Accuracy is a man made term that has nothing to do with how the brain listens to music. In fact, being a term conceived in the right brain, accuracy can have little influence other than to cloud the perception of music. Why? Because experiencing music is a function of the Left brain. Trying to use the left brain and right brain at the same time is often to use either with less results.
That said, when man applies the term "accuracy" to music reproduction he is assuming his definition of accuracy is correct and regrettably it is too crude and simplified to be even close. All math and standard practices for designing and measuring amplifiers looks at crude indicators of performance and "accuracy" while overlooking all of the embedded or underlying subtleties hiding in those measurements or beyond those measurements ability to reach.
This is why it is perfectly acceptable practice in the professional world of amplifier design to group both odd and even order distortion in the same camp and why it's also perfectly acceptable to diminish timing cues in the music with negative feedback.
I don't really like the rather simplified and crude application of the word distortion to "harmonics" as in "Even order harmonic distortion". I'll accept it for "odd order harmonic distortion". The reason is simple; In nature sounds are richly embedded with even order harmonics. The harmonics are mathematical. They exist to add GREAT complexity to an otherwise simple fundamental note of sound. Put another way, they take a fundamental sound that contains X amount of data and multiplies the data by a factor of thousands. This way the ears of the world can discern massive amounts of information from that sound, an evolution of survival.
Odd order harmonics on the other hand, which are an artifact of some amplifier designs, are seldom found in nature and therefor sound artificial.
Many people will tell you that SET amps add a tremendous amount of distortion that is not really there in the recording and that solid state amps have some 10 to 100 times less.
The truth is in the crude misuse of the word distortion. If an analog recording is rich with even order harmonics (things that define the timbre and space of instruments) then an amplifier design that cancels even order harmonic distortion is going to be less adept at reproducing even order harmonics in the recording. Plus, virtually MOST amps that cancel even order harmonic distortion, ie, push pull topologies, also require negative feedback which destroys timing cues and as a result smears detail and collapses depth of sound stage.
So in summary, the exact opposite of common belief is true: SET amplifiers take away FAR LESS information from the original recording than do push pull or solid state. It's EASY to hear. A 3 year old can hear it, and so can you. Why then do most amplifier designers apparently not use their ears? Because they in fact don't use their ears, instead they use calculators and their eyes to view their scopes until it looks right according to standard schooling in electrical engineering. Sad, but true.
It's really just that simple