Which preamp is better C50 or C2500 for MC402?

I have a Macintosh MC402 and a preamp C48, I would like to upgrade to either a preamp C50 or C2500. Do any of you guys have an idea of which preamp is better? I would appreciate your suggestions. Thanks
I don't think you will hear a difference between the C48 and C50. Thec2500 is whole different ballo wax. I sat on the ss/tube preamp fence for a couple of months. Went with a c2500 and am quite happy. Tube pre/ss amp pre magic
I have a 402 and have it coupled with a Audio Research LS26. I had a MX135 prior to the ARC, I did look at the C2300 when I bought the ARC. My point is not to steer you away from McIntosh as I really do appreciate the sound and build quality of their products. But my point is that getting a tube sound influence vs. another solid state, I believe brings the 402 to a new level of performance. Maybe that helps you, or not, but I am suggesting a stronger look at the C2500. YMMV of course.
The C50 and C2500 are roughly equivalent in price and features. As noted by the others, it depends much more on whether you want to go with the tube sound.

I had a C2300 for 6 months and loved it. But. It took about 3 hours or so to warm up and I couldn't leave it on 24/7. It also didn't reproduce some electronic instruments quite as crisply as I prefer.

So, I turned it in on a C50. Does the C50 sound as good on acoustic music from vinyl? No. Does it outperform with Al DiMeola, also from vinyl? Yes. Is the on-board DAC useful? Yes. Do I use it much? No. Does it warm up fast enough to allow me to actually listen to music rather than wait? Absolutely!

Both are superb units built to serve the same market differently. Give some thought to how you listen and what you listen to. Let that be your guide.

Good luck & happy listening!
I know this is an old discussion but I’m actually facing the same dilema as vinny8888 at this moment. Want to buy a good preamplifier and stay with McIntosh and my 402 but do not know if I want to go the tube (c2300) route or (c50), - not able to demo them actually -. I have had both tube and ss gear before so do not have a preference and I get effischer’s point, much depends on the music you play; I play mostly classic rock 60%; some jazz 25% and other stuff 15%, recently much internet radio (via cambridge streaming) and vinyl and cd’s (via oppo 95). So theo, and others my question is: which one is best taking into account this music I prefer? Agon members input is much appreciated. By the way: Speakers are B&W 804D2.
Or go with the Aesthetix Calypso and go to a whole new level.
I have Mac 501's with the C2200 and have heard this combo ( Aesthetix Calypso )and wow do they make a great PRE..
Thanks russe41, was also thinking of the Audible Illusions 3A, some say it is also top notch if I decide to go out of the McIntosh circle.
I have heard the Audible Illusions 3A extensively at a friend's who actually recently switched to a Calypso as an upgrade - his words, and I completely agree that it is indeed an upgrade. He had originally bought the AI for its excellent phone stage but his record collection is now all boxed up and temporarily stored in my basement. The Calypso is not quite broken in yet but it does have more detail and much better bass. He also used to complain about the AI's customer service and had it sent back twice for repairs, both times under warranty but took months to get it back.
I've had a C2500 for about 5 weeks now and love it.  I can''t comment MC402 but 2500 is a wonderful addition to my system.  The 2500 replaced my long time Musical Fidelity A308 full function pre-amp.  I purchased it on this site, new in the box with a 3 year McIntosh Warranty.  Please note, some older C2500's may need a "Firmware" update to correct a minor internal DAC/USB issues. The NOS one's you're seeing on this site have the latest "Firmware".

Good Luck!