I owned a CJ MF2300a that was recently recapped...while it didn't have the same punch and dynamics of the 4B3, it did have more soundstage and upper range imaging. The 4B3 in my system was way too laid back, dark and frankly not all that impressive. The recent DNA-1 is a fantastic amplifier and gets into the music more while still keeping the character I had with the CJ amp. Have a new pre-amp inbound now too as the gain on my LS17 is not a good match for the DNA-1