No, there does not seem to be a "whoompf" noise. When the
heat goes on, (what I suppose is) the ignition assembly does run
for about 10-15 seconds before it ignites the flame, but when
it finally does, it seems to ignite smoothly, at the moment the
little ignition light goes on.

The basement also smells of the oil, and specifically only when the
furnace has been running - not so much otherwise.

Regards
Andre