Brilliant, richly resonant and responsive tone. A sound that packs a punch and stands up in the mix while lasting up to 3X longer than a standard string. Crafted of 92% Copper and 8% Zinc, Blue Steel acoustic strings are cryogenically frozen with a blast of liquid nitrogen which gives them these special qualities. By freezing the strings down to -320ºF, tighten the molecules, minimising microscopic gaps. This process removes transient frequencies that produce harsh highs and muddy lows, creating a more consistent string, with true tone and longer life.