Generally negative
A prospective buyer cites outside test reports claiming the tweeter on this model can sometimes override the mids depending on the type of music played. This was raised as a concern while comparing the 250 to the 225 the commenter already owns.
Generally negative
The same cited tests state that vocal reproduction is not the model's strongest suit, and that its mids lack the richness found in the higher-tier 230 and 240 models. This is reported secondhand by someone still deciding between models.
Generally negative
One commenter argues that Denon or Marantz electronics don't let the Diamond speakers fully shine, recommending an Emotiva amp and preamp combination instead. This suggests the speakers' performance can vary noticeably with the paired gear.