I don't know if this the strap, the guitar or something else.
i mean, i can play perfectly in my SG, but when i shift the strap to play with the jackson, i just can't(have tried 2 rehearsals)..and its raised(strap) like twice the height comparing when i use it in my sg.

COuld it be how it connects to the guitar at the base? I do not have a jackson but my guitar has two differnt mount points and I had to change to the higher one when I started playing standing more.

Every guitar is going to feel different. Practice with your Jackson standing up and then you will get used to it. I'm teaching myself to stand and sit practice.

if it's a Randy Rhoads style guitar, it takes a while to get used to it

it does, but if a change it to higher to a more comfortable zone, well.... it kills my back, while riffin'


Dinky Style

Ah, I know why.. it's because the centre of balance for the body is in a different place. I've experienced this but the other way around. If I try to play an SG with a strap, stood up it feels weird to me. The picking hand is in a different place and the whole thing just feels alien.

In theory, playing the Jackson (I have one) will feel like your picking hand is further back, so your elbow is out further and your fretting arm should feel closer to you ?

We all get this when we pick up guitars which have different weight balances and shapes. It's totally normal. You just have to get used to playing it. Just try to get a strap height that allows you to articulate licks properly with your fretting hand and doesn't make your picking hand angle change

BINGO! I think been has really nailed it here. The "Center Point" is different on various types of guitars. Finding that spot, and learning to play in the "sweet spot" is often tough when switching between guitars that have different center points of balance.

I play a lot of "Super Strat" shapes, and most of them have similar balance. When I switch to my Les Paul shaped Minarik, I"m thrown off, bad. Takes me bit of playing to get used to it. It's very different than my ibanez guitars or my fretlight super strat.

Your body will get used to it, but don't try to play your hardest/most complex riffs just after switching. Until you practice doing the switch and playing the riffs. Just jumping in during practice can make you feel like you've lost control of your hands

Todd

Now that I think of it, I kinda felt a difference between the JEM and the Custom 24, meaning that yesterday, I felt things a bit awkward with the JEM. But I don't think that the balance center of these two axes is that different. It's probably the neck more likely.

There could be a few things:
1) maybe your string action is too high compare to SG?
2) Your strap is still too low
3) Shape of your guitar is making it harder to reach and something is blocking your hand
Try to play sitting down and get comfortable, than get up and put strap very high so the difference between sitting down and standing up is minimal, as you get more use to it try lowering the strap.
You are at rehearsal so it's a perfect time to try new things and get use to your gear!
I hope it helped!

Yes, the guys are right, it's the weight balance, in relation to the strap button points. Try to get another strap, and adjust it so it's always the same size, or mark your strap with two sizes for each guitar and - problem solved

how i was taught, if you hold the guitar correctly sitting down, That's between the knee's, It's in the exact same position standing up. but ya know i can't comment cos i hold it wrong on my right knee..

I'd try another strap too!!

thanks guys, i will get another a new strap and well, practice some basic stuff till i get the use of it.

Btw do you recomend any strap that doesn't kill your back :C and not very expensive ?