Depends how much I'm playing the guitar. I've changed the strings on my 25th once every two weeks. If its been over a week and I have a gig I change them the night before. My Silo Spec cause I play it a little less. Once every three weeks. I had a huge single coil blues mood a couple months back and I hanged strings once a week. Not so much anymore.
All guitars go back into their cases after use. No reason not to and to risk possible damage.
My JP barely leaves the case, and I'm yet to change the strings on it since I purchased it 8 months ago. Sad really, I'm too cautious with it so I don't play it much...
Like Jamie, I use my ears : if the strings start to sound dull, I change them.
Besides, before each show, I change my strings ... just to be on the safe side !
My guitars are all sleeping in their case or gig bag.
Depends - I gig regularly and take two guitars with me. In the summer months when it is hot and humid I get one gig out of a set on the main guitar I play that night. The rest of the year I can usually get two gigs.
I also keep my guitars in their case - I find that just leaving them sitting out causes the strings to dull and prematurely wear...
Trust your ears, they'll tell you when to change. Aside from the dullness they won't hold stay in tune quite as well as they did when new.
When I wasn't gigging (many years ago now) my rule of thumb was 28 hours, which was about a month of noodling at home. Of course, when I started rehearsals and gigging, that number changed drastically. One hot sweaty gig or a few rehearsals and I'd have to change them. But that was normal strings. Coated Slinkys last longer.
Yesterday I was in the recording studio for six hours with a new set of coateds and they are still quite bright and zingy today, which is impressive. My last set of coated slinkys got through a ridiculously hot and sweaty gig with significant discoloration but still sounding very good when normal strings would have been totally dead. In fact I kept them on the guitar for another couple of days and did another rehearsal with them before changing. (Edit: I don't worry about discolouration, I don't think is necessarily correlates to string life or tone, particularly with the coated strings).
At home my guitar is on a stand where she is easy to reach. I play my guitar more often when it's out and grabbable, and that helps me not suck quite as much.
I usually change them 1 to 2 times per month. But again it also depends on how they sound, feel and stay in tune. I do use the EB string cleaners couple of times a weak to take off any excess grime that may build up. Definitely helps keep them last longer. I only play at home at the moment, so if I gigged I'm sure that would change a lot.
Oh, and the guitars stay in their cases at all times if I'm not playing. I also alternate my guitars so that's probably why I dont change the strings as often also.
I change my strings about every two weeks (depending on how frequently I play; if its every day at the end of two weeks they need it!). As for keeping guitars in the case, I have three out at all times (since I like to switch guitars to play different stuff in the middle of practicing), but the remainder stay in their case. I have a really hard time putting away my Y2D since it just looks so amazing that I want to play it!
After every gig I change them. If no gigs for a month...every two weeks. Yes, I keep them in the case at all costs. Some of the peeps around here saw what happened to one of my JP's when I left it out.
After 24 hours (e.g. 12 two hour practice sessions) I change the strings. I would change them more often but I really can't afford too....
My Silos always go back in the case after use.
Whenever I feel I don't get the right response/crispness I change the strings, so about once a month for me. Never keep them in the case, I have a nice stand where they can all be together as a happy family.
I change strings often, new sound better but with my new found love for cobalt strings may not change as often! As far as case I generally have two on stands in my inner sanctum and then rotate the others in and out. If out cased ,cleaned and put in the vault(i.e. the fing closet)
After every gig I change them. If no gigs for a month...every two weeks. Yes, I keep them in the case at all costs. Some of the peeps around here saw what happened to one of my JP's when I left it out.
On rare occasions I have actually killed a new set in a day lol. Normal string change for me is about a month if I am playing steady. But I am very meticulous when it comes to wiping down my strings after playing, by far the best little secret is a device called the Tone Gear String Cleaner, which is a padded device that opens and clamps on all 6 strings that you slide up and down the neck so you get the bottom as well as the top equally- Tone Gear Guitar String Cleaner | Sweetwater.com
You can use nothing or pour a little of your favorite cleaning solution on the pads and it will keep them feeling new for quite sometime. One thing I can't stand is dirt or sticky strings where you cannot slide up or down with ease on.
As far as cases go I have three guitars that rarely ever go in their cases, which are my main players. But I would advise to put it away or at least in a gig bag if you are worried about dinging the finish.