Glass of bourbon next to decanter of bourbon
Why The Size Of The Rim Of Your Bourbon Glasses Actually Matters
An important design element in bourbon drinkware is the rim (or mouth) of the glass, whose size and shape affect the smell of the particular bourbon you're sipping.
A narrower bourbon glass rim condenses the scents together, whereas a wider rim will disperse, creating a milder nose. Glasses with narrow rims are best for drinking bourbon neat.
Newer glass designs, such as the NEAT whiskey glass, are flared in an attempt to concentrate the desired scents while minimizing the harshness of the ethanol.
A glass with a wider rim is best for cocktails and mixed drinks, as the smell of the drink doesn't need to be concentrated the same way and better contains the drink's volume.
If you're serving a large crowd, you can also hide a lower-quality whiskey's poor characteristics with a wide-rim glass since it will mute the scent.