Running CDP directly into MC275??

Does anyone do this?  I have an Esoteric K-07 and was considering the an MC275, but I see no reason for a preamp since I only listen to CDs.  Bad idea?
I'm doing just that. Oppo 103 directly into Vincent SP-331. Sounds wonderful. In order to use the volume control of the CDP when playing SACDs I needed to select PCM instead of DSD.

Its not a bad idea, a lot of people do that, but there are pitfalls.
Some CDPs use a digital volume control. Essentially, they subtract bits from the total so as to reduce volume. So as the volume is decreased, the signal quality suffers from reduced resolution.
Add to this the fact that the CDP puts out too much voltage (as required for some insane reason by the Redbook spec), such that it can clip any amplifier made and this means you have to run it **all the time** with the volume less than full!!
So one method used is a passive volume control interjected between the CDP and amp. The problem here is that the series resistance caused by the control can interact directly with the low frequencies and the extreme high frequencies of the CDP (the latter having a lot to do with the interconnect cables used) which can result in colorations, including loss of bass impact and overall dynamic quality.

However in practice many people are alright with this, likely because they've not heard what a good active preamp can do (as opposed to a poor one) in their system.

To get away from the problem of cable colorations, an active preamp is used, which restores the bass impact and reduces colorations, despite the fact that an active circuit is used. How successful this works varies quite a bit as not all active preamps are created equal and some don't work as well as none at all. Hence the active/passive debate raging on this and other audio websites.

So you do have to be careful (if you want optimal results) regardless.
Now if your CDP has an analog control (some of the Oppos do) and its good at controlling the cable, then this strategy might work quite well.

I advise doing a bit of audition if getting the most out of your system is the goal. If you just don't care then just hook up the CDP directly and call it good :)
@atmasphere Thank you for the detailed reply.  I verified that my CDP does have analog volume control, so I MAY be OK.  I guess that I will have to try.  Thank you again.
Everything sounds great, but I have been up to -2 dB already once.  Is this were a preamp would help, with gain?  I have it hooked up via XLR now, if I went with a single ended preamp, I would lose some dBs, but if the preamp had 12 dB of gain, that should suffice, correct?
It better. You probably don't need even that. But its not bad to run your control all the way up. If you can clip the amp, you don't need anymore gain.
OTOH if that's not happening an active will sort things out.
My vote is no. I have tried it with several preamplifiers, and without on my Mac 2105 which has gain controls, so that the source isn't involved, and in every case, the sound was better with the preamp. It was better proportioned, and more dimensional.
^^ I've always felt an active sounded better too, and to the above comment I will add: 'better bass impact and extension'.