Well no, that's not the whole story. With the preamp on the Flex 6400 (-136 dB) is within 2 dB of the Elecraft K3 (-138 dB) on CW MDS/Noise Floor, (first column). Adjust the controls to fit the operating goal. Note: Of course, on HF bands, the atmospheric Band noise is typically the limiting detection factor for most stations (not to mention man made ambient noise). Excess sensitivity becomes useless and nothing more than a bragging point.