I've implemented a 2.5-30MHz Synthesizer using an AD9850. I use it as a sine wave generator only, and of most importance is ABSOLUTE amplitude and phase stability! Now I was successful in reducing the amplitude noise by driving the DAC outputs slightly beyond it's compliance limits to "clip" the output waveform (1.6Vpp differential). Since I'm using a 5th-Order low pass at the output of the DDS, the clipped waveform isn't a problem, but how about the DAC? Is it going to work fine in a long-term point of view or do you recommend using a separate clipping amplifier to do the job?