I'm posting this article on my website to help further educate guitarists on the topic of truss rods. Quite often guitar necks shift from too much bow to too little. Far too often it is blamed on the last person that adjusted the guitar's truss rod. I'm not suggesting it was or wasn't- but this actually happens mainly from a change in the relative humidity of the climate the instrument's exposed to. This kind of change can happen within as short as a day. What this means is, if you pickup your guitar from a tech, where it plays beautifully - and then a month ( or day or week) later it plays awful - it's a good indication that something on the guitar has shifted. It does not necessary mean the tech did a bad job, or he/she ruined your guitar. I have always offered complimentary truss rod adjustments - It takes no time at all.
The truss rod is a simple device that basically has one purpose: to counter the pull of the strings. That's it. It isn't meant to adjust the height of your strings; you can't set your intonation with it; and with a little foresight, you aren't going to render your guitar useless by attempting to adjust it.
When you bring your guitar into J.Haven for a setup, your truss rod is adjusted after your new strings have been strung up to pitch. Some necks require a “settling in” period after adjustment and are left as long as required to settle.
Every guitar is different but typically your truss rod will need adjustment when changing tuning or string gauge, or have seasonal changes ie. Winter to spring, summer to fall, etc. Any time your guitar gets buzzy after it's been properly setup (for a certain tuning and string gauge) it is likely due to the neck needing a re-adjustment. Just bring it by the shop or attempt it yourself using the guide. Chances are a quarter turn one way or the other will correct the problem. Considering that Alberta has a very erratic climate, it is likely your truss rod may need more routine adjustments than in other localities.
Let me guess, it was playing just fine before winter and you just picked it up to discover none of the notes play anymore. Anywhere. The strings are frapping out all over the place. Nothing but buzz. What happened? Did someone sit on this thing or something? Does it need a setup?
I can't tell you how many of these I see every winter, it's really astonishing! If you guitar sounds like the description above, it's probably completely dried out! As most acoustic guitars dry out, a hump rises where the neck joins the body and the top of the guitar sinks in. As the top sinks in, it pulls down the strings with it, which is why the action drops sometimes so low that the strings are ON the fretboard. Sometimes you catch it early, and you just find the buzz at the 14th fret area.
What to do about it: Get an in-case humidifier and check it weekly! I use 2 on every guitar I have and that seems to work relatively well for me. There's an article I wrote a while back http://www.jhaven.ca/2/category/humidity/1.html as well an excellent article from Taylor Guitars here http://www.taylorguitars.com/global/pdfs/greatest_hits.pdf.
If things are really bad, I'd go to the grocery store and buy some sponges and ziplock bags. Grab a couple bags, punch holes all over the bag and stick a moist sponge in each (make sure to squeeze them out so they're not dripping) and put one in the soundhole, the other at the neck joint or up by the headstock, and close the case. Each week, get the sponges wet again. You'll begin seeing an improvement anywhere on average from 2-4 weeks.
Guitars are commonly manufactured in climate controlled plants, usually somewhere around 47%-54% relative humidity. This is where your guitar likes to be. This is where it was made to be and live out its life. If you change that, you can kill it! Alberta Winters are VERY dry.
This article is obviously more centered on acoustic guitars, but even electrics show signs of stress due to low humidity. Electric guitars being mostly finished are therefore ‘mostly’ protected from environmental conditions like humidity. Where they get it bad is in the fretboard & the neck, where as an acoustic guitar takes it is everywhere.
What is relative Humidity?
It is basically the amount of humidity in the air.
What is Alberta’s relative humidity?
It’s always fluctuating but you can count on it being nowhere near 45%. In the house it’s often much worse, because of heating/cooling systems, the forced air is even dryer than outside in many cases. Even where there is a built in humidifier, your house climate control is probably putting your guitar through the ringer.
What happens to the wood of your guitar?
Wood expands and contracts, twists, shifts, and contorts long long after it has been cut and dried for use. Wood being a once living fiber is as unique in its structure as any creation of nature, therefore each guitar will behave differently, even when coming from the same manufacturer (and each manufacturer treats their wood differently). You ever play a guitar that just feels alive? It’s because it has soul! It’s how the wood is handled from day one. Anyways enough of that…
Common symptoms of a dry guitar:
“Oh no, my guitar has some of these symptoms! Is it a lost cause?”
Not at all! Depending on severity and how long it’s been dry, often a guitar can be brought back to its original condition by simply humidifying it properly. Other times, it is a combination of humidifying and readjustments. Extreme cases are specific to the individual guitar and best to have it looked at by a pro.
How can I prevent it?
Use a humidifier if you own an acoustic guitar! Some guitars are hardier than others so if your guitar is worth anything to you, go buy a $12 humidifier from your local guitar store and keep it in the case with your guitar. Easy. On expensive guitars, in the winter, I’d pass along the suggestion on Taylor Guitar’s website and use 2 humidifiers of the damp-it variety (the Planet Waves work well too). Place one in the sound hole, one near the headstock, and keep the guitar in its case when not in use.
Electrics with sharp fret ends? Get them filed off. High frets? Get them popped back in to place (and glued). Any competent repair person can do this. Having your fret ends filed will give you back the smooth feel of the neck as it had when it was new, or should have had when it was new. It’s common for new guitars to be a little distressed, as there is a settling period after manufacture that can continue on after once you’ve taken it home.
What about guitars that have been neglected for years and are all bent out of shape or cracked up? Can it be fixed? Quite likely although each case is different and it’s best to take it to your guitar technician for a thorough evaluation.