Pubul57, direct coupled usually means no capacitor in the signal path. However, Atma-Sphere preamps have capacitors in the signal path, just not in the output coupling stage. Coupling capacitors on the output are placed there to block any DC from getting to your amp and possibly to your speakers if the amps are also direct coupled - this can damage your speaker. Capacitors impart their own colorations to the sound; for example, paper in oil caps are known to have a very relaxed smooth sound, but some find them muddy and slow sounding. They also can limit low bass response and roll off the top end. The larger the capacitor value, more sonic coloration will be imparted. The largest value cap is usually the output coupling cap in order to block DC and not to limit low bass. These are generalizations of course, but most would agree caps do add colorations to some degree. So getting rid of output caps will increase dynamics, extend the low and high frequencies, and in general have more neutral sound. That's how I see it. I'm not legally or technically responsible for the above statements.
