Pick-up:
It's picking up the sound of an instrument and converting it into electricity or something, but it's picking up the sound and amplifying it. For example: electric guitar, acoustic guitar, through the pickup connected to the speaker, to achieve the effect of amplifying the sound.
Notes for the school:
It's the tuning of the instrument. Is this piano you are not tuned to the right tone ah, wrong to use it to help you tune with.
