I’ve heard the Oscar Duo as well, but I’ve never heard a rich or full enough sound out of them. Light but detailed would describe what I’ve heard.
That would apply to the Marten Duke 2 as well. The overall presentation is a little lean and light in comparison to speakers with a fuller midrange and bass. The touch with the Marten is more refined and delicate especially in the treble. The sound is smooth but detailed at the same time. In contrast, other speakers may sound more strident by showing a more forward presentation with a brighter piercing treble.