Sure, kathylkirk, I'll give it a go.
go to Bluetooth menu at the top left of your screen, looks like a Capital B, click on the cog to get to preferences, forget or remove the speaker if it's there. don't worry, it's not gone for good, just for now, It'll be back soon. make sure that under the Bluetooth menu that Bluetooth is on and your mac is discoverable for bluetooth. Then reset smc/pmu and zap pram on your MacBook Pro, how to do that can be found on Apple's support page for notebooks, or google/yahoo it, after having done that,
now we take care of the speaker side of things....look for a small hole on the back of the speaker, this is the reset button and is usually reachable with a straightened paperclip. I don't know exactly what model of HarmonKardon speaker you have, so all I can do is give you general suggestions. Usually shutting down the speaker, waiting 30 seconds, then holding down the power and bluetooth button together may do something good. after your MacBook Pro has restarted, and you have done the reset smc, etc etc....then your speaker should appear in the bluetooth menu as a device, click on "Pair" then OK and it should be good to go, I hope.....
however, I don't know the exact name or model so I can't do a lot.
john b