This is a 1982 Sigma D-18 made by the C.F. Martin company. Martin started the Sigma line to compete with the influx of guitars from Yamaha, Ovation and Takamine to cater to the middle end guitar buyers. This guitar has resonance and sustain that you would find in high in guitars and would easily compete against $1200.00 to $1800.00 guitars. It is made from select woods and construction was monitored every step of the way by Martin luthiers. It has a solid spruce top and mahogany sides and back. This guitar bellows when attacked and rings when picked. One of the finest acoustics I have played at any price.