Ken Smith Acoustic Guitar Crystal Bronze Round Wound, .013 - .056, AR-CBMstar rating 5Chuck PaulOctober 18, 2010My guitar tech gave me a pair of these strings when I went to him for some adjustments. I was blown away by the tone,then by the incredible longevity. I play 5-6 nights per week and I have these strings on now for just about 3 weeks. Normally I use Martin Bronze, which I have no complaint with, but these smith strings are incredible...rich tone, holds the tuning...and LONGEVITY....fantastic!!