I am getting a new concert ukulele and I was wondering whether the tuning is different for a concert?
is it still GCEA? or is there a better sounding tuning than soprano standard?
The short answer is no, the tunings are not different. The soprano and concert are usually tuned the same way: GCEA. The baritone uke is the only size that is normally tuned differently.
As far as "better sounding" goes, that's a matter of personal preference. One option you might try is to use a low G string; tune the G as a low G instead of the normal re-entrant high G.
There are two tunings for the soprano: one, most commonly used in the west, is GCEA This tuning is also standard for concert size. The second tuning for soprano is my favourite and not so common in the modern era: ADF#B (All Dogs Fear sharp Bites! - yes, I made that one up...). This tuning is not for use with a concert size.
From a soloists point of view, the two differing timbres are much like sunset GCEA and sunrise ADF#B, or, if you like, the difference between a solid spruce timber (bright, happy) and a solid ceder timber (sombre, dark).
Size of a stringed instrument is relative to the pitching you may use and affects life of the string, thus it is important to purchase specific concert or soprano strings as there is no use-all string.
You'll find that that second tuning (ADF#B) soprano tuning to be sweeter for laminates as well as solid timbered ukes, even better where the uke has bone nut and bone saddle.
If you go with the second tuning, which is slightly higher in pitch, it will tend to make the strings overtune when you tune back down. For example, if you're going to work in an ensemble where both concert and soprano are tuned to GCEA you'll need to either transpose or tune down to that pitch and as the strings have been tensioned to the higher pitch/tuning of ADF#B, they'll have this tendency to "re-tune themselves" upwards so it'll take a couple of goes before they settle back down.
When you first string your uke or you've just bought a new one you'll find that constantly overtuning the uke by half a tone will hasten the holding of tuning, stopping that constant detuning that's prevalent with new strings.
It's important to use good quality strings. Uke strings are not the same as nylon classical strings. Well, maybe, in an emergency, although most definitely not recommended! Use strings specific to concert size or specific to soprano.
One simple rule may assist you to avoid string breakage: when tuning up to a note, when unsure where you are in the octave, tune back down to the same note. The pitch will be obvious that you have tuned down too far which is better than missing or overshooting the correct octave and causing the string to break...ping!