Speaker Cable Connector Accepting 2 Pairs of Cable

I have speakers that accept only 1 pair of banana plugs. The female speaker cable outlets are inset and flush with the rear of the speaker. My current speaker cables are terminated with banana plugs and I want to add a second set of speaker cables terminated with banana plugs or spades depending on the adapter that I can find. The second cable set will connect to a supertweeter. If you are aware of such an adapter I would be grateful if you can let me know. I have searched on the Web and could not find one. Thanks.