Assertion: tuba's valve | /r/CapableOf | enable the instrument
Facets:
value: to produce the low e
type: PURPOSE
value: with use of valves
type: MANNER
Source sentences:
text: The E♭ bass generally has a fourth valve that lowers the basic pitch by a fourth to BB♭, enabling the instrument (with use of valves) to produce the low E, below which the compass can be continued downward in fundamentals (lowest note producible by a length of tubing), E♭, D, and so on.