Excitation patterns smooth the spectrum, blurring harmonic and formant detail the acoustic signal carries

Evidence

The excitation pattern, on the other hand, provides a smoothed representation of the power spectrum. The representation of the individual harmonics and the formants, although easily visible in certain frequency regions, are not nearly as pronounced as in the spectrum. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 508

Categorization

• XREF: connects to: Excitation spread across frequency bands is modelled as convolution with a level-dependent spreading function. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1588