The assertion is debatable. Detail is often achieivable with lower noise floor or higher S/N ratio in processors/preamps, players and amps. Hence, those newer DACs with very low noise floors as well as those new high resolution format like the DVD-A with 24 bit encryption (6db per bit = 144db of S/N) are supposed to yield better detail.
Detail can also come from excellent transparency where the signals have the least THDs and IMs to obfuscate the signals as recorded. However, I must say that if the player, amp or speaker has a slight emphasis anywhere from 6khz to 14Khz, a perception of greater detail can be had. But that would be a disservice to the accuracy and neutrality of the affecting gear.
So if the Yamaha has an emphasis in these spectral regions, there will be a relative perception of brightness and in-your-face forwardness that can impart better detail over one that has a flatter response. In fact, many members in our local forum have this impression of Yamaha. I haven't personally compared one with a Denon. But comparing it to an Onkyo, I would have to say that the Yamaha has a brighter edge. But different models may exhibit different perceptions of brightness form any brand. This is just my assessment. You may have to just audition them to hear for yourself.
