SOUND ON SOUND

[Jadoube]

Totally slacken the truss rod, ideally removing the nut/adjuster (it also gives you the opportunity to give it a clean and get some fresh oil on the thread so it works smoother when you re-assemble).

You need a good flat surface, a couple of good clamps and a spacer 3 or 4 mm thick. Lay the guitar fretboard down on the flat surface with the spacer between the fretboard and the flat surface beside the 7th fret. Then clamp at the nut and heel, taking care to apply clamping pressure slowly. Sight from the nut towards the heel regularly as you tighten up until you see a slight forward bow. Leave it overnight to settle.

With luck, when you release the clamps the following day the forward bow will have set. If it returns to a back bow, it is worth going through the same process again but using a hairdryer to gently heat the length of the neck. Not so hot as to damage the finish, but getting enough heat into the neck so it is quite warm but not really hot. Then leave to settle over night again.

Words of warning. If you don't feel confident working like this, don't do it. A decent guitar tech should be able to do this for you. If you do go ahead, take care when clamping to avoid putting a twist in the neck.

Finally, raising the saddle might remove the buzz, but it will mess up the action increasingly beyond the 2nd fret and the guitar will intonate increasingly sharp. Solve the problem, not the symptoms.

Let me know if you have further questions.

Andy :beamup:

I have watched real guitar techs do this! I recall my one friend (Well I thought he was my friend but I was probably this annoying teenager with weird hair getting in his way ) who worked on classical guitars a lot had a heated framework that he would clamp around the neck to "straighten" them out. I think I will start with the obvious of seeing if the neck can be pulled into enough relief... if that doesn't work I have some heavier strings... aka the 'right' strings. But I am curious what folks do to make really light strings work... is it just matter of skill? I can believe that.

[zenguitar]

As far as the geometry of the neck goes, there's no difference between electrics and acoustics. Both are equally capable of taking all sorts of different string gauges, from very light to very heavy. And where there is a truss rod, both can handle switching from light to heavy or vice versa. Where there are problems, it often comes down to how the wood of the neck handles those changes of tension and associated truss-rod adjustments, coupled with fluctuations in temp. and humidity over the years.

Making light gauge strings work with acoustics is more to do with the body than the neck. An acoustic guitar body has to be built light enough to vibrate and resonate freely, but structurally strong enough to handle the forces generated by string tension and playing.

At the risk of a slight over simplification, the gauge of strings used sets bounds on the amount of energy that is put into the system. Acoustic guitars are typically built to use medium gauge strings, 11's or 12's. If you put on heavier gauge strings you put more energy into the system with the risk of overdriving the top. If you put on lighter gauge strings you risk putting in insufficient energy to get the top working properly.

Then you factor in your playing style. Heavy strumming puts in a lot more energy than light finger picking. Or to look at it in another way; heavy strumming is equivalent to going up a gauge (or two), light finger picking is the equivalent of going down a gauge.

The mistake people often make is conflating light gauge strings with 'easier to play'. That is untrue. Lighter strings have lower tension, but that can often require a higher action than can be achieved with heavier gauge strings.

For example, in the early 90's I lent the acoustic I built to a friend for a recording session because he couldn't get a good result with his acoustic. His guitar had 10's on it, and he was convinced that mine had 9's because it was so much easier to play. I had to put both guitars side by side and prove with a calliper that my guitar really did have 13's on it.

Andy :beamup:

[Wonks]

As an aside... does anyone string their acoustics with extra light strings?
I recall some session guys used to do a thing called Nashville tuning where they would string E B G with normal stings and then D A E with the light strings from a 12 string set. I never thought about what that would do to the neck...

It's all about tension, not the string gauge. The 3 light bottom strings are tuned up an octave from normal, and the overall string tension is pretty much kept the same, certainly within the scope of a small truss rod adjustment if necessary.

You'd probably get a bigger overall tension change by going up or down a gauge, say from 12s to 11s, than by going to Nashville tuning. It's all about selecting the right thickness for each string to keep them all relatively balanced.

In a typical string set you'll get variations in string tension, with the B string almost always having the lowest tension. There have been string sets that have been selected for equal tension, and I know I've used one set long ago, but they never really took off.

Double-action truss rods are probably being fitted these days to a lot of guitars because it allows the manufacturers to get away with lower-quality construction standards and lower quality/less well seasoned wood. An un-tensioned neck should really have no reason not to be perfectly flat, but certainly with reference to cheap Chinese kit guitars, I've seen many that start out with back-bow which string tension alone can't cure. Whilst they do offer more adjustment and are a good idea, they do also allow for lower construction quality.

But wood is a natural product with variations in density and strength, so even high-quality makes occasionally have necks that go a bit wayward, especially as they age. So I'm all for double-action truss rods as it does allow easy correction of back bow that would otherwise require an expensive trip to the luthier for heat flattening treatment.

[Sam Spoons]

As an aside... does anyone string their acoustics with extra light strings?
I recall some session guys used to do a thing called Nashville tuning where they would string E B G with normal stings and then D A E with the light strings from a 12 string set. I never thought about what that would do to the neck...

You could go for 11's and see if they are a workable compromise.

FWIW I use different gauges on my acoustics, my 25.5 scale D45 alike has 13-56 (but is tuned down a semitone, otherwise it would have 12-54) the Brian Eastwood (24 ¾") has 11's or 12's depending on my mood, the Emerald (24") has 12's. The only one strung with extra light strings is my Aylward Selmac but that is unusual as it has a 26.5" scale and 10-46 Gypsy Jazz strings.

Years ago I used to use 10's with a plain third on the Eastwood but the third just stuck out too much and when I went over to sound hole pickups I had to go back to a wound third anyway. The light strings didn't;t cause any neck issues on it though.

[Dynamic Mike]

See Andy's post re what an experienced Luthier would do... :D

Following Andy's advice I fixed the same problem on my Telecaster. It was a good few months ago & so far it's stayed fixed.

[Murray B]

RE playing with 10's versus 12's

I used to use very light acoustic strings on a cheap acoustic I had - it worked ok but never really sounded great. A heavier gauge does put a bit more energy into the guitar - kind of brings them to life, So long as you aren't hoping to do lots of string bending then 12's might work for you, 11's as a halfway or 10's cause you really like them - it's a personal thing. I wouldn't personally use 13's ever again as they hurt too much and I was concerned that they would pull the guitar apart.

I've played with electric players who use 8's and I can't get on with strings that thin. But then again I can't bend a whole chord up a tone like they could...tried and failed with the 10's on my Strat - I cheated and used the term.

I use 12's all the time acoustics these days but the calluses I've developed on my fingers are thick enough for me to not always require oven gloves :roll:

[Jadoube]

As far as the geometry of the neck goes, there's no difference between electrics and acoustics. Both are equally capable of taking all sorts of different string gauges, from very light to very heavy. And where there is a truss rod, both can handle switching from light to heavy or vice versa. Where there are problems, it often comes down to how the wood of the neck handles those changes of tension and associated truss-rod adjustments, coupled with fluctuations in temp. and humidity over the years.

Thanks Zenguitar. I've noticed you are one of the main smart people on this forum. This guitar has some 'bow back'; that is, with strings off the neck goes back more or less at the 12th freet/body join. Not flat end to end. I don't really have a place in my apartment where my wife would let me clamp a guitar neck to the furniture so I'll try to finesse it into some kind of playable shape.

Making light gauge strings work with acoustics is more to do with the body than the neck. An acoustic guitar body has to be built light enough to vibrate and resonate freely, but structurally strong enough to handle the forces generated by string tension and playing.

At the risk of a slight over simplification, the gauge of strings used sets bounds on the amount of energy that is put into the system. Acoustic guitars are typically built to use medium gauge strings, 11's or 12's. If you put on heavier gauge strings you put more energy into the system with the risk of overdriving the top. If you put on lighter gauge strings you risk putting in insufficient energy to get the top working properly.

Then you factor in your playing style. Heavy strumming puts in a lot more energy than light finger picking. Or to look at it in another way; heavy strumming is equivalent to going up a gauge (or two), light finger picking is the equivalent of going down a gauge.

The mistake people often make is conflating light gauge strings with 'easier to play'. That is untrue. Lighter strings have lower tension, but that can often require a higher action than can be achieved with heavier gauge strings.

For example, in the early 90's I lent the acoustic I built to a friend for a recording session because he couldn't get a good result with his acoustic. His guitar had 10's on it, and he was convinced that mine had 9's because it was so much easier to play. I had to put both guitars side by side and prove with a calliper that my guitar really did have 13's on it.

Andy :beamup:

HA HA. Yes... my actual skills and experience in the music business are in the studio. I am now a 'retired' (has a day job) producer/engineer and I have a great appreciation for studio stories because I know how emotional recording can get... in spite of all logic and rationality.
I like these skinny bendy extra light little strings because I don't play acoustic very often and when I do I am a hack at best. I like how easy this guitar plays... I can noodle to my heart's content without purgatory for my fingers. It feels like a secret indulgence and it's on a dirt-cheap guitar so no guilt about damaging anything. I have got a nice Taylor and it sounds great but, I don't play it enough. If I can get this Yamaha working I may get a lighter gauge on the Taylor as well.

What I am learning is that I can use these light strings but I have to ensure the guitar neck is correct first. In fact, my original proposition that "...extra light acoustic strings too light for the neck relief?" appears to be wrong. Good to know!

[zenguitar]

As far as the geometry of the neck goes, there's no difference between electrics and acoustics. Both are equally capable of taking all sorts of different string gauges, from very light to very heavy. And where there is a truss rod, both can handle switching from light to heavy or vice versa. Where there are problems, it often comes down to how the wood of the neck handles those changes of tension and associated truss-rod adjustments, coupled with fluctuations in temp. and humidity over the years.

Thanks Zenguitar. I've noticed you are one of the main smart people on this forum. This guitar has some 'bow back'; that is, with strings off the neck goes back more or less at the 12th freet/body join. Not flat end to end. I don't really have a place in my apartment where my wife would let me clamp a guitar neck to the furniture so I'll try to finesse it into some kind of playable shape.

Thank you for the kind words. :thumbup:

What you have spotted at the neck/body join is a hump, but not back bow. A back bow is in the free length of the neck, and one of the most likely causes of your buzzing. The hump where the neck joins the body is something different, but very common on mass produced acoustic guitars.

The neck joins the body at a very slight angle; it can vary a little but is usually about a degree. Where the fretboard continues over the body it is glued direct to the soundboard. In an ideal world there would be a very thin wedge of wood between the fretboard and the soundboard so that the fretboard continues in a straight line. But usually it is just glued direct. Of course, the expectation is that the fretboard will pull the soundboard up a little but there is usually a substantial brace on the back of the soundboard between the sound hole and the heel block.

However, by the time you get to the dusty frets above the neck/body joint intonation is largely wishful thinking anyway. So it's not really a problem. And it certainly wouldn't be the direct cause of buzz around the 2nd fret.

Next time you are in a shop full of acoustics sight down as many necks as possible. Award yourself £1/$1/€1 for every guitar you spot with the fretboard hump. You should be able to take yourself and the lady wife out for a drink or two.

:bouncy:

Andy :beamup: