The earliest known document mentioning "a pipe called Recordour" dates from 1388.[18]Historically, recorders were used to play vocal music and parts written for other instruments, or for a general instrument. As a result, it was frequently the performers' responsibility to read parts not specifically intended for the instrument and to choose appropriate instruments. When such consorts consisted only of recorders, the pitch relationships between the parts were typically preserved, but when recorders were combined with other instruments, octave discrepancies were often ignored.[19]