How can this guitar stay in tune?
 

My Martin OMC-15 seems to never go out of tune. My humidity went from 60% to 40% this weekend and I didn’t have to make any tuning adjustments? How is that possible? My other guitars seem to go out of tune with just a 5% difference.

I will be looking forward to the replies on this question. A previous thread last week claimed that Mahogany top guitars crack less.

My spruce topped guitars most certainly go to the plus or negative side of tuning, with small humidity changes.

Just to even out the spectrum on these things, my 000-15 usually needs the tuning tweaked if it's been a few days.

Those open gear tuners are really good.

If I have a temperature flux in the house though, I've never met a guitar that doesn't go a little out of tune. I'd say you got lucky.

I think so. It kind of shocked me.

Sometimes after a change in humidity or temperature I find that the entire guitar has drifted sharp or flat so that it is still in tune with itself. If I check with a tuner though, all the strings are off, but apparently by the same amount. Depending on what I am doing, I just leave well enough alone and hope the it goes back to where it was when the weather changes again!

Rosewood,
Curious. What method (electronic tuner, ear or tuning-fork) are you using to make the call?

Same one I’ve been using for years. D’Addario tuner. Plus, it just sounds In tune as well.

Huh. How about that!
-I swear, even in my reasonably controlled upstairs music room, if someone gets a drink of water in the kitchen or turns on a light or if someone boils an egg, the added temp/humidity forces me to slightly tune!

I am curious how long it was at 60% and 40%.

60% for two weeks and between 40 and 45% in the last two days. This has been the second day and that’s when I picked up the guitar to play. I even checked my hydrometer to make sure it was correct. Still amazes me. Every one of my other guitars needed to be retuned.

Rosewood99, this guitar top is Mahogany correct?

That is correct.

The letter 'C' in OMC-15 stands for ... concrete.

I hardly ever have to tune my Martin CEO-7. I live in Sweden with dry winters. Maybe the secret is not to change strings every year 🤪