Very nice! The use of media makes it even more impressive, especially how you've captured the reflections in the smooth surfaces of the violin. I am taking extra note on the side close to the hand. Very nice.
The overall artstyle is also nice, presenting a nice mix of realism and comic-book rendering. Whilst the shading of the violin and hands are more real, the hair, face, neck and some other shadows are more comic-bookesk. However, they all come together into a truely nice piece!
Some constructive critism though that also motivates my 4.5/5. First, the violin looks a bit warped. The piece closest to the player is a bit too high I think and second I'd liked you to have been a bit braver with the contrast, i.e. a bit bolder dark colors. Perhaps you can do a post-color correction in the digital media and add some more contrast?
My critism is however nitpicking as the overall piece, especially being a traditional drawing, is amazing and I could see it being a hanged painting or wallpaper in someones home. Really well done :)