Softbox Color temp?
Actually softboxes can change color temperature quite a bit. The primary difference in WB between different boxes is due to age, not brand. It helps to buy all of your boxes together so that they age together.
But even with a brand new box, the light will be noticeably warmer than from a bare flash head. Usually an 1/8 CTO over the bare head will suffice (although far more often than not the difference doesn't bother me).
|Common Flashwing by digimania|
from canon dslr
|The Marilyn impersonator by Lee8282|
from Blowing in the Wind (Nature)