If I really get it as close as I can to reality on a wide range of records in the set-up process, I don’t mess with it. Sure, there will be variations in recordings, and if you are of a mind, you can buy a very high quality equalization (analog) unit to play with such adjustments. In gross, I think there is a big difference between reproducing music and soundtracks for movies, and the latter demand "shuttle lift off" capability. I remember watching people’s primal reactions in a large scale home theatre I ran back in the early ’90s. T-Rex stomping -- the audience would be squirming in their chairs--is a little different than Cecil McBee playing double stops on a bowed bass. But, you really have the ability to do what you want---the cheaper "pro" gear is not necessarily something I’d want to put into a system, and it’s been years since I heard the Cello Pallete so I don’t know how well that stands up today, but I suspect you can find some high end parametric equalizers if you want to twirl knobs. I’m not trying to be dismissive about it; it is a fair question, but optimally, I guess you’d be adjusting things based on program material and not shortcomings in the playback system.
A lot of what is considered "bass" isn’t super deep. And to my ears, a lot of what defines lifelike bass isn’t just the ability to reproduce the lowest fundamental, but the harmonics and decay behavior of something like a well-recorded concert grand or well-mic’d double bass. If that isn’t on the recording because of how it was made, EQ after the fact that it is "locked" isn’t going to suddenly provide it; you’ll be placing greater emphasis on part of the range of sound, but not installing ambience, or affecting decay (I caveat this knowing some folks have multitrack capability and can do just that, but for the average home consumer even with some serious "audiophile" gear, it isn’t possible). You can’t create what isn’t there. (Well, an engineer can, and that’s what they do- manipulate the sound considerably in some cases to make it sound "natural"). Manipulating only at the subwoofer level is even more limited. I’d worry more about overall coherence and voicing, so you are hearing fully fleshed out instruments in the deep registers. And it coheres with the mids and high frequencies in balance.
If you are listening to hard rock or electronica, your priorities may be different--not wrong, just different. But, to nail down what a real piano sounds like (having one or two around in the house is helpful just as a reference), or double bass --(I come back to Cecil McBee only because he was generous in playing melodic lines that never interfered with the overall composition), there is a set up that will, with modest effort, give you a taste of reality on the the other side. At that point, and this is a strictly personal point of view, I don’t mess with something that sounds lifelike. That’s my baseline. You can also mess with VTA, but drive yourself mad particularly with cartridges that don’t seem to care much about the stylus rake angle or such other technical issues. You can go through a set up process using engineers, measurements, tools and computers, but the final arbiter, even if it is just a slight touch of arm elevation, or a modest change in crossover setting, may get you in the zone. But the final adjustments are made by "ear." And that’s where I stop. I don’t keep readjusting record by record; I personally think that way lies madness, but if you can handle it, go for it. More work. I adjust VTA on the fly only rarely, and only when there are truly gross differences in the nature of the disc thickness and how it was cut. I have also lived with cartridges that were far more sensitive to this particular adjustment, and others that are kind of agnostic. Get the arm height right and stuff snaps into focus.
To the extent the recording doesn’t deliver, twirl away. It will compensate, but not replace, a more authentic experience of the original performance under conditions that may simply not have existed when the recording was made; in other words, you can’t fix it "after the mix." You can do more gross adjustments, and also look for pressings (if you are an LP hound) that bring it closer. Sometimes, that’s the difference- the pressing and the mastering. One can be flat, dead and lifeless and no amount of fiddling on your end is going to change the source material; however, you can judiciously "juke" the sound to some degree. Me, I prefer to find the best sounding pressing of a given record and let it be. It’s sort of a very after the fact, after the mix, after the mastering, after the pressing attempt to crudely compensate for what the original recording lacks. If you listen to some of the Steve Wilson remixes of the old UK prog rock catalog, it’s immediately evident that Wilson’s preference for working in the digital realm is not a huge negative, given what he is able to pull off by going up-chain to the multitracks and actually remixing the album across the board. That you cannot do, as far as I know, at home, based on a two or even 5.1 recording. Others may take a different view.
Sorry for all the words, time- you know?
