Humidity Check... it's that time of year again.

Bob Holo

Humidity check time. I was playing a bit today and was thinking: "Damn, I like the finish job on this one, it really shows the grain of the top" .... and yet it seemed to play a little low & "slappy"... and then I noticed that I could feel the fret ends just a little. Hmmm....

Well... it's that time of year, folks.

- If the grain on your soundboard is more visible than it usually is...

- If your action seems a little low or somehow your guitar just sounds a bit more buzzy or metallic or less powerful than it usually does...

- If you can feel your fret ends...

Then you need to humidify. It'll help the sound of your guitar, the playability of your guitar, and it'll make it more resistant to the types of problems that low humidity causes... popped frets... popped glue joints... cracks... all that nasty stuff that costs you time and money and inconvenience; and that shortens the life of your guitar.

Phil

Hey Bob - thanks for the reminder. Does using a humidifier apply to mainly newer guitars as opposed to my 30yr old Anastasio or does it apply to all guitars the same?

cheers

Phil

Michael Bauer

Bob, I've heard many thoughts on the preferred humidity for guitars, generally anywhere between 40-50%. I've always tried to keep it between 45-50%, but right now even 40% is hard to maintain with a humidifier running 24/7. In fact, 42% is about as good as I am getting in the Chicago desert this time of year.

Do you have any thoughts on the best humidity for gypsy guitars? And how much humidity is too much? I've never gotten a good answer to that question.

BTW, thanks so much for all you thoughts and suggestions regarding the Busato. The work on the neck is beginning this week. We'll see where we end up. I'm just hoping the heat doesn't mess with the lamination.

Bob Holo

Well... you hear this a lot - that older guitars are less susceptible to humidity swings. It's true that they are, to a certain degree, more stable, but most of that has to do with reduction of internal stress and fiber compression and glue/finish hardening etc.

I mean, sure... over centuries, wood becomes less hygrosopic as the glycols in the hemicellulose oxidize and bond less readily with hydrogen, but reasonable humidity is still important for a lot of reasons - glues - finish - joints between different materials... Lots of things absorb water. Hell, even nylon has a hygroscopic expansion coefficient. It's like Stephane Wrembel says: "Water is life, man!"

So yes, definitely - all guitars should be kept properly humidified.

40 to 50% is a good range. If you can only manage 42, then go for 42... as that's much much better than 32...

noodlenot

Bob Holo wrote:

I mean, sure... over centuries, wood becomes less hygrosopic as the glycols in the hemicellulose oxidize and bond less readily with hydrogen, but reasonable humidity is still important for a lot of reasons - glues - finish - joints between different materials...

I´ll try to take advantage of your presence here , and ask: hemicellulose (degradable) has been linked with the hygroscopic behaviour of wood (and long-term "opening-up" of instruments), but surely cellulose (quite stable) also has a role, right? after all it makes for about half the weight of dried wood and has two free hydroxyl groups per monomer... or is it "too much" linked to hemicellulose, and so its -OH groups are of more difficult access? anyway, after degradation of the hemicellulose polymers, wood will continue to be hygroscopic due to the -OH groups of the glucose monomers, right?

noodlenot

oh yes, thanks in advance!

Bob Holo

Yeah... absolutely. wood never really stops absorbing water entirely unless you encase it or impregnate or modify it. I believe there are certain alcohols that you can use to modify lignin and cellulose and essentially polymerize / cross-link them. As to whether you'd still call the result wood... I don't know. Modified and designer materials are likely to be among the biggest thrusts of the next couple of decades but the specialized knowledge required to keep up on all that is fairly intense and so I don't delve into it more than I need to in order to get the right strength / mass / anistropy for my purposes. But it's a huge area of coming development. If I had multiple lives to live... who knows. But again, it's just too big a field to keep up on unless you're doing it full-time so I skirt around its edges and glean what I need to for my purposes and otherwise just feel grateful that there are a lot of smart people driving it forward.

So.. you're right - cellulose isn't made up of carbohydrates etc... so it's a little more stable than hemicellulose - but cellulose breaks down too. I think it actually hydrolizes instead of oxidizes though... or maybe both. Haha... again... "I only learns what I needs to learns..." but I think part of it converts to an acid... which is why its good to remove old pickguards when they start to discolor and look like they have a white fungus & etc...

Anyway - I'm not a chemist, so don't use what I say in a research paper (lol) but yes, wood retains the ability to absorb water for a looooong time...

...which is yet another reason to keep your instruments humidified... ;-) (right?)

noodlenot

Thanks for the reply (it was a bit off-topic)!
BTW, i´m a chemist and i have to struggle a lot to keep up with much less... a guy just tends focus on what´s meaningful to him, i guess...

cheers,
miguel.

thetoneblasters

What is the best way to humidify a guitar?

ViperMad77

thetoneblasters wrote:

What is the best way to humidify a guitar?

I have used the planet waves instrument humidifiers.
here's a link.. http://tinyurl.com/7ozdrym

-if there is something better out there i'd like to know.

@Bob - is there a particular humidifier you use/prefer/suggest?

Il Trovatore

I live in California, the San Jose more specifically. It has been barely dipping into the forties at night and the humidity today (via the weather channel) was 85%. Is a humidifier even something I need to invest in? My skin has been feeling drier but my guitar lives in its case in my house.
I just wonder if I am doing something wrong and not worried about sounding stupid...