The final fusion of Flamenco and the Flamenco guitar is in the 20th century, from it comes the structure of the different flamenco palos: Soleás, Alegrías, Seguriyas…
Flamenco becomes a spectacle.
Another difference, hardly perceptible to the eye, but decisive to the sound is the placement of the harmonic bars designed to perform flamenco techniques such as rasgueo, the movement that makes the cover vibrate and return to the repose position in very short time intervals.
And the fact beacuse flamenco guitar is different from classical guitar is due to the use of specific techniques: the picado, the flamenco tremolo or the arpeguios, for example. The sound of the flamenco guitar has less sonority than the classical guitar, at the same time it has a higher level of percussion.
These small differences between the classical and the flamenco guitar, draw the line that divides one sound from another. They are so subtle that usually the places where we can buy or repair a guitar work the two styles, classical and flamenco.