Talking point

 Another interesting quote from a period source courtesy of Chris Page "The performance of songs in late medieval France: A new source". This comes from the 15th century romance, Cleriadus and Meliadice and describes how after dinner, in the great hall:

the minstrels began to play loud wind instruments [commencerent a corner] . A great lord of the court took the fair Meliadice. Cleriadus took one of the ladies and all the men and women began to dance. The entertainment lasted a long time And when they had danced their fill the minstrels ceased and they began to sing. There might you have heard men and women singing well! Now Meliadice was next to Cleriadus and another knight in the retinue of the Count. She said to Cleriadus: 'Pray sing a song from your country; you have heard enough songs from ours'
. . . And then Cleriadus began a song so well that all those who were there listened to him gladly. They all said that they had never heard anyone sing so well. Even the king himself
stopped talking to hear Cleriadus.

Page's main point in quoting this passage is to note that minstrels stop playing when the singing starts, as evidence that singing was (generally) unaccompanied. Although it is apparent that the loud winds being used by the minstrels on this occasion would not be suitable to accompany song in any case, there is also no mention here (or elsewhere) in the romance of other, quieter, instruments being used when songs were being performed (although, interestingly, there is several times mention of dancing to singing; and also a passage in which Cleriadus composes music for a rondeau sent to him by Meliadice, and immediately "put it on the harp" and played it). Rather, there are several explicit mentions of polyphonic music being sung by two or  three people, e.g. Cleriadus calling on a young page to sing with him, and a squire to hold the tenor.

But what I particularly like about the passage is that "Even the king himself stopped talking..." to hear the performance. Suggesting that it was certainly not unusual for music to be occurring against a background of conversation.