Hi! newbie here, so the following should be read in that light
. This applies to solo guitar recording in particular.
I've been recording Martins and Gibsons for nigh on 25 years as a musician (only 3 of which were professional
). This was by and large in studios in Londnon and only latterly in my own setup in Scotland. I tend not to fuss or obsess about the niceties (any more), but 3 fundementals are non-negotiable.
1. A fine guitar. I use a Martin OM-18 these days (small body, mahogony. Lots of snap and oomph.)
2. An acceptable room. This means for me broadband absorption to tame room modes.
3 No phase issues. Any spaced mic techique has phase issues to my ears now. The so-called 3 to 1 rule is not good enough so it's X/Y or mid-side for me. X/Y is my go-to with SDCs - about 18" pointing at the dovetail joint. An additional important advantage of coincident mics is that the guitar image is not 20 foot wide on playback. These things are 3 foot wide?
The above are inviolate and if I follow them I get realistic guitar recordings - not a splashy, muddy or mushy mess.
Guitar set-up is more important than the age of strings (within reason). A guitar with a medioce set-up will have intonation problems to some degree, may be difficult to play cleanly, and may even fret-buzz to an unmusical degree. Tuning machines my even resonate on certain notes.
Stuff like EQ, compression and reverb are a matter of taste and aesthetic during the mix. But while they are more often employed than not, it's with a light hand.
As to the quality of mics and preamps; as important as they are, I assert that they are second-order considerations.
So, to repeat:
Guitar.. room.. coincident mics.
Thanks and regards.
Dave