234974
For amplification , a single-coil pickup ( an uncovered P-90 pickup ) was installed on the top of the body at the edge of the fingerboard ( similar to " floating " pickups on some arch-top acoustic guitars ) , with a volume and a tone knob .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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