Is 35-40% humidity acceptable?
 

I just got a new acoustic guitar and I want to make sure it's being handled properly.
My hygrometer reads between 35 and 40% humidity.
I did not a get a case with the guitar. I have one on order but it is showing a 2 month wait. It's an Epiphone Masterbilt EF-500R.
I ordered a soundhole humidifier which will be delivered on Tuesday.

So my 2nd questions is how often should I use the humidifier. The guitar is almost always on a stand.

Thanks
Len

40% is on the low side. I would use a humifier if the guitar must stay out but it take quite a bit to change the room's humidity. The case is the best bet with a humidifier.

Here's how Kevin Ryan sees it:

http://www.ryanguitars.com/NewsandEv...dity_Chart.htm

I wouldn't expose my guitars to anything lower than 40% for more than a day or two.

Larry, a regular on this forum and a pro has said he doesnt humidify his expensive guitars until 30%. I on the other hand put an Oasis in my Martin when it gets below 40%. Only because I dont want to find out what would happen.
I believe that different guitars have different tolerances depending on the design, what the RH was when it was built but other factors too. Nobody used to humidify guitars and there are some great guitars from the past that people with money have. I am guessing that there were ones that didnt survive due to a variety of factors including the above I listed.

Guitar humidity chart from Kevin Ryan's web site;

http://ryanguitars.com/NewsandEvents...dity_Chart.htm


"40%; OK

35%; Time to think about humidifying your guitar; the soundboard is starting to sink in; probably will be OK for a few days so don’t panic (yet!)"

I think guitar builders tend to be conservative because they want to avoid warranty claims (a totally reasonable stance). Museum curators responsible for instrument collections pretty consistently give 35% to 55% as the safe range, with 45% as an ideal. These are people who often have advanced degrees in conservation of various objects and who have responsibility for maintaining extremely valuable collections. So, I consider them highly credible.

Everyone has to make their own call but I personally wouldn't worry if the RH dipped a bit below 40% from time to time.

In the winter when the furnace comes on, I take a Zip-Lok sandwich bag, fold it a bunch of times, then cut slits in it with scissors. After this I cut a small dish washing sponge in half, soak it, then wring it out as much as possible-put it in the baggie, put it inside the guitar and fuggetiboutit. "Till the sponge is dry. Rinse and repeat.
I'm in Colorado... pretty dry. No problems so far.
Regards,
Les

I use the sponge in a soap dish humidifier and it works just fine. If you search on "soap dish" you might find a great thread from last year that provides a full pictorial of how to produce one. Pretty simple. Find nice cheap clear plastic soap dish (not the brittle kind), drill many holes in it, find bacterial-resistant sponge from supermarket, trim to fit, get it good and damp (not dripping) and pop it in the case.

Best if you can monitor case humidity with a hygrometer that you know is reasonably accurate. Some can be out by up to 5 degrees. I use 2 digital types and just kind of take an average, although the one put out by Vicks (yes, the Vicks Vaporub people) seems to be the most accurate. It measure both temp and humidity so it's perfect. You can often find these types at the Pharmacy - although mine came from a large home hardware type store.

This type only needs about 15-30 minutes to stabilize, so you can check the levels with the lid closed and be reasonably sure that your guitar will be just fine in it's little home.

I use this all year around - even in the humid summer months. Constant temp and humidity is the best.

For my peace of mind, 35 to 40 percent relative humidity is definitely in the acceptable range.

I would be more concerned with sudden large fluctuations in humidity than the actual value per se.

35 to 40 percent RH and keeping your guitars cased when not being played keeps me asleep at night ! :D

Guitars sound pretty darn good at that humidity level as well ! ;)

Harmonics101

I keep my guitars out on a stand in my music room, as well. And I use a cool mist room humidifier to keep the relative RH as close to 45-50% as possible, with the temperature at 70-72 F.

If the humidity level in the room drops to 40% or less, my guitars will start to buzz due to the lowered action -- especially the bigger wound strings. Guitars may sound better when drier, but the buzz is annoying, and I'm really too lazy to be using summer and winter saddles, not when I can more easily control the temperature and RH levels in the room. Nor do I want to be adjusting the truss rod and adding or lessening the relief. But that's just me ... I'd rather play than tinker around with keeping the bow in the neck at the optimal amount all year.

Of course, it's the "younger" guitar that is more susceptible to the seasonal fluctuation .. the older instrument is far more stable than the other.

50% RH at 72F seems to be optimal for the best playability and sound from my guitars, based around my preferred set-up and action. And maintaining 50% RH, in my house, and in my area (Western N.C), seems to require the least amount of humidifying/dehumidifying, which is easier on my power bill.

Sound hole humidifiers are for use in a case, not a stand. If you want to keep the guitar on a stand, a whole room humidifier is the better solution. Personally, I think a room humidifier is the better way to go in the first place, if you have a dedicated area to store your guitar.

35% RH is pushing it a bit, IMHO. Although as previously mentioned, it's the sudden changes in temp and humidity that are the most destructive.

... JT

What warranty claims would those be? EVERY builder that I know has an exclusion for humidity for their instrument.
I think you are correct that permanent damage will not occur at 35% but the folks in museums don't need the guitar to be playable. I'm guessing that most guitars will start buzzing at 35% if left there for very long.
Another thing to keep in mind that just because your hygrometer says 35% doesn't mean that it really is 35%. I bought 4 of them once and had four different readings that varied by 20%. Now, if it says 35% and is off by 20% you could be in BIG, BIG trouble. Learn how to calibrate it and do so, so you have a reliable reading. (btw, it makes no difference how much the hydrometer costs, the four I used were very expensive scientific ones. )

i guess i go a diff direction. have had guitars over 40 years and never have worried once about guitars and humidity if not below 30%. never once had a problem/

I pay good money for the same thing! :)

Here in NZ the average temperature is 12.5c (55 degree F) and the average humidity is 72.9% (from 67% - 78%). I leave my guitars on a stand all year round with no problems, but not in direct sunlight. Talking to staff in the local Rockshop they tell me that when importing instruments from overseas, it can take several weeks to open up a case and acclimatise the guitars.

Rosco