but if you are not happy with the JL2 than you may never be happy, it is an incredible amp even before the "upgrade".
I can see [hear] why many people would not like the sound of a CAT amp.....especially if the rest of the system is on the ultra-resolving side of the fence and lacking midrange fullness and bloom. However, if the final evaluation is being done with the stock tubes, and this is true for so much gear out there, you ain't heard nothing yet.
No matter what set of tubes are in the CAT, it has outstanding dynamic contrasts. But for $300-400 to replace the 6 small-signal tubes, much of what the reviewer talks about with the Atma amps vs the JL2 Sig II could be a moot issue and in fact might turn the tables. The cost of such a tube change is a lot less $$ than spending $15k more for an amp change. And if such a change occurred, I'd go back to the Atma amps and try some NOS 6SN7's to squeeze out the next level of performance from them.
Making any kind of conclusion on tube gear with stock (Sovtek, EH, JJ, etc.) tubes says nothing about that component's true potential. This was very evident with the Einstein preamp and more recently the Aria WV preamp. But amps are just as responsive to tube rolling.
John
