Original sentence: Drugstore records mostly comprised popular music played or sung by unknown orchestras or singers, or conversely, once famous singers or orchestras playing music or songs that were relatively unknown.In most cases the record album would have only one cover version of a famous song or tune but exciting album cover artwork and the low price would attract customers
Edited sentence: Drugstore records mostly comprised popular music played or sung by unknown orchestras or singers, or conversely, once famous singers or orchestras playing music or songs that were relatively unknown (popular singers' early and obscure recordings were often showcased as well).In most cases the record album would have only one cover version of a famous song or tune, but exciting album cover artwork and the low price would attract customers