Music: A necessity or a hinderance?

So lets talk about music. Do you have a "soundtrack" to your writing or do you prefer the quiet?

I personally need the music. I have a writing playlist if you will. Some of the bands on my playlist are Disturbed, Godsmack, Linkin Park, Metallica, Muse and Shinedown. Depending on which part of my book I am working on, I listen to certain bands to set the tone of my writing. The 'heavier' and 'darker' parts of my book are written to Disturbed and Godsmack. Both David Draiman and Sully Erna have dark, raw voices which work well with the subject. I tend to listen to Bon Jovi, Lenny Kravitz and Muse for the lighter and  romantic moments in the book.

I really think that the music enhances my writing and helps to set the mood of the scenes I'm writing at the time. But hey, that's just me...