E-string with gold plated steel core. In the year 1998 the Obligato strings from the Pirastro company set the basis for the developing of a totally new string generation. They possess a warm, rich, sonorous tone quality and remain precise and focused at the same time. The impressive amount of volume and a very dynamic response make them suitable for all ranges. They get immediately playable and offer the highest degree of modulation. Advantageous for these new synthetic strings compared to gut strings is the longer durability and the resistance against temperature and humidity changes. They get quickly tuned.