The C-1 is a stereo pre-amp.
What did you replace with the Sony system? Just the Carvers or the speakers too?
The speakers will have the greatest influence on the sound. A receiver replacing the Carvers should sound similar unless you are making use of the tone controls on the C-1. If that's the case and you just want to add sources but keep the sound the same, you may be best off to add separates. You won't find a CD player and tuner in one unit. Even if you replace the Carvers with a receiver you would still need to add a CD player.
It's easier to find a DVD or blue-ray player these days and they will play audio CDs just fine. You can simply ignore the video connection if your system is for music only. Sony makes some nice blue-ray players, but if you don't mind used consider local thrift shops or Goodwill stores. They often have old audio gear and CD players are cheap. You may have to try a couple before you find a good working one and it may take some searching to find one that comes with a remote. If you prefer new we can make some recommendations.
Separate FM tuners are getting harder to find as well. You can also try used or look on Ebay or Craigslist, but if you want new a simple solution is
this unit on Amazon and it's only $164. The C-1 has a tuner input and any CD or blue-ray player can connect to any of the auxiliary inputs.
