Humidity and good acoustic guitars

DevonChris

digitalkettle said:

It sounds like, potentially, your humidity is too high...so I'm not sure you need to humidify the case...certainly something I've never done. Get a digital hygrometer so you can get an idea of where you're at...mainly for peace of mind.

Will do. Thanks. They're only about £10 on Amazon. Do you know what reading would be too high?
Cheers

digitalkettle

DevonChris said:

digitalkettle said:

It sounds like, potentially, your humidity is too high...so I'm not sure you need to humidify the case...certainly something I've never done. Get a digital hygrometer so you can get an idea of where you're at...mainly for peace of mind.

Will do. Thanks. They're only about £10 on Amazon. Do you know what reading would be too high?
Cheers

Somewhere between 50-60% is ideal...a cheap gauge will only give you a rough idea...it usually aligns with common sense, e.g. dry windy day or snowy with the heating on = low humidity...warm rainy day = high humidity...etc. Too high? I'm not sure but it might be the day your guitar starts sounding/feeling less lively. I don't overthink it.

My house is old and temperature swings in colder months...I run a dehumidifier most of the time just to stay on top of things.

I've got a couple of acoustics out on stands at the moment as I'm lazy and temperature is fairly steady 24/7...once that changes, they go in cases. One's a classical and one's a steel string...I've only had the truss rod adjusted once or twice after a rare trip to a tech.

DevonChris

Thank you, @digitalkettle I've ordered a digital hygrometer now so it'll be interesting to see what our actual levels are.

crunchman

The big problem is normally when the air gets too dry in winter.

Relative humidity is dependent on air temperature.  Hot air can hold a lot more water than cold air.  In winter this means that there is a lot less water vapour in the air.

If you take that cold air with less moisture content, and heat it with central heating you can end up with very low relative humidity indoors in the winter.  That is normally what causes issues with cracking.

It is very dependent on the difference in temperature between inside and outside.  In Devon, it's surrounded by warmer sea water in winter so it doesn't get silly cold.  As long as you don't run your central heating at a ridiculously high  temperature you should be fine.

DevonChris

Thanks, @crunchman, for such a detailed comment. You are correct about the weather in Devon and the effect of the sea on keeping an even temperature - it very rarely snows here.

I received the hygrometer from Amazon today and it showed 63% humidity at 22 degrees C this afternoon. That is probably a bit higher than the average modern home in the UK, but I don't think it is cause for concern.

As you and others have said, it is the lack of humidity and the change in temperatures that damage acoustic guitars.

Teyeplayer

Just noticed this in the classifieds and thought it might be of interest to you as you'd mentioned a furch:
http://thefretboard.co.uk/discussion/111770/fs-furch-stonebridge-d22-cm-and-schertler-amplifier#latest

fishfingers

@crunchman, is quite right - I've used several digital hygrometers over the years in my northwest Victorian semi. 50-65% in summer and down to 35% in winter when the central heating is on. I have had a crack through humidity problems with one guitar, but that was while living in NZ!

guycp

Our house (old granite farmhouse in far West of Cornwall) always has high humidity! A wet summer is worse. Currently at 78% in my office/music room.
I have had Bourgeois, Martins, and Gibsons and Santa Cruz that have been adversely affected by high humidity. Higher humidity is not normally a problem for cheaper heavier braced or laminated acoustic guitars, but can be a big problem for hand built guitars that were built in workshops with 35 -45% humidity (i.e. many hand made high end acoustics made in the USA). Not only do the tops swell up altering the action and distorting the top around the bridge, but the guitars loose their tone and can become woolly and dead sounding.
Best to get a decent de-humidifier and put it in the same room as the guitars and keep the door shut. I do this and manage to keep the humidity down to around 60%. I also use re-useable cotton bags of silica in each guitar case, which change colour when wet.
I've found that the best option for damp conditions is to have a room with a dehumidifier that you store your guitars in.
Also get a decent hydrometer so you can keep an eye on the humidity level.
Low humidity is not normally a problem in the UK

digitalkettle

guycp said:

Also get a decent hydrometer so you can keep an eye on the humidity level.

Hy*g*rometer!

Lewy

guycp said:

Our house (old granite farmhouse in far West of Cornwall) always has high humidity! A wet summer is worse. Currently at 78% in my office/music room.
I have had Bourgeois, Martins, and Gibsons and Santa Cruz that have been adversely affected by high humidity. Higher humidity is not normally a problem for cheaper heavier braced or laminated acoustic guitars, but can be a big problem for hand built guitars that were built in workshops with 35 -45% humidity (i.e. many hand made high end acoustics made in the USA). Not only do the tops swell up altering the action and distorting the top around the bridge, but the guitars loose their tone and can become woolly and dead sounding.

My experience exactly.

DevonChris

Teyeplayer said:

Just noticed this in the classifieds and thought it might be of interest to you as you'd mentioned a furch:
http://thefretboard.co.uk/discussion/111770/fs-furch-stonebridge-d22-cm-and-schertler-amplifier#latest

Thanks for your heads up, which I've just noticed! (my fault).

I saw that Furch for sale, but it went very quickly, unfortunately.

guycp said:

Our house (old granite farmhouse in far West of Cornwall) always has high humidity! A wet summer is worse. Currently at 78% in my office/music room.
I have had Bourgeois, Martins, and Gibsons and Santa Cruz that have been adversely affected by high humidity. Higher humidity is not normally a problem for cheaper heavier braced or laminated acoustic guitars, but can be a big problem for hand built guitars that were built in workshops with 35 -45% humidity (i.e. many hand made high end acoustics made in the USA). Not only do the tops swell up altering the action and distorting the top around the bridge, but the guitars loose their tone and can become woolly and dead sounding.
Best to get a decent de-humidifier and put it in the same room as the guitars and keep the door shut. I do this and manage to keep the humidity down to around 60%. I also use re-useable cotton bags of silica in each guitar case, which change colour when wet.
I've found that the best option for damp conditions is to have a room with a dehumidifier that you store your guitars in.
Also get a decent hydrometer so you can keep an eye on the humidity level.
Low humidity is not normally a problem in the UK

Thanks for your excellent comment, @guycp ; With all the wet weather we've had recently our hygrometer is currently showing 70 - 76% humidity levels. Not good.

Thanks for your advice about a dehumidifier and the silica bags. I am really tempted to get a high end acoustic, but would hate to see it experience those issues that you mentioned. I might have a chat with Mansons in Exeter to get their views on this too.

Fantastic help and advice from everyone in this thread. Thanks.
 

Adji

Some great advice already in this thread.

A de-humidifier and hygrometer is essential imo.

It is a little 'gadgety' but we have a pretty cool digital hygrometer (amongst other things) that links to your phone so you can monitor remotely.
http://www.planetwaves.com/pwProductDetail.Page?ActiveID=4115&productid=1074&productname=Humiditrak___Bluetooth_Humidity_and_Temperature_Sensor

I sometimes do some very basic workshops on maintaining acoustic instruments and touch on humidity.
IIRC the average humidity varies between about 60 and 80 per cent in the UK so low humidity is likely not going to be an issue THAT often.

Here are some findings from research I have done (including speaking to luthiers) on some of the problems that humidity can cause, it might be useful:

----------

Melting Glue

Excessive heat, resulting in low humidity / heavy moisture loss, could cause the glue to weaken or literally melt in your instrument.

  The results can vary from a slightly ‘sliding’ bridge to cracks in the guitar where the soundboard joins to the sides. Or, in extreme situations, the entire soundboard can be pulled away from the body of the guitar.

  It can also adversely effect other parts of the guitar, the frets may become loose in their slots and start to come out of the guitar.

Swollen Top

  The top / soundboard of your acoustic guitar should be flat (unless specifically designed not to be). A swollen or bulging top usually indicates there is too much moisture in the wood (due to high humidity) and the wood has   literally swollen. Often next comes cracking at the glue joints.

Sharp Fret Ends

  Sharp fret ends can be a sign of a guitar that is too dry. The neck / fretboard has become so dry that it has started to shrink or contract, leaving the metal fret ends exposed.

Sunken Top

  In direct opposition to the swollen top, a sunken top suggests that the soundboard is too dry and the wood has started to shrink. It is very likely that if you can spot this on your guitar, cracking or breaking at the glued joints is not   far away.

“Loss of Tone”

  Tone is incredibly subjective so this should not be the only defining factor.

  An overly dry guitar is often said to sound brittle, tinny, or thin.

  An overly wet guitar is often said to sound tubby, muddy or flubby.

Lewy

Adji said:

Some great advice already in this thread.

A de-humidifier and hygrometer is essential imo.

It is a little 'gadgety' but we have a pretty cool digital hygrometer (amongst other things) that links to your phone so you can monitor remotely.
http://www.planetwaves.com/pwProductDetail.Page?ActiveID=4115&productid=1074&productname=Humiditrak___Bluetooth_Humidity_and_Temperature_Sensor

I sometimes do some very basic workshops on maintaining acoustic instruments and touch on humidity.
IIRC the average humidity varies between about 60 and 80 per cent in the UK so low humidity is likely not going to be an issue THAT often.

Here are some findings from research I have done (including speaking to luthiers) on some of the problems that humidity can cause, it might be useful:

----------

Melting Glue

Excessive heat, resulting in low humidity / heavy moisture loss, could cause the glue to weaken or literally melt in your instrument.

  The results can vary from a slightly ‘sliding’ bridge to cracks in the guitar where the soundboard joins to the sides. Or, in extreme situations, the entire soundboard can be pulled away from the body of the guitar.

  It can also adversely effect other parts of the guitar, the frets may become loose in their slots and start to come out of the guitar.

Swollen Top

  The top / soundboard of your acoustic guitar should be flat (unless specifically designed not to be). A swollen or bulging top usually indicates there is too much moisture in the wood (due to high humidity) and the wood has   literally swollen. Often next comes cracking at the glue joints.

Sharp Fret Ends

  Sharp fret ends can be a sign of a guitar that is too dry. The neck / fretboard has become so dry that it has started to shrink or contract, leaving the metal fret ends exposed.

Sunken Top

  In direct opposition to the swollen top, a sunken top suggests that the soundboard is too dry and the wood has started to shrink. It is very likely that if you can spot this on your guitar, cracking or breaking at the glued joints is not   far away.

“Loss of Tone”

  Tone is incredibly subjective so this should not be the only defining factor.

  An overly dry guitar is often said to sound brittle, tinny, or thin.

  An overly wet guitar is often said to sound tubby, muddy or flubby.

Great info (although I slightly disagree that an acoustic soundboard should be dead flat...I subscribe to the opinion that no belly at all is the hallmark of an over-braced guitar )

I can vouch for the Humiditrak, it's a great bit of kit and the app is very good. I've been able to evaluate exactly how much protection my cases give to fluctuations in temperature and humidity and it's meant I haven't had to worry about it. 

DevonChris

Thanks @Adji and @Lewy

Our humdity today is 63% so it looks like we are bouncing around the 60 - 80% range.  That Humiditrak looks great. I guess you keep it in your guitar case (along with the guitar of course!) and monitor it remotely using your phone.

Are there any ideal humidy ranges that we should be trying to achieve to prevent damage to a top end guitar?

Lewy

DevonChris said:

Thanks @Adji and @Lewy

Our humdity today is 63% so it looks like we are bouncing around the 60 - 80% range.  That Humiditrak looks great. I guess you keep it in your guitar case (along with the guitar of course!) and monitor it remotely using your phone.

Are there any ideal humidy ranges that we should be trying to achieve to prevent damage to a top end guitar?

All my opinion....

There's damage, and there's sub-optimal performance.

For damage, I think there's a floor of about 40-45% RH that you want to make sure you don't go below for any length of time. The ceiling is quite high - your guitar is probably not going to sustain actual structural damage until it's living well above 60% RH all the time, and then you'll possibly still be fine (as others have reported here).

But a typical high end US -built guitar won't be playing or sounding it's best up there. The top may belly significantly, meaning that to improve playability you need to lower the saddle. That's fine, except that affects a critical bit of guitar geometry...the height of the strings off the soundboard. People don't talk about this much but it's really important to getting the most out of a good guitar. It affects the way torque is applied to the top and therefore the volume and response of the guitar. The ideal is generally about 1/2" distance between the bottom of your low E string and the soundboard right in front of the bridge. Now, if you have to drop your saddle to restore playability (because excess humidity has caused an excess belly), then the more you drop that string height off the soundboard, the more you're deviating from how that guitar was built/braced/voiced to work. So that's one thing. Another is the fact that over-humidified guitars can sound woolly/muffled and it can all feel like a bit of an effort. Chances are, what attracted you to a high end guitar in the first place is the way the notes seemed to literally spring out of it. Wet guitars tend not to sound or feel like that.

As I say, it affects different guitars in different ways. My Collings guitars sound and feel best at 45% RH, I can tell a difference if they've been around 55% RH for any more than a day or so. No chance of damage there, but they're not the guitars they can be above there (or the ones I incurred significant debt to acquire!). For the sake of a couple of hundred quid on a good dehumidifier, why settle?

Of course you can't keep guitars in a controlled environment all the time. I take mine out to festivals where they'll be in a cold tent at night and probably be around a campfire etc. Who knows what the humidity is in a pub or club I'm playing at, and what would I do about it if I did know? But I can control where they spend most of their time and that's worth the effort as far as I'm concerned.

EDIT: Sorry, and yes that's precisely how the Humiditrak works.

DevonChris

Chances are, what attracted you to a high end guitar in the first place is the way the notes seemed to literally spring out of it. Wet guitars tend not to sound or feel like that.

Definitely.

I haven't bought an acoustic yet, but a bit of me is wondering if I'd be better buying a Yamaha LL16 level guitar rather than going further up market, though I've no issue buying another de-humidifier for the room where I'd keep the acoustic (in its case with a Humiditrak).

I think I'll give Brook Guitars a ring tomorrow as they are based about 10 miles from me and their humidity levels will be just as high, if not higher, than ours.

@Lewy - great information in your comment. Thanks very much.

Lewy

A good case will be sufficiently sealed to mean you won't need to run the dehumidifier while the guitar's in the case, by the way. 

For example, unchecked the RH in my music room regularly gets up around 60% if I don't run the dehumidifier. The inside of my cases rarely gets above 50% regardless of what's going on outside. The dehumidifier only takes 5 mins or so to get the RH down so I just run it for a bit before I settle down for a play. 

ToneControl

Assuming you keep guitars away from radiators, fires and sunny windows (many don't):

in modern UK houses, the only problem is low humidity in the winter, it can drop to under 30%
over 65% is dodgy too

I'd recommend buying 2 or 3 cheap hygrometers and trying them around the house
you may find one room not as damp during damp periods, e.g. an airy room that does not have much of an exposed external wall

Humidity will be determined by your house construction, not geographical location in the UK, the reasons are down to physics, and I will skip them since they are already on this forum in other posts

It may be that you need a winter room for guitars, and a summer one

a cello has a very different design to a guitar
top-brand acoustic guitars are very sensitive to humidity, and they can be hard to play, as well as sounding worse.
more extreme variations can cause damage, as noted, but normal variations will diminish the pleasure by putting the guitar out of tuning and changing the action, as the neck varies from one week to the next

In my house, the only risk is low humidity
Therefore I have 2 humidifiers, driven by a hygrostat, which switches them on below 45% RH
It's the size of a mains-socket-timer, with a UK plug socket on the front

They have another mode, which is intended for your problem, where they would switch on a dehumidifier above a certain humidity level (e.g. 55%)  
I'd recommend one of these for you. Tracking humidity is not as effective as controlling it.
If you get it right, you can leave the guitar out of its case all the time, and play it more

ToneControl

For good value excellent UK-made guitars, I'd recommend Avalon, ring up the workshop, since all the dealers are outside the UK

Adji

Lewy said:

Adji said:

Some great advice already in this thread.

Great info (although I slightly disagree that an acoustic soundboard should be dead flat...I subscribe to the opinion that no belly at all is the hallmark of an over-braced guitar )

I can vouch for the Humiditrak, it's a great bit of kit and the app is very good. I've been able to evaluate exactly how much protection my cases give to fluctuations in temperature and humidity and it's meant I haven't had to worry about it. 

Glad it works for you man.

That's an interesting thought and not one I've really considered about bracing. (I'm fairly new to having any 'real' understanding of acoustic guitar construction). I would IMAGINE that over-bracing is generally found in cheaper guitars or those with less experience building them? I'd imagine finding the balance of sufficient structural support vs ability of the top to 'breathe' a really difficult one.

Thanks.