That's why so many mixes end up sounding muddy. All the instruments occupy that same space between 100 - 250
Hz.
So unless your acoustic guitar sound sounds really thin and weak, I suggest cutting in that area. Cuts in your acoustic guitar EQ in the lower-mids add subjective boosts to the higher mids, giving your acoustic guitar more presence.
Also, if you pointed your microphone at the sound-hole when you recorded your acoustic guitar it might sound pretty boomy. Cutting at 200 Hz can fix that boomy acoustic sound.
Body
Sweeping around this area is helpful if you need a little extra body to your acoustic guitar sound. Small boosts can add the extra weight to your acoustic guitar, especially when the lower frequencies only add mud and boominess.
"Cheap Sound"
This is not in the picture but it's worth mentioning. Cut in the area around 800 Hz to get rid of that cheap string sound you
hear on inexpensive acoustic guitars. A narrow cut in the acoustic guitar EQ there can really smooth out the sound.
Presence
Once you cut the lower-mids, you don't always have to boost the higher mids to add presence. There's enough presence by just adding a little extra volume to compensate for your low-mid cuts.
However, if your acoustic is still sounding a little dull, a broad boost in the area between
2 - 5 kHz can add some more brightness and attack. I would actually recommend going all the way up to 8 kHz for that extra brilliance to your strings if you like that sort of sound.
Air
For just an overall facelift to your acoustic guitar sound, add some air with the highest frequencies. I recommend restringing your acoustic often so that the strings don't lose their brilliance, but if you need to add some extra sheen to them, here's where you go.
Easy Acoustic Guitar EQ
Remember theses simple guidelines the next time you slap your EQ on that acoustic guitar track. It's a simple and easy way to navigate the frequency spectrum of your acoustic and results in a better
acoustic guitar sound.
If you'd like more help with acoustic guitar EQ, or how to EQ any instrument in particular, check out EQ Strategies - Your Ultimate Guide to EQ. It's the only guide you
need to help you use EQ to make crystal clear mixes from your recordings.