Silverstone

For the most part, a neutral, flat, or near-flat EQ curve is best to let your speakers (and/or crossovers) do the work. Many times, this may present an overly warm sound. If this is undesirable or your speakers are extremely present with mids, drop the mids from 500k to 2000k down one to three dB.

In my experiences, when using lower-to-mid tier speakers, this turns out decent. I'm not a fan of gaining dB in any frequency, however. A common problem is when someone becomes too familiar with bass and treble boosted music, giving them a distorted taste of how all their music should sound.

With higher end systems, utilizing amplifiers and components that play well with each other, you'll find all my EQs are flat. Door speakers are mids. If you want more bass, add a small subwoofer. The tweeters will handle higher frequencies. Mids should not be expected to play well below 50hz. If you're seeking more bass, remember this: you're supposed to hear the bass, not the sounds of the speaker moving or peaking.

My $.02.

In the end, while someone may tell you what the "correct" EQ setting will be, everything depends on what's pleasing to your ears.