A couple days ago a young man called me from Dennis, MA - about an hour drive away, at least, on Fourth of July weekend - and wanted to buy some new strings. I was somewhat amazed that he was willing to drive here on a Saturday evening to buy them but it reminded me of how important a new set of strings can be.
There was a time not too many years ago when there were maybe a half dozen choices in steel strings for acoustic guitar, and perhaps that many for electric. Even fewer for classical (nylon stirng) guitar. Today there must be at least three dozen major manufacturers of strings offering many, many options in various metal alloys, gauges (string diameter), tensions, coatings, etc. It can be confusing to say the least.
But for most acoustic guitarists the choice begins with materials, which for the most part can be reduced to either phosphor bronze or 80/20 bronze. I don't know the actual alloy compositions of each, but the 80/20s have more brass. All-steel strings work well on electric guitar but sound much to harsh and "tinny" on an acoustic. It's best to look first at the actual strings and define what we're talking about under the banner of "steel strings."
All so-called steel strings have a solid steel core. Except for the top two strings (B & high E, which are in essence cores themselves) those cores are wrapped with the above mentioned materials, those wrappings being thicker to give a lower sound on the lower strings and gradually decreasing in overall diameter on the strings that will be tuned higher. The outer wrapping lends little to the overall strength and durability of the string; that comes from the core. This is were the manufacturer tweaks the tensile strength to give the string qualities like a firm or soft "feel," which in turn translates to variables in tone and volume. However, the wrappings do certainly lend subtle but important and noticeable varieties to the overall sound of the string.
It is generally accepted that the 80/20 strings sound brighter than the phosphor bronze. If you are looking to improve the high end of your guitar these should probably be your choice. I happen to prefer phosphor bronze because I think their sound is more "even," for lack of better description.
The other big, big issue is the guitar on which the strings will be used. On my Taylor 810 and all the larger bodied Martins I've owned those phosphor bronze strings bring out the punch and resonance in the low end, something that I love. Smaller bodied guitars will exhibit less variation between the two st
I'm still on the fence about the new generation of coated strings that feature a micro plastic coating that is supposed to radically increased the life (i.e., new string sound) of strings. I know that many, many thousands of guitarists love them - and they are standard on new Taylors - but I am not a fan of the Elixer brand coated strings. To my ear they are just too brash and bright. The Martin/Cleartone SP series however sound quite good. Other coated strings are showing up all the time and while they cost almost twice as much as non-coated strings they may be worth a try, especially if you have the misfortune to have very sweaty hands that kill new strings quickly.
Next: String gauges - the biggest conundrum of all!
Peace & good music,