Airy: Spaciousness, often a pleasant mostly treble-based reverb sound. Extended frequency response that runs up through the top end of the bandwidth.
Brittle: Peaking in high-frequencies, weak fundamentals with slightly distorted or harsh highs.
Crisp: Good high-frequency response with good transient quality
Crispy: Constant, but perhaps random high frequency sounds not unlike frying foods.
Delicate: Extended high frequency range without being harsh. Emphasis on high frequencies extending to 20 KHz, but without the peaking.
Edgy: High frequency emphasis from about 3.5 to 6 KHz with harmonic content overly strong in comparison to fundamentals. Can deal with high frequency distortion and rasp.
Piercing: Hard on the ears, screechy and sharp. Narrow peaks occurring between 3 and 10 KHz.
Raspy: Harsh sounds in the 6 KHz range that sounds like a scratchy voice.
Sibilant: S and Sh sounds are overly emphasized.
Sizzly: Similar to crisp, like the sound of the decay on a riveted cymbal.
Steely or Shiny: Lots of top end from 3-6 KHz with peaky highs (as opposed to flat but boosted top end)
Sweet: Flat high-frequency response without distortion and extended the full bandwidth.