4 Marshall stacks is a nice place to start. You
will get an awful lot of bang for an awful lot of
bucks.

Seriously though, more info is needed. The short
answer is buy as many watts and as many speakers
as you can afford. There are some great deals to
be had online at places like craigslist and ebay.
Hartke makes some great amp heads for a reasonable
price, as does Acoustic and Gallien Krueger. Go to
musiciansfriend.com and zzounds.com, both good
places to start. Also guitarcity.com lists a ton
of bass gear new and used. See if there is a
music-go-round close to where you live and go
there.

Hope this helps.

200 watts thru a 2x10 or 1x15 is a minimum to get
the job started, but more is better and may be
needed. A lot depends on the size of the room, PA
support how loud/big the drummer and gtr player are.

I am playing thru a 500 watt d class head (GK
MB500)and match that to whatever cabs are needed for
a particular situation.

I recently purchased a 350 Watt Fender Rumble for $500 to use as a practice amp... Often, however, I find myself using it at smaller gigs. It kicks ass! Fender also makes the Rumble in smaller wattage for less money. If I were you I would get the $350 if you want to spend the money as it has plenty of power... However you could probably get 1 model down save some bucks and still have plenty of headroom.

By the way this has a great XLR out on it as well....

--Tony

If you're looking for "bang for your buck" check out Carvin amps, incredible quality & very competitive prices (I have one of their basses & we use a Carvin power amp for our PA). Another brand that is undervalued & great quality is Yorkville / Traynor you can find some great deals on used Yorkville amps (their vintage tube stuff is getting pretty pricey - I should have kept the one I owned back in the '70s LOL)

In terms of wattage it depends on what your needs are. Personally I like the idea of go big or go home (I run an 800w Yorkville head through Eden 2 x 10 and 2 x 12 cabs) but that's just me.

Hey Sal,

I don't know if this is still valid, but I always found that Peavey gave the most bang for the buck. So check out their website.
I started with Peavey and played different amps like Ashdown...now I am very happy with Markbass (healthy for my bold back, light to haul around and big sound!)

Sean ;)

everyone knows what i'll say !!! lol

Maybe too late, have you bought your amp. If not, I can offer this. I recently wanted to upgrade from a practice amp, and went to a well known local store. They had recently been bought out by a national chain and were clearing out all the stock that independent had but not sold by the chain store. I was able to get a brand new Hartke LH1000 and a Hydrive 15" cab for $500. That's less then either the head or cab list for. I realize that this is a weird scenario, but deals for good gear can be had. Good luck.