[jiggawatts]

Just to be pedantic: You can never smell the alcohol (ethanol) in any alcoholic drink. It's a tasteless and odourless chemical. What you taste or smell are the congeners, which are other organic molecules that are the byproducts of fermentation. In the case of whisky, you also have the additional flavour and odour chemicals leached from wood barrels.

You're basically smelling "charred wood extract" when smelling Whiskey.

[abduhl]

Ethanol has a distinct smell. It is neither tasteless nor odorless.

[Karunamon]

If you pop open a bottle of Everclear or IPA, what is it you're smelling?

[supernova87a]

That's not totally accurate. Alcohols do have smells, but true, for drinks it's probably not the dominant thing you remember.

It's quite obvious how different ethanol versus isopropyl alcohol versus methanol smell (former chemist) when pure.

[jiggawatts]

You're almost certainly smelling the denaturing agent in the alcohol, the vast majority of commercial sources add something to it, even for "technical" grades.