Cmach, your right, the Bat is most definately an upgrade from the SA-400 but more expensive. If I'm correct the Bat is a zero negative feedback design & uses only one gain stage, a superb amp! I know both the SA-250 & SA-400 are not a zero negative feedback design but a minimal negative feedback design (a good thing as well). Don't know how many gain stages the Sonographes employ. I would love to give the Bat a try one day but for now I will enjoy the SA-400. But I thank you for the heads up on the SA-400.
Conrad Johnson's Sonographe SA-250 or the SA-400?
Both of these amps unlike the MF series are Bipolar design rather than Mosfet. Although the Sonographe products are considered entry level for Conrad Johnson, there is nothing entry level about the sound quality or build quality! In fact I prefer the Sonographe sound to the MF series, maybe because I prefer the Bipolar sound now. Anyway I have owned more amps than allowable by law so when I first aquired an SA-250 I was immediately struck by the level of sound quality that it possesed. In fact this was exactly what I was looking for. This was an amp I could live with for a long time. From what I've gathered, the SA-250 was rated a Stereophile class B component, does anyone pay any attention to these ratings? Eventually I wanted more power & purchased the SA-400. Called CJ and they told me the sound of the SA-400 was identical to the SA-250 but with more power. I can now confirm this to be true. Conrad Johnson products are an excellent investment & the Sonograhe line is no different. Don't hesitate to give these amps a try, as they are major bargains on the used market.