http://www.musiciansfriend.com/product/GallienKrueger-Brat-Pack-HalfStack-Bass-Amp-Package?sku=482546

also i have a few question, like: on that page it says the head is 125W and the cab is 200W, so how loud will it be.

and, on alot of amps, it says the wattage is different with different ohms, 400W with 8 ohms 300 with 4 ohms ect.. I was just wondering what are ohms and how do i know how many i have?

sorry if i sound like i know nothing, but i dont lol
It'll be 125 watts.
I'm not really a fan of amps of that size - it's kind of between practice/beginner amps and gigable amps but not really either. That said, that's incredibly cheap.

Most single cabs are 8 ohms.
thanks i guess but i still dont really understand.

i just dont understand how to know how many ohms i have because i want to know how loud the amp will be
It will be 125W. The head is 125W at 8 ohms and the cab is 8 ohms.
Ohms are a measure of electrical impedance (one day I'll count how many posts I've started with that sentence). Basically, your amp puts out 125 watts @ 8 ohms and 300 watts @ 4 ohms. That means that if you have an 8 ohm load (one 8 ohm cab) then it will deliver 125 watts to the cab. If you have a 4 ohm load (two 8 ohm cabs or one 4 ohm cab) then it will deliver 300 watts. If you have a 2 ohm load (four 8 ohm cabs, two 4 ohm cabs, one 2 ohm cab) then your head will technically deliver around 500 watts, however, it will overheat, fry and possibly destroy the universe.
I don't know what music theory is.

thank you jazz rock, i was looking for someone to explain it to me and you did.

now that thats under control, do you guys think this amp would suffice for jamming and a few gigs?
It all depends. Chances are, if you're doing any kind of rock and the guitars have distortion, you just won't be heard/felt. Minimum i'd say is about 300W with 2 guitarists. Then again, more watts does not equal lots more volume (you would have to times your wattage by 10 in order to get 2x the volume), but the more speakers you have.

The band i'm in has 1 guitarist who plays through the P.A. which is VERY loud, and our drummer is also VERY loud, and i still wish i had a bigger rig, although it is viable.
Gear:

Basses:
2008 American Standard Fender Jazz
Ibanez SRX300
Amp(s):
Ashdown MAG 300 C410T + 1x15
Effects:
SansAmp 3-Channel Bass Driver D.I.
To be honest, it should be fine, and although I'm an advocate of running big stage amps (GBE1200 hear hear?) most venues these days have a PA that will suffice for letting the crowd hear you. As for you own monitoring, you could probably chuck your bass amp up front of stage and lever it up so it's on a slant so the sound will be hitting you in the face, or sit it on a table at the back of the stage. Either way, my point is run the amp as a monitor, use the PA for making people wet themselves
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