energy return · %

Share of impact energy handed back to the ball. Higher plays livelier and more powerful.

Spin potential

Ball friction divided by string-on-string friction. Higher means better bite with a cleaner snapback, so more spin.

Ball bite · COF

String-on-ball friction. Higher grabs the ball harder through the brush.

Snapback · COF

String-on-string friction. Lower lets the mains slide and snap back into place after impact.

Compare IO Soft 17 (1.23) against 789 strings Find the right string for me