Mature, yes, in the sense that you can engineer tube amps that sound a lot like solid state, and solid state amps that sound a lot like tubes. W.r.t. DACs, unless you go out of your way to engineer something that sounds a lot different from the crowd (which may or may not be a good thing), there's a lot of convergence doing on: different topologies, different chips, etc., end up with a sound that is really pretty similar--and which is only picked apart by audio reviewers looking for something to hang their hat on.
