Is the diatonic harp used in a mariachi ensemble?

Yes, it is. The diatonic harp, also known as the "arpa," is a common instrument in mariachi music, contributing its unique and beautiful sound to the traditional Mexican genre. The arpa is usually played by a skilled musician known as the "arpista," who plucks the strings to produce melodic lines that complement and harmonize with the other instruments in the ensemble. The diatonic harp adds a touch of elegance and richness to mariachi music, making it an integral part of the lively and vibrant performances.