One string tackles five challenges! Cellist and product manager Attila Pasztor presents the new Thomastik-Infeld A-string RONDO® Experience.

RONDO® for Cello

  • Clear and velvety
  • Smooth transition
  • The present D-string
  • Play automatic!
  • Fast response

Thomastik-Infeld RONDO® RO400 have been tested by over 500 professional cellists worldwide on instruments of the famous old and new masters. The product offers lots of radiance, color, volume and projection, especially for new builds. The strings are very present and masculine with an intense depth of sound, meaning they are more likely to meet the demands of professionals and advanced players. For beginners, enthusiasts and those looking for a more subdued sound character, we recommend Thomastik-Infeld Versum® strings.

The Thomastik-Infeld RONDO® product line is defined by a very clear, powerful and direct sound with a velvety tone color. Cello strings are often associated with the throaty singing of a tenor. However, RONDO® strings sound closer to the chesty voice of a baritone, giving the cello a full, rich and deeper sound. These sound characteristics are also what set the strings apart from other, well-known strings and alternatives within the current Thomastik-Infeld range. 

The RO400 set is very homogeneous. The strings are matched in such a way that the tonal and haptic transition between the strings is hardly noticeable. 

Cellists frequently complain that the sound and volume of D-strings deteriorates after a short time. This was taken into account in the development of this set, and the RONDO® D-string was deliberately manufactured to emanate a present sound. This makes it a stable bridge between the G- and A-string! The entire set is very powerful and the strings’ sound fills the room even when little bowing pressure is applied.

The strings respond smoothly and without resistance to every change in playing. All Thomastik-Infeld RONDO® strings offer a playing feel comparable to a driving experience with automatic transmission: they create a comfortable and balancing feel across all four strings in all registers and positions. 

RONDO® strings have a fast and precise response that is not aggressive. 

You’re faced with many challenges on the podium: temperature, humidity, acoustics, your own (nervous) tension. This volatile interplay can make it difficult to completely control movement and sound. Thomastik-Infeld automatic strings provide the perfect support here – they are less sensitive to changes in the contact point between string and bow. This allows these strings to compensate for any possible losses in quality (e.g.: response, sound density, tone beauty) and react predictably and reliably. They provide a comfortable and balancing feeling, comparable to the automatic transmission of a car. 

  • If the instrument itself already has a high sound density or needs relief, we recommend RO41XP.
  • If the instrument needs more focus and contour, you need RO41.

The Thomastik-Infeld RONDO® A-string RO41 is characterized by a continual sound density. The string delivers a particularly refined sound in pianissimo and a solid sound in forte – in clear contrast to "just loud". RO41 does not scream. Regardless of the instrument's character, the sound is always full and beautiful while still offering a good capacity for modulation.


Technical Details:

The Thomastik-Infeld RONDO Experience® RO41XP is a very vibrant string and offers an exceptional amount of sparkle and overtone richness compared to the regular RO41. It reacts even faster to bowing impulses from the right hand and at the same time produces a clear, distinct sound with minimum effort from the left hand.

The string has 700g less string tension, but it is exceptionally powerful and creates a very compact sound despite a broad range of tonal colors, unlike other softer strings. However, unlike the standard RO41, the sound density of the RO41XP is lower. Even though it feels softer (than the RO41), it offers a nice resistance. Compared to the RO41, the RO41XP is more sensitive to bow pressure and bowing speed, offering a higher capacity for modulation. Due to its forgiving character, the RO41XP maintains contact close to the bridge very reliably even when the bow pressure is insufficient.

Due to its even faster response (see RO41), the Thomastik-Infeld RONDO Experience® RO41XP allows impulsive interpretations and new playing experiences as a result.


Technical Details:

The Thomastik-Infeld RONDO® D-string RO42 is a present-sounding string with an open, clear and radiant tone color. Despite this clarity, it has a profound keynote. The string’s register is baritone, yet still brighter than other D-strings in this spectrum. A special feature of the RO42: Usually the G-string on the cello is the supporting string for the entire set. But the RO42 assumes this function as a D-string. Unlike conventional D-strings, it does not take any tonal energy from its neighboring strings. It actually supports them. The A-string, in particular, becomes more open and full-bodied. In addition, RO42 reacts smoothly and with reliable resistance to changes in playing.

Technical Details:

The Thomastik-Infeld RONDO® G-string RO43 is a sporty, offensive string that produces high volumes and sound dimensions even with minimal bow pressure. Nevertheless, it has a noble, supple timbre and currently offers the greatest possible focus of all our G-strings. The G- and C-strings in the RO400 set are also perfectly matched.

Technical Details:

The Thomastik-Infeld RONDO® C-string RO44 has an intense, deep timbre with a velvety and refined character. It sounds very rich, yet loses neither contour nor clarity. Compared to the G-string, its sound is more modulable and somewhat less direct. RO44 is a real sound booster. Due to the absolutely reliable response to all changes in bow pressure, speed and position, you feel like you can really dive into the string.

Technical Details:

Sound Chart Cello

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