"Smell" is generally a neutral meaning, but used alone it can imply the smell is bad: "there's a smell in here". (I think the quote is, "the best smell is no smell at all", but that's Montaigne quoting a Roman writer.) To make the meaning definitely positive, you need a positive adjective like 'pleasant', 'lovely', or 'inoffensive'.
Some positive synonyms for smell are: aroma, fragrance, scent, perfume.
Some negative synonyms: stench, stink, reek.
Are you thinking of this for a business name? There is a "Hell Smell Studio" (recording studio) in Rome...