Make possible by sound, losing tempo (6)
I believe the answer is:
enable
'make possible' is the definition.
(I've seen this before)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for enable that I've seen before include "Make possible, give the means to do something" , "Capacitate" , "Allow" , "Empower" , "Permit or facilitate" .)