| Assuming your P-Bass has the standard type bridge then you can adjust the height of the strings by moving the bridge saddles up and down. These are adjusted by two screws, one at each end of each saddle - turn them clockwise to raise and anti-clockwise to lower the strings. You'll need either a small screwdriver or an allen key to do this. Remember to retune after doing this.
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Peter.
You hum it, I'll play it!!.
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