Thomastik DOMINANT PRO DP21 – Viola A String

Thomastik-Infeld DOMINANT PRO DP21 is a professional A string for 4/4 viola, featuring a carbon-steel core with chrome-steel winding. It belongs to the DOMINANT PRO series, developed for fast bow response, a wide dynamic range and balanced tone across all four strings.

Sound and playing characteristics

One challenge when selecting a viola A string is avoiding excessive brilliance or harshness compared with the D, G and C strings. Thomastik-Infeld designed DP21 to blend naturally with the DOMINANT PRO D string, rather than standing out from the tonal picture.

According to the manufacturer, DP21 offers easy playability, very little nasal coloration and extended tonal lifespan. It complements the series' characteristic dark and warm sound while maintaining clear articulation and strong projection.

Its responsive behaviour supports fine control of bow speed and pressure, allowing expressive dynamics in chamber, orchestral and solo performance.

Steel core and removable ball end

The carbon-steel core delivers direct bow response and reliable playing stability. The chrome-steel winding provides the string's playing surface and good resistance to wear.

A removable ball end allows installation with compatible ball-end fittings or, once the ball is removed, suitable loop-end fittings. Check the fine-tuner design before installation.

Technical specifications

Selection and maintenance

DP21 is a direct replacement for the A string in the DOMINANT PRO DP200 set and may also be considered for custom string combinations. The specified 37.5 cm is the vibrating string length, not the instrument's body length.

Remove rosin dust with a soft, dry cloth after playing. If using a loop-end fitting, remove the ball carefully without damaging the string loop.

Please note: this product contains one individual viola A string. The complete A, D, G, C set is sold under article DP200.