If you peruse the things that Frank Van Alstine said in the previous century, one of the gems you might find is his view that audio gear shouldn't re-interpret an artist's intent. Rather, it should function as a perfect copy machine. Others have referred to this philosophy as "straight wire with gain."

I believe Frank needed to emphasize this at the time largely because of the increasing fashionability of single-ended class A tube power amps -- which as a rule came with with low linearity and high output impedance. The occasionally pleasant effect this combination can create became a marketing lever for many manufacturers. "Warm. Rich." Buzzwords for a loose low end and signal masking. What they never said was, "Not as the artist intended." Nor, "Works great for some stuff, not so much on others."