Here are a few examples of open note heads and their corresponding note values:
1. Whole Note: An open note head placed on a line or space of the staff represents a whole note, which is the longest note duration in standard notation. It lasts for four beats in a 4/4 time signature.
2. Half Note: An open note head with a stem represents a half note, which lasts for two beats in a 4/4 time signature.
3. Dotted Notes: An open note head with a dot after it indicates a dotted note. A dotted note is increased in its duration by half of its original value. For example, a dotted half note lasts for three beats in a 4/4 time signature (two beats for the half note plus one beat for the dot).
4. Note Groups: Open note heads are also used in groups to form chords or arpeggios. In most cases, open note heads signify the first note of a chord or arpeggio, and the other notes are indicated with stems and note heads or slashes.
It's important to note that the rhythmic interpretation of open note heads can vary depending on the musical genre and the time signature. For instance, in some types of music, such as jazz or contemporary music, an open note head might indicate a tenuto (held) note or an improvised passage, where the performer has freedom in how long to hold the note.
Overall, open note heads are a notation element used to represent notes of longer durations and play an important role in specifying note values and rhythms within a musical composition.