From Bare Knuckle:

The Blue Note is a smooth, warm P90 with a very open voice and touch sensitive dynamics, producing a fat but really articulate vintage soap bar tone.

The combination of slightly under-wound coils of 42AWG plain enamel wire and sand-cast Alnico II magnets give the Blue Note 90 a crisp, percussive tone with excellent response to pick attack. Compared to the Half Note 90, the bottom-end is fuller and high-end a lot sweeter which has the effect of softening the mid range. High notes sing with a true, vocal-like quality while the mids have enough weight to punch through without ever sounding honky or nasal. Clean tones are balanced with lovely note separation and chime to each string; driven tones are effortless and easily go from subtle break up to classic crunch.

Although voiced primarily for blues and cleaner playing styles, the Blue Note 90s are more than capable of contemporary tones too.