Yesterday I had a small accomplishment I was quite proud of. For months I've been making coffee at my new house in SF and it's had a bitter aftertaste I haven't been able to get rid of. I've changed the roast, grind, preparation, everything, and it was really bothering me.
I noticed that it was far less prominent when I made french press than when I made say pour-ever, and then yesterday a friend suggested I change the water.
Voila! New water completely fixed it and the result has been fantastic since. I've been making cups constantly in my excitement.
Dang you San Francisco water!