String comparison
RPM Team vs Sonic Pro
Babolat RPM Team against Head Sonic Pro: ratings, specs and which one fits your junior.
The short answer
Both are polyester strings. RPM Team leads on power, spin, control, durability and tension hold. They score the same for arm friendliness (3/5). Sonic Pro costs less per set.
Ratings
Power
Spin
Control
Comfort
Durability
Tension hold
Ratings are on a 1–10 scale. The higher score is in bold when they differ.
Pick RPM Team if…
- You want more power (7 vs 6 out of 10)
- You want more spin (8 vs 6 out of 10)
- You want more control (9 vs 8 out of 10)
- You want more durability (8 vs 6 out of 10)
- You want more tension hold (8 vs 5 out of 10)
- Best for: players who like Blast but want more comfort
- Best for: juniors with fast swings seeking control
- Best for: all-court players wanting spin with comfort
Pick Sonic Pro if…
- You want to spend less (from $8 vs $17 a set)
- Best for: budget-conscious players wanting poly
- Best for: club players in regular competition
- Best for: those wanting all-round playability
Specs side by side
| Spec | RPM Team | Sonic Pro |
|---|---|---|
| Type | Polyester | Polyester |
| Construction | Eight-sided co-polymer with silicone coating and micro air bubbles | Unique co-polymer polyester with soft molecular construction |
| Gauges | 16, 17 | 16, 17 |
| Stiffness | Medium high | Medium |
| Set price | $17–19 | $8–12 |
| Reel price | $120–140 | $90–120 |
| Arm friendliness | 3/5 · Moderate | 3/5 · Moderate |
| Cost to maintain | 4/5 | 5/5 |
| Recommended from | Age 13 | Age 13 |
| Levels | Intermediate, Advanced, Elite | Intermediate, Advanced |
| Play styles | Baseliner, All court, Big hitter | All court, Baseliner |
| Junior tension | 48-52 lbs for juniors. Holds tension better than Blast so can string at normal range. | 50-54 lbs for juniors. Best in mid-50s. |
RPM Team in short
The string of choice for Carlos Alcaraz when he won his first Grand Slams. Launched in 2012 as a more comfortable version of RPM Blast, RPM Team combines an eight-sided shape for bite with a cross-linked silicone surface to boost snapback. What sets it apart is its low-density design using micro air bubbles to cushion ball impact. Despite being designed for comfort, it tested as one of the firmest Babolat strings in the lab - proving the air bubble technology works. Better tension maintenance than Blast makes it more cost-effective for frequent players.
Sonic Pro in short
Head Sonic Pro combines unique co-polymer polyester with a soft molecular construction for good touch and comfortable feel. "A great all-round string that delivers on its promise of control and comfort." Received remarkably low stiffness scores compared to most polys tested. Power level slightly higher than average for a co-poly. After an hour of hitting it softens up and feels livelier. Best in the mid-50s tension range - at higher tensions it plays too dead, lower tensions lose control. Budget-friendly at $8-12 per set.
RPM Team vs Sonic Pro: quick answers
Which has more spin, RPM Team or Sonic Pro?
Babolat RPM Team, with a spin rating of 8/10 against 6/10.
Which is more arm-friendly for a junior?
They score the same, 3/5. RPM Team is recommended from age 13 and Sonic Pro from age 13.
Which lasts longer?
Babolat RPM Team rates 8/10 for durability against 6/10.
Which is cheaper?
RPM Team costs about $17–19 a set and Sonic Pro about $8–12, at typical retail.
The short answer and the "pick if" lists are generated from our ratings and junior data only. Data verified 2025-01 (RPM Team) and 2025-01 (Sonic Pro).