Anyone have their wood acoustic at 35% to 38% RH...

DHart · #1 08-11-2017, 01:42 AM

... for an extended period of time?

Have you seen any deleterious effects from this?

I know that 40% to 45% is recommended, but would 35% to 38% cause damage? Any first-hand experience with this?

chitz · #2 08-11-2017, 04:14 AM

I've had mine there for short periods of time (2-3 weeks) and that's where they sounded best.

If you change the RH gradually over a period of time, it "shouldn't" be of consequence. Still it's a roll of the dice. 40 is a good number.

BrunoBlack · #3 08-11-2017, 05:17 AM

My guitars are 35%-40% all winter and 50%-60% all summer.

#4 08-11-2017, 05:22 AM

Not sure if he's right but my guitar tech/luthier ( very experienced and very highly regarded ) told me that down to 30% rh is no problem.

CTGull · #5 08-11-2017, 05:25 AM

Quote:

Originally Posted by Haasome

My guitars are 35%-40% all winter and 50%-60% all summer.

I am the same. I run a big humidifier all winter putting out 3 gallons per day on average and many days it struggles to hit 40%. In the summer it rarely goes over 60%, closer to 50% with the air conditioner running.

I do put the all solid wood guitars away in cases (with home made sponge & perforated bag humidifiers) for the winter though and leave out something with just a solid top. Just in case.

Rev Roy · #6 08-11-2017, 05:43 AM

Even with a room humidifier running and Humidipaks in the cases my guitars stay at 35-40% RH during the heating season. Never had a problem with any of them. And they sound great at that RH level.

John K · #7 08-11-2017, 05:49 AM

Here in Norway there is around 40-45 during summer, but very dry during winter. I have a room humidifier, and it kicks in when it gets below 30. Been doing this for a decade, never a problem. And, yes, they sound good when between 30 and 40.

MichaelD23 · #8 08-11-2017, 05:50 AM

Though I live in the South, our houses can get quite dry in the wintertime when it's cold. My old D-35 suffered fretboard shrinkage and more than once I needed frets filed or adjusted due to that neglect. Wish I'd known better back in the day. Now I keep a humidifier and a dehumidifier at the ready, depending on the season and keep my guitars cased, with some sort of humidfier in the case during the dry season.

devellis · #9 08-11-2017, 08:10 AM

Back when I was more focused on mandolins, I acquired some pretty old instruments and felt that I needed to do some research on humidity. I found several publications from museum curators about how they stored their valuable wooden artifacts, including musical instruments. These people (a) are responsible for priceless objects and (b) have typically received advanced degrees related to the preservation of those objects. So they're highly credible in my book. Pretty much across the board of the stuff I found, the ideal RH was listed as 45% and the acceptable range was listed as 35% to 55%. So, based on that, I'd say that 35% to 38% shouldn't pose any problem.

Manufacturers often recommend something higher, like maybe 50%. That's well within the acceptable range and pretty close to the museum folks' "ideal." I think builders may trend slightly upward because they realize that a nominal RH may actually be somewhat inflated due to hygrometer inaccuracy, transient dry spells, etc. So, to avoid issues arising from excessive dryness (which is often worse than going a bit too high on RH), their recommendations skew a bit higher than the museum folks.

If you're confident that the 35% to 38% values are really pretty stable and things aren't drifting below those values for extended periods, you should be fine, based on the reading I've done.

DHart · #10 08-11-2017, 12:09 PM

Thanks for all the comments. My sense is that 35 to 38% should be humid enough to avoid real problems, provided of course that those hygrometer numbers are accurate and humidity doesn't drop much below that. I sometimes have as many as 6 different hygrometers in my walk-in guitar closet so I'm not relying on a single measurement. About 16 guitars (2 acoustic) are on stands in the closet (out of their cases) because I find that guitars in their cases don't often get played.

I have a small room humidifier in the guitar closet and I can keep the guitars at 45-50% if I really must, but I so much prefer how the acoustic guitars sound at around 37-38%, that's why I wanted to get this thread going and gain some input from others.

The electrics are all fine, of course, at 37-38%, but I do moisturize the raw rosewood finger boards once every year or two, with a very light application of fingerboard oil.

AZLiberty · #11 08-11-2017, 12:13 PM

You need to buy that Rainsong you have been thinking about.

Once you have one of them, refilling humidifiers constantly starts looking more and more like too much work.

DHart · #12 08-11-2017, 01:12 PM

Quote:

Originally Posted by AZLiberty

You need to buy that Rainsong you have been thinking about.

Once you have one of them, refilling humidifiers constantly starts looking more and more like too much work.

Ted and I have worked that out! RainSong CH OM 1100NS (previously known as the "Shorty") is on the way!

. 12-fret with short scale is what my Eastman E10 OO-Mahogany also has and I'm really liking that set-up. Shorty will be my RV travel guitar, as well. No qualms about taking it anywhere, indoors or outdoors.

That said, my Martin & Eastman won't be ignored - they are too awesome to be forsaken! So, the RainSong will live out and about at all times. The OM28V and E10 OO Hog will come out as desired and then return to the humidity controlled walk-in closet at night.

The humidifier in the guitar closet is on a timer, so it clicks on about 8 times a day, for about 10 minutes each time. I only have to add water to it every 10 days or so.

Earl49 · #13 08-11-2017, 01:28 PM

Congrats on pulling the Rainsong trigger. You won't be disappointed. I still like wood guitars (especially koa) but find myself reaching for the CF ones more often. With the exception of my all-koa Taylor 424, if they all disappeared I would only replace the carbon fiber ones.

Back to your original question: when during the winter I notice that my two room hygrometers read 34-38% I still leave them out but watch much closer for any signs of trouble -- like obvious top grain "printing through" the finish, sinking bridge / low action, the center seam starting to become visible, and similar symptoms. If any guitar seems to need it, that guitar goes into its case with a damp sponge for a week of spa treatment. But most of the time my house stays at 38-45% RH so I don't have to "fret" too much anymore.

DHart · #14 08-11-2017, 02:44 PM

Quote:

Originally Posted by Earl49

Congrats on pulling the Rainsong trigger. You won't be disappointed. I still like wood guitars (especially koa) but find myself reaching for the CF ones more often. With the exception of my all-koa Taylor 424, if they all disappeared I would only replace the carbon fiber ones.

Back to your original question: when during the winter I notice that my two room hygrometers read 34-38% I still leave them out but watch much closer for any signs of trouble -- like obvious top grain "printing through" the finish, sinking bridge / low action, the center seam starting to become visible, and similar symptoms. If any guitar seems to need it, that guitar goes into its case with a damp sponge for a week of spa treatment. But most of the time my house stays at 38-45% RH so I don't have to "fret" too much anymore.

Yes! The only "fretting" you want going on is with the fingers of your left hand! It's good to hear that you've generally had no problems with 34-38%.

If all of my guitars were gone, I would want to replace the OM-28V and the Eastman E10 OO Hog. And I'm sure I'd want to replace the RainSong.

Among my electric guitars, I have quite a few, but would likely only replace three or four of them.

I think I'm going to continue maintaining about 37-38% in my guitar closet - while keeping an eye out for any tell-tale signs of a need for "spa treatment". I only have the Martin and the Eastman to have to keep an eye on with regard to humidity.

valleyguy · #15 08-11-2017, 02:46 PM

I see your in Phoenix. I live in L.A. We both have dry climates. I put mine in a case with humidifier when it gets below 20%, which only happens with Santa Ana winds and lasts for a few days.. I rarely see anything over 50%.

In my unscientific opinion, I think wide changes are the problem. Once the wood acclimates to a 30%, a short spurt to 20% isn't all bad, as a increase to 40%. I'd say in humid climates say in the southeast, when you have the guitar going down to 20% in the winter because of heat, I'd be concerned.

But, all IMHO

I also think a dryer guitar sounds better.

Oh, and I've never experienced cracking, or fret problems regularly running at 30%. In fact I have 3 guitars that are ALWAYS hanging on the wall, my "beaters" and they seem none the worse for wear, sitting in 12% humidity for days on end.

I also have some 100 year old rosewood furniture from my grandparents in Brazil that I don't humidify. They have been in incredible humidity in Brazil and Venezuela, and incredible dryness in San Diego, L.A. and in the northern deserts of Mexico. One piece has a small crack and one shelf is warped, but otherwise OK. This furniture will hopefully provide some guitar maker some fine wood someday when I pass, as my kids have no interest in having them.