Related Clues:
- Critical measurements in "Apollo 13"
- Critical measurements in 'Apollo 13'
- Mic enhancers
- Excites, with "up"
- Short spins?
- Causes to roar
- Woodstock stage gear
- Stage flankers
- They pump up the volume
- Gives it some gas
- Rock music boosters
- Axe augmenters
- Audio elevators
- Concert blasters, briefly
- Tests an engine