A post on the SF board asks the following question that I'm taking to the General Board:
Could you enlighten us enthusiastic pho newbies as to the diffs between northern and southern style pho? Is it the broth? The type of noodles? The meat garnishes offered? The veg plate garnishes offered? Chowish minds want to know.
I don't purport to be any expert on pho. My parents are from the north so I grew up eating nothern style pho, or pho bac. Lately I've been in a pho phase and have tried 4 different pho houses over the past couple weeks, so I've been thinking a lot about how pho differs from place to place.
To me, I think pho bac is more about how well a simple beef broth can taste supremely delicious, and southern style pho or pho nam is more about what you add to the pho to make it a complex whirl of tastes and fragrances.
So a good pho bac is so good you don't want to add any of the garnishes to it except a couple drops of lime and a tiny splash of nuoc mam (fish sauce), at the table of course. But a good pho nam is the interplay of the broth with the perfume of the herbs and the texture of the sprouts and onions.
I've got other thoughts but I wanted to know what others have to say about this. I also found a very interesting and well-written ode to pho posted in 2004 (link below).