My guitar is strung with what I think is light gauge strings (it was already strung when I bought it from the shop). I understand that the lighter the string, the easier it is to press down on the frets (I could be wrong?)
However, is that the only effect the gauging has? Do different gauged strings produce differing sounds? What difference is there in sound? A softer tone, or a harder one?
Thanks.
Lighter strings are easier to bend. I guess they’re easier to press down too, but I think the action of the guitar (the height the strings are raised away from the neck) would make a bigger difference than the string gauge.
It does indeed change the sound. I’d be hard-pressed to describe it, but I guess you’d say thicker strings give you a fuller sound. Have you heard Stevie Ray Vaughan? Nobody used thicker strings than him. Maybe that’d give you an idea.
Lighter strings make it easier to fret notes, and easier to bend notes. They also bite more sharply into a novice’s fingertips. Fatter strings have more substance, so they have more ability to sustain a note. They also have a “fatter” tone. B.B. King, for example uses heavy strings. Billy Gibbons of Z.Z. Top reportedly uses fat strings for tone’s sake. Fatter strings tend to stay in tune better than the little ones.
It’s a judgement call.
Ditto on fretting & bending. Fatter tone, if you don’t have the intuition for that term, means that the harmonics have more amplitude and sustain.
A heavier string must be under higher tension to produce the same note as a lighter string of the same length. That’s why it’s easier to play lighter strings–less tension.
A heavier string under higher tension also produces richer harmonics. Whenever you pluck a string, it vibrates at its fundamental frequency (a guitar’s A string vibrates at 110 Hertz (times per second)). But it also has overtones that vibrate at multiples of that–220, 330, 440, etc. The volume of each of these overtones depends on many factors, the string is just one. The heavier string under higher tension tends to have a richer set of overtones that sustain longer. They also take a little more effort to pick and give a more pronounced attack, the click when you first strike the string.
To make a sweeping generalization (which has lots of exceptions), rock players like light strings (lots of them use a high E-string of .008 or maybe .009) to allow them to skim over the strings faster, and the tone of the string itself is less of an issue when you’re using a lot of special effects. Blues players tend to like heavier strings for that aggressive attack and richer tone; speed is usually not a goal for them, and they use little special effects besides an overdriven amp. (I use a high E string of .010 on two guitars I use for blues, which is very common; many go to .011; I think Stevie Ray was using telephone cables 
). Jazz players like the heaviest strings of all (I play 13’s on my archtop) for the rich tone and percussive attack.
Actually, some sources claim that B.B. King uses somewhat lighter guage strings than a lot of his contemporaries. If this string set sold as “endorsed” by him is the guages he actually uses, as claimed, this is true:
http://www.gibson.com/products/strings/strings/signature/king.html
.010 through .054 - the bottom end is rather heavy, but the top end is in the “light” range, though not the .009 / .008 “ultra lights” used by a lot of rockers.
Note that when you go to acoustic, a “light” set usually has a .012 E string, which would be “heavy” on an electric.
For acoustic guitars:
Lighter strings = easier to fret cleanly, less tension applied to the neck, less volume, greater tendency to buzz (particularly when played with vigor).
Heavier strings = harder to fret cleanly (which can also cause buzzing), more tension applied to the neck, more volume, less general tendency to buzz.
Guitars are designed for a certain string gauge. Using a lighter gauge than intended will not harm anything, but reduces volume and may give a muted tone, and will likely cause buzzing. Using a heavier gauge than intended can pull the neck into the body and damage the instrument. Some guitars are fairly robust and tolerant of heavier strings, but others will definitely suffer from the increased tension.
In addition, guitars are adjustable (nut height, neck curvature, bridge height) and these adjustments are partly dependent on the particular gauge of strings being used. In other words, if the guitar was set up for medium gauge strings, changing to light or heavy gauge will adversely affect the playability and/or tendency to buzz. It’s not unusual for even a brand new guitar to need a set-up to compensate for settling during shipping and/or a particular player’s style and ability.
Suggestions:
Try to find out what gauge strings the factory expects the guitar to have (if it’s a new guitar, this may be in the literature that should have come with it). Before deviating from this, get competent advice from a luthier and/or people knowledgeable about the specific brand and model of guitar.
If you have any concerns about playability or buzzing, get with a luthier and see if some changes in the set-up are called for.
For a wealth of general info (inluding a little about strings) spend some time poking around www.frets.com .
An aspect of tonal difference I wasn’t aware of (from frets.com). This responds to a question about a Taylor guitar.
All of the “14” or Grand Auditorium models come with light gauge strings. Its an issue of tone more than strength. So, simply put, you could safely string your guitar with mediums. Adjustments may become necessary and you may see more pulling of the top, but it will survive the tension.
You may find the sound more robust, or possibly even louder, but in trade, it may sound more pinched due to the extra tension on the top. The lights allow the guitar’s top to vibrate more freely.
How do you work out what gauge of string your acoustic was designed for? I got no documentation with the guitar, and it was pre strung when I purchased it. A quick search on Google doesn’t turn up anything, either.
I have an Ibanez Performance PF300NT, if it matters.
FWIW, Pete Townshend (in the old days) and Mark Knopfler also use heavy gauge strings, that gives you an idea of the kind of fullness that heavier gauge gives. OTOH, Jimmy Page’s advice for learning to solo like him was extra-light gauge… allows you to fly a lot faster once you get the hang of it.
God damn it, I like both Townshend and Page.
How do you work out what gauge of string your acoustic was designed for?
All I would know to do is ask someone who knows. Contact Ibanez Guitars, check with an Ibanez dealer, find a luthier or some other players who happen to know the details of that model. Seems to me surely the Ibanez company can give you a definitive answer.
If it has a spruce top, particularly a laminated spruce top, I’d be very surprised if it can’t handle medium gauge – but I don’t know for certain.
I like nylons on my Fender acoustic
Light brass and steel on my Strat.
Depends on what you play and how bad you break strings.
Lighter strings=lighter fret, break easier too.
Take it in with you to the local shop, they’ll gauge it for you.