First "audiophile" system, now what? Suggestions for best "bang for the buck" upgrade?


After being beguiled with mp3s and the TV AVR, I finally realized I missed having a dedicated stereo system. With a budget of $2400, here is what I put together:
  ProJect Carbon 1 w/TizoAcrylic platter and Ortofon Red cartridge,
  Hagerman Bugle2 preamp,
  Vincent V-60 tube amp,
  Martin Logan 12 speakers.
 No special wires or cables. My room is 14x19 that is open to the kitchen. Compared to what I had been hearing, this system sounds fabulous. But now I want more fabulous. So I am writing to seek help on making short term/long term plans to upgrade. Short term means the biggest improvement in sound that costs $500 or less. The long term plan could cost maybe $2-3k or more. I have read that going from Ortofon Red to Blue might be a an inexpensive but very noticeable improvement? If speakers are my weak link, then maybe Martin Logan electrostatics would be good (when my ship comes in)?
I welcome any suggestions.
128x128etwilley
Nice to have you on board the good ship Audiophile! 

Your solution is contained in your post. You seem to dismiss cables as efficacious elements of a high end rig. I have had the pleasure of changing the opinions of industry members (read manufacturers - well known ones) and 4 or 5 engineers who mocked cables, but now pursue aftermarket cables for their purposes. 

I suggest you put your $500 to work on procuring a set/loom of cables for the rig. It will collectively be as important sonically as the addition of a new component. It is one of the easiest and most effective steps a person can make to obtain better sound. 

If you disagree, I'm not interested in debating the subject.  :) 
First, congrats on realizing AVR's and mp3's are great for sound effects and convenience, but for pure music reproduction, dedicated stereo systems are the best way to go.  So, nice system you have put together to start enjoy music the way it's meant to be heard.

WRT the next upgrade, the transducers (cartridge at the front end and speakers at the back end) in a system will always give the biggest impact on how a system sounds.   So you have probably answered your own question in your initial post - upgrading the cartridge from a 2M Red to a 2M Blue should provide the best bang for your buck that's within your current budget.  A nude elliptical is a big step up in performance from a bonded.  Next would be the speakers and that would strengthen the two so very
important transducers in the chain.

Good luck.

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Before I would spend any money, I would contact John Rutan at AudioConnnection in Verona, New Jersey.  He's extremely knowledgeable, and willing to help all us audiophiles that don't know how things interact, what the next step should be, etc.  Its worth a phone call...he loves to schmooze, and you will certainly benefit.