Thrushes have some of the loveliest songs among North American birds.
American Robin singing before dawn (July, ME)
The first two phrases are the typical "caroled" notes, and the next two are higher pitched "hisselly" phrases (see the sonagram). The typical American Robin sings 10-20 different carols and 75-100 different hissellys (Kroodsma). Hissellys are heard most reliably at dawn and dusk. During the day robins usually sing only caroled phrases.
This bird hidden in a conifer sang a song comprised only of hissellies (90 minutes after sunrise, Apr, PA). It was then chased off by a rival male.
Another example of a song comprised mostly of hissellies. In this case the bird was visible and sang with the bill in a slightly open but frozen position, and so it probably qualifies as a whisper song, a quiet song made without opening the beak fully. Quiet songs are often associated with aggression. (7.40am, Apr, PA).
Call notes are often interspersed between song phrases. In this example, the bird sang on the ground in darkness, then (at 60s) flew up into a tree, called for a time, and then resumed singing. There were very few hissellies in this dawn song (5.45am, Apr, PA).
Veery, at least two, possibly three birds countersinging, with calls in between song phrases (July, ME).
Hermit Thrush (July, ME)
Hermit Thrushes alternate lower with higher phrases.
The first three phrases:
Two Hermit Thrushes countersinging (July, ME).
Wood Thrush (June, NJ).
The regular song is three-parted, but sometimes only the last part is sung, especially later in the season per BNA (June, PA).
Wood Thrush singing a common song variant with calls and split phrases (with Carolina Chickadee, June, NJ)
Swainson's Thrush (June, AK)
Swainson's Thrush singing an abbreviated song (June, AK)
Swainson's Thrush adding calls to the song sequence (July, ME).
Gray-cheeked Thrush (June, AK). The song can be divided into four parts, the introductory note being the first part. The third part rises, and the fourth part is the descending series. In Bicknell's Thrush, the third and fourth parts are switched, so that its song rises at the end.
Eastern Bluebird, song 40 minutes before sunrise (June, PA). The phrases of the song at dawn often start with alarm notes.
The first four phrases:
The regular day song (Mar, PA).
Eastern Bluebird singing in fall (Oct, PA).