Excellent modeling and very nice painting.
An awesome start! Several good details. I really like the "plug" area for the amp cord.
Suggestion: I'd like to see some "aging" on the white plastic parts, too. That would be more consistent with the scratches on the wood. Not just generic scuffs, but think about where dirt will collect in crevices, and how raised areas get rubbed. Also consider where the hand rests and rubs while playing, and how the dirt and oils will affect the color and roughness in those areas.
Really nice work. Thank you for sharing.