Decent BKK bars/pubs away from the obvious tourist traps.

[jayfx11]

Although I usually only spend a few days in BKK during my Thai trips, I really love the city but I often find myself a bit unsure of where to go and drink in the evenings. 

I cannot stand Koh San Road. I loathe the place (but I am nearly 40 now). Nana area is OK but crammed with tourists and overpriced lady bars. Soi Cowboy is just Agogos etc., and I'm looking for something different. 

Is there nay decent pubs or trendy bars away from these obvious tourist drinking spots? They don't need to be exclusively for Thais but somewhere that offers something different to the typical Soi 4, loud, pricey lady bar. Where do expats drink? I heard there's a few bars in Silom, is this correct? Where else is there?

Any recommendations would be much appreciated.