Yep, appears to have both RCA and optical inputs.Surely that speaker has an Aux socket so you could wire in any CD player
not too sure why he would want this when he can get better results by simply wiring the speaker, unless it's going to be miles from the CD player but that's unlikely / impracticalA bluetooth transmitter with RCA inputs will do the job. https://avantree.com/eu/tc417-bluetooth-transmitter-receiver