80/20 Bronze wound strings are often called old-school, vintage and/or bright bronze and were the most popular (only) alloy used to make acoustic strings until the introduction of phosphor in the early Seventies. 80/20 bronze wire is made from 80 percent copper and 20 percent zinc. 80/20 bronze provides a balanced highs and low with a slight increased in mid-range that seems the make the notes cut-through a little more.9-9-12-12-20w-9-26w-12-36-20p-46-26