Myself, I am both, when the engineering hat is on I want to know what creates what sound, how to find the problem, what to do about it, and so on. Can very delicate DSP fix the problem? Is there noise being injected somewhere? Is the postion wrong? Is the amp picking up vibrations and thus having problems (if the amp is solid stated and doing that, and its not on a paint shaker, replace it). Is the phono stage doing its job...so on and so on. Measurement helps to track all this down, and to make a clear path. It is not the final arbiter though. It just lets you know what is changing as you make your mods.
Spin the hat around when the work is done and ,like jcarcopo, it has to be an emotional event, or why bother? That's the final test. Though I do have to admit I have to wait an hour or two between mental states, before just listening for pleasure.