Mcintosh question

1. Not necessarily.  Depends on the source/DAC/CD.

2. Yes, the MCD550 has a built-in volume control that you can use.

3. The function of a preamp is to provide additional voltage gain that may not be available from the source (to better drive an amplifier) and to provide a volume control. Additionally, the preamp will add its own sonic signature, which may or may not be what you want. Generally, a lower priced solid-state DAC will usually need a preamp to make the sound less digital. In your case, you’re going to mate a McIntosh CD to a McIntosh tube amp. You may not need a preamp to help with sonic signature.

4. See answer to #3 above. A nice Class A or tube preamp can help the sound be more natural for a very solid-state source and solid-state amp. However, since your dealing with a Mac CD player and a tube Mac amp, I don’t think you’ll need additional preamp.

5. I would start a thread in the preamp forum tittled "Recommend preamp for MCD275". Lots and lots of opinions. I am not a McIntosh expert here. However, C22 is a very old vintage Mac product that probably needs work - replace electrolytic caps, probably replace all volume/level potentiometers. The C2500 is much newer, but I’m sure more expensive.

6. Most likely the DAC in a preamp will not be as good as your MCD550. Shared power supply and less amount of circuits for analog stages, DAC voltage, etc.

7. Your MCD550 can be used as a DAC because has multiple digital inputs (coaxial, toslink, usb). You can connect any digital player, media streamer, computer to it. MCD550 will support PCM audio up to 24/192.

8. This is entirely personal preference.

I don’t know that I would say the signal is degraded by going through a tube amp or preamp. Every piece of equipment affects the sound in different ways. It all depends on what kind of sound you are looking for. Of course, mating a low cost Adcom amp with something like a McIntosh CD player definitely has the possibility of "degrading" the sound. However, it also depends on the person’s budget.

It sounds like you are wanting to try the MC275 tube amp. Tubes have their own sonic signature and can be different than solid state. That being said, the McIntosh sonic "character" is more warm and laid back (can also be described as "rich" sometimes). It is not my preference for sound character as I want more neutral and high-resolution sound, but many love the McIntosh sound.

You should go out and see if you can find someplace that has the MC275 to listen to. It might give you a better idea of what to expect. Then, if you like what you hear, buy an MC275 and connect it directly to your MCD550 (using the MCD550 volume control). It might be that you are fine with this combination. If there’s something missing, then post a thread in the preamp section describing your system and then describe the sound that you are after.