David Pelham says of the Colombian tiple: "The tiple is a Colombian adaptation of the Renaissance Spanish vihuela brought to the New World in the 16th century by the Spanish conquistadors. At the end of the 19th century, it evolved to its present shape. Its twelve strings are arranged in four groups of three: the first group consists of three steel strings tuned to E, the second, third and fourth groups have a copper string in the middle of two steel strings. The central ones are tuned one octave lower than the surrounding strings of the group. This arrangement produces the set of harmonics that gives the instrument its unique voice. Outside of Colombia the "copper" strings are more often standard brass or bronze wound steel guitar strings.