I have tried many preamps including Audio Research Ref 6se and Pass Labs XP 22. My MSB Analog DAC sounds better direct to my Pass Labs XA 100.8. Speakers are Wilson Sasha. Preamp adds coloration every time. DAC direct is more natural , has more detail and is definitely coherent across the frequency range
DAC DIRECT IN TO AMPLIFIER OR TO PREAMPLIFIER
For the longest time, I believed that the best preamplifier is no preamplifier. Eliminating a component from the audio chain would yield less distortion & greater purity.
Recently, I have had reason to re-think my logic on the matter - and I am (I think) changing my mind. Better said, assuming that the preamplifier in the component you are using (in my case, a DAC) can produce 95% or greater quality sound compared to the preamplifier component, then no preamplifier is the best option. The 5% represents the (estimated) loss of fidelity in adding another set of interconnects.
That said, most DACs do not have an outstanding preamplifier built in. I think most have average passive attenuators, and the better DACs have active preamplifiers that are very good - but not as good as a quality preamplifier.
What are your thoughts?