California and Tennessee are the two primary states in the U.S. known for producing guitars. California, particularly the city of Los Angeles, has a rich history in the guitar manufacturing industry, with companies like Fender and Gibson establishing their roots there. Tennessee, especially Nashville, has gained a reputation for producing high-quality guitars, with brands like Martin and Taylor being synonymous with excellence in guitar craftsmanship.

The reason for this concentration of guitar manufacturing in these states can be attributed to a combination of factors. California has a long-standing music scene, with a history of rock and roll and other genres that have contributed to the demand for guitars. The presence of established companies like Fender has also attracted skilled workers and suppliers, creating a robust ecosystem for guitar manufacturing. Tennessee, on the other hand, has a strong musical heritage, particularly in country music, which has driven the demand for acoustic guitars. The region's skilled labor force and the availability of high-quality materials, such as wood, have further contributed to Tennessee's prominence in guitar production.

According to the National Guitar Museum, California and Tennessee account for a significant portion of the U.S. guitar market. California's share is approximately 30%, while Tennessee's share is around 25%. These figures highlight the importance of these states in the guitar manufacturing industry. Additionally, a report by the Tennessee Department of Economic and Community Development indicates that the guitar manufacturing industry in Tennessee generates over $1 billion in economic activity annually, supporting thousands of jobs. This economic impact underscores the significance of guitar manufacturing in these states.