Conrad Johnson SS amps


I am currently looking for a new power amplifier to drive my Martin Logan CLSIIs (4ohm load). I am deciding between CJ's MF2250 and MF2500. I was wondering what the difference was between the the stock model and the "A" model. ie: MF2250 vs. MF2250A. I would also like to know if they can they be bridged? Would I get better results using two MF2250 amps or a single MF2500 amp?
msilin
Unsound:

I think I may be able to help you with the MF 2300. I have been using CJ's prior line of amplifiers for a long time, and I think they are an excellent combination of power and warmth.

I first purchased an MF 2100 for my nominal 6 ohm speakers. I was very impressed with the sound of the amplifier, for it easily powered my moderately inefficient speakers quite well throughout the entire spectrum. The bass was tight and controlled, the midrange was warm yet detailed, and the highs were very detailed but not etched. I credit my CJ preamp for some of this as well, but I tried this amplifier with four other distinctly different preamps, and I always found the amplifier to have similar characteristics. There is no question that the CJ preamp and MF 2100 yielded the best results.

I then bought an MF 2300A. When I connected it to my system (cold) after an extensive listening session with the MF 2100, I was stunned by the improvement. The soundstage was deeper and wider, and the bass response was even deeper and more articulated. Whether at low volume or high, the MF 2300A produced incredible musicality. When it had warmed up for an hour, the sound of the amplifier was even warmer.

I later upgraded my speakers to a pair of ribbon hybrids that fluctuate between 3 and 6 ohms. The MF 2300A was still able to control the deepest bass easily, and the highs were even more impressive and natural (the ribbons really make a difference). I can't say enough about the MF 2300A's performance.

I have no experience with the current CJ solid state amplifiers except for a brief period at a dealer. From everything I have read about the new amps, it sounds like they do not have CJ's typical sonic characteristics (i.e. warmth and tube-like performance).

I hope that this is helpful to you. If you can purchase a used MF 2300 or 2300A in good condition, I think that you will be very happy.

Msilin, thanks for your indulgence.
Overhand and Vortex, thanks for your input.
Overhang: Thanks for that info. Does this mean that both CJ 2300 and 2300A are both MOSFET-based amps?

Has anyone else noticed the "hole" in the MF2500A's lower mid/ upper bass that was described by Overhang?