Head to head

Babolat RPM Blast Rough 16 vs Tecnifibre Black Code 4S 17 (1.25)

Black Code 4S 17 (1.25) leads on 5 of 6 measurements. The widest gap is energy return, where RPM Blast Rough 16 is 7 percentile points ahead. Every figure is a testing-machine result at a fixed reference tension.

Measured, side by side

Babolat

RPM Blast Rough 16

Polyester · 16 ga

Tecnifibre

Black Code 4S 17 (1.25)

Polyester · 17 ga

Stiffness lower = softer, kinder on the arm
21079th pct
20978th pct
Tension loss lower = stays where you strung it
3047th pct
2844th pct
Energy return higher = livelier, more free power
9061st pct
8955th pct
Spin potential higher = more spin off the string bed
8.297th pct
9.899th pct
Ball bite higher = grabs the ball harder
0.57793rd pct
0.65899th pct
Snapback lower = strings slide and snap back
0.0705th pct
0.0672nd 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 RPM Blast Rough 16 at 52 lb

String Black Code 4S 17 (1.25) at 52.1 lb 23.6 kg

Coming from Black Code 4S 17 (1.25) at 52 lb

String RPM Blast Rough 16 at 51.9 lb 23.5 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.

RPM Blast Rough 16 mains / Black Code 4S 17 (1.25) crosses

Stiffness79th pct · 1 measured
Tension loss46th pct · 1 measured
Energy return59th pct · 1 measured
Spin potential98th pct · 1 measured
Ball bite95th pct · 1 measured
Snapback4th pct · 1 measured

Black Code 4S 17 (1.25) mains / RPM Blast Rough 16 crosses

Stiffness79th pct · 1 measured
Tension loss45th pct · 1 measured
Energy return58th pct · 1 measured
Spin potential99th pct · 1 measured
Ball bite99th pct · 1 measured
Snapback2nd 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.

RPM Blast Rough 16

~26 hours of play

Black Code 4S 17 (1.25)

~27 hours of play

Both strings in full

Every published measurement
StringGaugeStiff lb/inLoss %Power %SpinBite COFSnap COF
Babolat RPM Blast Rough 16 Polyester1621030908.20.5770.070
Tecnifibre Black Code 4S 17 (1.25) Polyester1720928899.80.6580.067

Add a third string RPM Blast Rough 16 in full Black Code 4S 17 (1.25) in full