@PeteS - Hmm tricky this, allsorts of things affect strummed guitar, you probably have a sound you want me to n your minds eye, and getting it might be a way away from what you expect to need to get it, for example I used to have a cheap yamaha fg-160 which was my goto strumming guitar but was a terrible picking axe…
New strings a couple of days old to stretch out, so they don’t move out of perfect tune.(had a nightmare session once with out of the packet strings)
Where the track will sit in the mix is also a factor, if it’s exposed then I might play or use a slightly different technique mic wise, i do tend to use a thin-ish plectrum when recording a strummed guitar it gives it more of a pleasant feel to it. I love the beginning of Take That’s Greatest Day, that’s the strum sound I’m often after or Faith by George Michael…
After testing about 10 mic setups Mid side condensers came out the best.
If you have one mic I’d strongly suggest taking a very methodical approach, changing only one thing at a time, try and keep the playing the same , move the mic distance away, if it has an 80hz roll off switch to see if that works, Position is key not too close and as Paul says super tidy playing, leave off any eq and verb till you’re happy with the recording, the subsequent processing will be obvious.
The testing will be money in the bank when you come to do it again, write down each each test and what the results were…I did it (took maybe 3 hours) and never have to guess when tracking acoustic guitars.
How many tracks to use? Well how Many are there on Big Yellow Taxi by Joni Mitchell, she played a Martin D45, now they are good strumming guitars.
Hope this helps Pete, beat of luck and let
Me know what you do…