I didn't write my first complete song until I was about 18, but the influences I had started much earlier. I have a dad who liked to jam to the oldies station (50's and 60's rock and doo-wop). I have already written about the oldies songs that make me smile on another site, and I am confident to say that the singable melodies and hooks I heard from the oldies have shaped my thirst for a good melody.
My Family's Influence
My brother liked to listen to The Beach Boys and Paul Simon and my Mom liked to play guitar and sing folk stuff. Mom is pretty creative, and my brother, Darin, has a natural musical ear talent where he can pick out and play anything on the keyboard that he hears in a song. I have to count them as influences because they have each written songs too, although I have become more obsessed about it. My older sister, Denise, although she didn't write songs, won a poetry contest and modeled for me that poetry can be a cool art. somehow I think I ended up a blend of everyone's influence, and I am grateful for my family influencing my songwriting.
I probably have the entire family to thank for getting me through the 1980's without exposing me to horrible music, and allowing me to subconsciously soak up some really great stuff.
When You Lose Your Virgin Ear
The end of what I would call my early songwriting influences was when I started taking piano lessons in second grade. Once formal music lessons start, you start learning a little music theory, and you start to listen to music with a critical ear. You know if someone is singing off key, out of rhythm, or other problems. Now, I have such a critical ear that sometimes I can't just enjoy a song for what it is, and sometimes I wish I could go back to before I learned what I know now.
Piano was my first instrument, and I still feel affection for keys even though I am prone to pick up the guitar more often now. I would consider the instrument that a person plays as an influence on his or her songwriting, because you get used to hearing certain tone, timbre, and dynamics.
What This Means for My Songwriting
The main thing that all this means is that I tend to like folk poetry lyrics, oldies-like melodies, Beach Boys song arrangements, and I value a variety of instruments in my songs. Maybe these are natural tendencies that I picked up as a child while my brain was growing and going through the pruning process. My own family helped my brain decide what musical skills I would likely need as an adult.