Final answer:
Changes at the end of the basso continuo period included the shift from modal to tonal characteristics and increased importance of root motions of fifths. There was also a greater demand for music with the invention of the Gutenberg press and significant cultural shifts in music composition and dissemination, leading up to the birth of opera.
Step-by-step explanation:
At the end of the basso continuo era, significant changes took place in musical theory and practice. The modal characteristics of Renaissance music, which were rooted in modal systems rather than tonality, began to transform as composers increased their use of root motions of fifths. This was a crucial development that led to the tonal system, which is the foundation of much Western music that followed.
The demand for music increased remarkably with the widespread accessibility of printed materials due to the Gutenberg press. Music not only became a source of entertainment but also a pastime for the educated middle class. The fluid style of polyphony was unified in this period, with the contributions of notable composers like Palestrina and Byrd.
Concurrently, the political and cultural hubs of music shifted into cities such as Venice and Rome, especially by the late sixteenth century. These changes set the stage for the emergence of new musical forms, including opera, which sought to recapture the musical spirit of ancient Greece.