North Highland Malts
North-Highland malts tend to be light bodied, delicate whiskies with complex aromas and a dryish finish sometimes spicy, sometimes with a trace of salt. Some are faintly peaty (Highland Park, Scapa, Clynelish, Balblair); in others the smoke is more like Lapsang Suchong (Pulteney, Teaninich, Dalmore). They cannot take too much sherry-wood maturation (although, the sherry-finishing technique developed at Glenmorangie suits them well).
East Highland Malts
The malts from distilleries north of Aberdeen - Macduff (the product is named Glen Deveron in its proprietary bottlings), Knockdhu, Ardmore, Glendronach and Glengarrioch - are medium-bodied, malty, slightly sweet, smooth, slightly smoky and with a surprisingly dry finish. South of Aberdeen - Royal Lochnagar, Fettercairn, Glencadam - they become richer, more toffee-like, with citrus notes, but still a whiff of smoke and still the dry finish.
West Highland Malts
West Highland malts are much less peated than their southen cousins in Islay, although they all have at least a whiff of smoke and a mildly phenolic flavour. If there is a uniting factor it is the sweet start and the dryish, peppery finish.
Central Highland Malts' Characteristics
The offerings from the Central Highlands are a mixed bag. Generally they are lighter-bodied and sweeter that their cousins to the east, but not as sweet as Speysides. Like Speysides, they are fragrant - blossom, violets, elderflowers, heather, mint, spice, pears: all these words appear in the tasting notes - but they tend to have a dry finish.