Apparation question

[alora]

*de-lurking*

I hope this is not too off topic, but I have a question and I wonder 
if there is something to it, or nothing to it.  In the past books, 
when Harry hears some one Apparate or Disapparate, it is sometimes 
described as a "pop."  Now, in OoP, Harry hears the "crack"  sound, 
as when Mundungus leaves Harry alone to go after the stolen 
cauldrons.  Before, I thought only Dobby went "crack"  when he 
disappeared.  I'm going to go back and read the chapter in OoP where 
the twins are apparating - I can't remember if the sound is 
described or not.  I was just wondering if the sound is connected to 
the ability ie a "pop"  if they have been apparating for a long time 
and  "crack" when someone is still new at it.  Or as in Mundungus' 
case, possibly drunk?  I don't know!  Does anyone else have any 
thoughts on this?

Alora