What guitar amp should I use in gigs?

Guess what!

Everyone saying that you need "at least" 100W is an idiot.

Yes, it's true.

Any venue that a 30W amp can't fill is going to mic you. Tube amps sound best when they are cranked all the way, and if you've got a 100W amp, you're never going to get to crank it up. Even if you try, the sound guys will make you turn down. If you don't listen to them, you probably won't be invited to play that venue again.

Also, A 100W AMP IS ONLY TWICE AS LOUD AS A 10W AMP!!!

I will repeat: A 100W AMP IS ONLY TWICE AS LOUD AS A 10W AMP!!!

It's true. It's science. Accept it.

In fact, the difference in loudness between a 50W amp and a 100W amp is barely noticeable. So don't get too concerned about wattage, it's really nothing more than a marketing gimmick that appeals to common macho thinking that more power is always better. When it comes to tube amps, more power means you probably won't get the best tone possible. All those Cream, Zeppelin, Hendrix, and Sabbath albums were recorded with little tube amps... usually less than 25W.

Be smart and buy yourself something of moderate power that you'll actually be able to crank up, otherwise you're spending a bunch of extra money on a super-powerful tube amp without ever getting to hear its full potential.

Personally, I prefer Laney amps. They have wonderful distortion (Tony Iommi of Black Sabbath has used them exclusively throughout his career), but they can also get REALLY clean... like, Fender clean.

You can't get them in the states right now though... so that sucks. See if you can track one down on craigslist or something and try to play it.

Someone already recommended the Vox AC30, which is a classic combo. Bogner has some excellent 212 combos. THD has some really awesome low wattage heads, but they are about $1k. You may want to check out Jet City Amp as well. They have an excellent 25W head designed by Michael Soldano that's only $250. It sounds AMAZING for the price, and at 25W you can crank it and enjoy that rich tube tone the guys running 100W rigs can't get (at least not without a power attenuator).

Head into your local guitar store and ask if you can crank up some of the low watt tube amps. Turn a 100W amp up to the same volume and see which one sounds better for yourself.

Well it depends. If you're using your spider for multiple effects and amp tones then you'll probably want something that can do the same. The series 3 spiders are quite nice and inexpensive, but you could just buy a POD (PODxt live or POD X3 live) and get plenty of tone for you buck. You'll have a good selection of amps and effects to choose from and it's all in a floorboard type setup. Boss also makes a modeling pedal board as well. Good luck with your search. Only one day to prepare is way short notice.

If it's for playing gigs, I would go with a half stack. If your budget's under $1000, you can get a decent 4X12 cab for less than $500, and a good amp head for around that much. Or, you could also go with a 2X12 tube combo amp, at least 40 watts. They're not that cheap, but usually less than a grand, depending on the brand.

I've played in live bands for years. Get something atleast 100 watts. Get a tube amp like a marshall jcm2000. One of the best sound heads you can get and get a marshall(brand) or Orange(brand) cab.

Well you cant go wrong with a Marshall! They're good amps to start with and there are so many of them!

I also agree with the guy above you gotta get atleast 100 watts or it won't cut through in a live show

I'd go for a Vox AC30 Custom Classic.

marshall half stack.........nuff said