Rondo Violoncello

Professional players choose Rondo strings for their exceptionally deep and focused tonal intensity. A fast bow response supports their direct character at any dynamic level, while the strong focus offers a great projection of this rich and complex sound.


RO400 SET, Medium Tension, 4/4 Scale
Tension 61.20kg/134.80lb


RO4344 Twin Set, Medium Tension, 4/4 Scale

Out of stock

Tension 28.10kg/61.90lb


RO4142 Twin Set, Medium Tension, 4/4 Scale

Out of stock

Tension 33.10kg/72.90lb


RO41 Single A-String, Medium Tension, 4/4 Scale
Carbon Steel, Multialloy, Tension 18.80kg/41.45lb


RO42 Single D-String, Medium Tension, 4/4 Scale
Carbon Steel, Multialloy, Tension 14.30kg/31.53lb


RO43 Single G-String, Medium Tension, 4/4 Scale
Spiralcore, Tungsten/Chrome, Tension 14.30kg/31.53lb


RO44 Single C-String, Medium Tension, 4/4 Scale
Spiralcore, Tungsten/Chrome, Tension 13.80kg/30.42lb


Set details

The RONDO set RO400 is appreciated by professional musicians due to its intense tonal depth and accurate bow response at a vast range of dynamic levels. The particular essence of the set RO400 is its innovative synthesis of a barrel-chested, velvet-like sound with the greatest possible “density” and a crystal-clear focus. By merging these qualities to a deep singing sound with a mature vocal character, it creates the widest range of sonic variations, a powerful presence at all dynamic levels and a new playing experience. The set impresses with its maximum resistance to bow pressure and immediate bow response at various bowing speeds, bow pressures and contact points. These strings tonally enrich both old and modern instruments with their intense depth, brilliant contour and sweetness – sound qualities mostly associated with “old Italian” instruments.

Single string details

The set RO400 includes the strings RO41, RO42, RO43, RO44.

The A-string RO41 was developed as an innovative synthesis of the highest tonal noblesse, maximum “inner” tonal density and brilliant openness. Regardless of dynamic levels and playing techniques, its barrel-chested voice and velvet-like sound texture give the RO41 a vocal character that is further enriched with a well-defined focus. A special feature of the RO41 is its almost endless resistance to bow pressure and articulated hard bowing techniques. Its gentle left-hand feeling contributes to an easy modulation of sound colors, even in the quietest passages.
All these attributes are present from the lowest to the highest registers with outstanding projection, making the A-string RO41 a preferred choice for soloists.

The D-string RO42 is an extremely powerful and focused D-string that offers a distinctive deep and round tone quality. Despite its substantial warmth, this D-string’s fine brilliance imparts a special grace and transparency in its overtone spectrum. RO42 directly reacts to a progressive increase of bow pressure with a more intense and compact sound whilst retaining its open character, even when played with very high bow pressure and slow bowing speed. Its timbre can be easily modulated to reach a radiant and heroic presence – a quality that defeats the most common flaws of a weak D-string on the cello.

The G-string RO43 possesses an outstanding ability to modulate sound when changing the contact point. Velvety and dark tones can be achieved by approaching the fingerboard, vice versa, a small move towards the bridge will brighten up the sound. Like the other strings in the set RO400, the RO43 guarantees an accurate response due to its high resistance to bow pressure. In combination with the C-string RO44, the G-string RO43 blends the punchy and clear tone quality found in Thomastik-Infeld’s tungsten-wound Spirocore string S32 with an additional depth of tone and incredibly fine, rich overtone structure. The G-string RO43 represents the ideal image of a soloistic Cello G-string with its almost unlimited dynamic range and high sound intensity.

The C-string RO44 is the string with the richest and deepest sound of the setRO400. At every dynamic level the string reacts convincingly to subtle changes in articulation and playing technique. If desired, a velvety warm tone can be produced even with a clear start. Conversely, a direct bright tone can be produced even with a smooth start. This C-string offers an exceptional resistance to bow pressure. In combination with the G-string RO43, the C-string RO44 blends the punchy, crisp and clear tone qualities of Thomastik-Infeld’s tungsten-wound Spirocore string S33 with an additional profound tonal depth and great refinement. These attributes make the RO44 a first choice for accomplished soloists.

Mix and match

The set RO400 is perfectly balanced. Mixing it with different single strings can change its original character, which can be used to optimize its performance depending on your and your instrument’s needs.

With other Thomastik-Infeld products:

When combined with three lower Rondo strings, the A-string VES41 adopts some of their qualities and sounds darker than in the full Versum Solo set. Compared to the A-string RO41, VES41 works on a lower tension level with a different string design, offering a broader character on most instruments. Especially when the cello’s A-string leans towards a bright and narrow tendency, using the combination with VES41 can be a great help.

To add more focus to the high register, we recommend using a combination of Versum Solo’s D-string VES42 and A-string VES41 with Rondo’s G-string RO43 and C-string RO44. Both the A+D as well as the G+C strings are available as twin sets (VES4142, RO4344). In this combination, more focus is added to the generally broader character of the Versum Solo’s A+D strings while making Rondo’s RO43 and RO44 slightly smoother and darker. Matching these four strings offers a resonant and warm sound, which allows especially the top strings to breathe and shine.

The tungsten-wound Spirocore C-string S33 is a globally respected reference string choice on the cello. Using this string in combination with the other three Rondo strings will give the set a more resonating and sparkling tone. The very powerful and brilliant C-string S33 itself becomes a bit darker while keeping its exceptionally crisp character. The upper strings, especially the A-string RO41, become inspired by S33 so as to increase their overtone spectrum and their sensitivity to bowing speed.

Technical details

Rondo Violoncello 4/4
NR Tension Core material Outer material TAILPIECE END KG LB PEG END
RO41 a la I Medium Carbon Steel Multialloy
Brass Ball end
18.80 41.45
RO42 d re II Medium Carbon Steel Multialloy
Copper Ball end
14.30 31.53
RO43 G Sol III Medium Spiralcore Tungsten/Chrome
Nickel Crimp ball end
14.30 31.53
RO44 C Do IV Medium Spiralcore Tungsten/Chrome
Brass Crimp ball end
13.80 30.42
SET NR. Included in set Tension KG LB
RO400 RO41, RO42, RO43, RO44 Medium 61.20 134.80
RO4142 RO41, RO42 Medium 33.10 72.90
RO4344 RO43, RO44 Medium 28.10 61.90


Share on email
Share on whatsapp
Share on facebook
Share on pinterest
Share on twitter

You are now a gold member!

Here you can check your latest orders and reorder them.

Welcome to the Thomastik-Infeld string universe. We are happy that you let us be part of your musical journey.

Your benefits at a glance:

  • Austrian quality: You will get all the advice and information directly from the string manucture in Vienna
  • Open 24/7: Direct access to all offers on all your devices
  • Very personal: Your data and settings will remain protected and unchanged
  • Always up-to-date:Receive notifications about new products and offers
  • Save time: Save favorite products and payment methods for later

Hallo, the cart is waiting to be picked up ;)

Sign in to your account