Are you sure they are not banana plugs, as shown here, rather than RCAs?
If that's the case, and your amp and speakers do not accept banana plugs, Google "banana to spade adapter" (with the quotes) and you'll probably find something suitable.
BTW, although it undoubtedly has no relevance in this case, I'll mention that 40 or 50 years ago or thereabouts there were some passive speakers manufactured that were connected to via RCAs. (Active speakers, containing their own amplifier, are of course often connected to via ordinary RCA interconnect cables).
Regards,
-- Al
If that's the case, and your amp and speakers do not accept banana plugs, Google "banana to spade adapter" (with the quotes) and you'll probably find something suitable.
BTW, although it undoubtedly has no relevance in this case, I'll mention that 40 or 50 years ago or thereabouts there were some passive speakers manufactured that were connected to via RCAs. (Active speakers, containing their own amplifier, are of course often connected to via ordinary RCA interconnect cables).
Regards,
-- Al