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Celebrating 20 Years

Superior Performance Guitar Strings

Did you know the inspiration for SP Core wire was “tire wire”?
If it’s tough enough for tires, it’s tough enough for rock and roll!

First developed in 1997, all SP (Superior Performance) products are made with high tensile strength bronzed steel core wire designed to stand up to rigorous practice and performance schedules and stay in tune like no other string on the market. The process of brass flashing the wire protects the steel from corrosion and keeps the strings sounding vibrant and true for the life of the string.


SP Acoustic Strings started the trend toward high tensile strength strings over 20 years ago and they remain the most tried and true high performance acoustic string on the market. SP strings are known for their consistent true tone and endurance. Players worldwide rely on them to stay in tune through busy practice, performance and recording schedules.

SP Lifespan Strings are the same great SP Acoustic strings you know and love, but Martin has added their proprietary treatment to all six strings for longer life. The treatment protects the strings from environmental elements that damage guitar strings over time. SP Lifespan strings are perfect for players that don’t like to change strings often but still want that true Martin tone and quality.

SP Flexible Core strings are truly unique in the string world and the absolute best strings for finger style players, like Tommy Emmanuel, or anyone looking for added comfort, flexibility and control. Because of the high tensile strength of the SP Core Wire, Martin is able to provide a thinner core wire while maintaining standard tensions, so you get added flexibility without compromising volume and tone.


Martin offers three unique wrap wires in the SP product line to provide even more options for all genres of music and styles of play.

92/8 Phosphor Bronze (on hex core wire):
Phosphor Bronze provides more volume and complexity in the upper harmonics for consistent true tone that is pleasantly vibrant and sustaining over the life of the string. This is Martin’s most popular wrap wire in the SP product line.

80/20 Bronze (on hex core wire):
80/20 Bronze tends to be brighter straight out of the package, but warms up quickly as the strings are played. 80/20 bronze strings are great for bluegrass players or anyone looking for a more mellow tone.

Silk & Phosphor (on round core wire):
Contains an added silk thread between the round core wire and phosphor bronze wrap wire for added comfort and subtle, warm tones. Perfect for singer songwriters. Available in SP Flexible Core only

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