Explain the difference between first, second, and third position harmonica playing, detailing their respective scales, and typical applications in blues.

Harmonica positions, referring to the key in which the harmonica is played relative to the key of the song, are crucial for blues players, as they provide different tonal characteristics and melodic possibilities. First, second, and third positions are the most commonly used, each offering distinct scales, note choices, and applications within the blues idiom. First position, also called "straight harp," involves playing the harmonica in the same key as the song. For example, a C harmonica is used to play a song in the key of C. In first position, the main scale utilized is the mixolydian mode, which is a major scale with a flat 7th. In the key of C, for example, the mixolydian mode would be C-D-E-F-G-A-Bb. The root of the chord is on a blow note and is easy to play, which makes it good for learning. The emphasis is on the major sound, making first position suitable for more melodic and less bluesy sounds, as the minor blues notes are not as readily available. The first position is also often used for playing melodies. Although it is less common in blues than second position, you'll find it used by some traditional players for a brighter, cleaner sound. You can use the mixolydian to play a solo, and play more of the major notes, and it has a more uplifting feel than a minor scale. It's not as useful for that classic, gritty blues sound because of the lack of strong minor notes. Second position, also referred to as "cross harp," is the most frequently used position for blues harmonica. In this position, the harmonica is played in the key a perfect fourth higher than the key of the song. So, a C harmonica would be used for a song in the key of G, and an A harmonica would be used for a song in the key of E. The scale most commonly used in second position is the blues scale, which includes the root, minor third, perfect fourth, flat fifth, perfect fifth, minor seventh, and octave. When playing in G blues scale in second position (using a C harmonica), we have G-Bb-C-C#-D-F-G. One of the major advantages of second position is the ease with which you can bend notes, and also that all the draw notes have good blues notes. The blues notes are mostly on the draw notes, which are bent to play minor thirds and the flat fifth. The flat fifth is the main note that contributes to the blues tonality. The second position creates a strong bluesy sound, ideal for playing licks, solos and rhythmic patterns in the blues, because of the easy access to those crucial blues notes by drawing and bending. It is very easy to find those bluesy bends, and that makes it suitable for improvisation. Third position involves playing a harmonica two whole steps up from the song’s key. Thus a C harmonica would be used for a song in the key of D. In the third position, the scale often u....