mr dave

First things first, congrats on getting in a band, just remember the golden rule - ALWAYS HAVE FUN. If you're not having fun in the band it's going to destroy your soul.

As for live performances most venues have a PA system in place so bands don't have to really rely on their amplifiers for more than tone. It just looks a little funny when you mic what looks like a practice amp.

Something else to keep in mind a low end instrument + good amp will ALWAYS sound better than a good instrument + crappy amp.

Also with your current budget I'd suggest waiting and saving up a bit more, especially if you're hoping for a long term solution (shoot for closer to $800-$1000). Worse case, just put your current amp on a bar stool when you practice with the band - by raising it closer to ear level it will feel louder in the room.

As for the wattage question that's not quite how it works, there are a few other factors and variables to consider, mainly the amperage and impedance (there's also circuitry and Class A / Class B but that's a whole other can of worms and a HUGE jump in price). I don't quite remember exactly how they all tie together but it's like the difference between using a single dump truck to carry a load vs. using a fleet of compact cars to carry the same amount. One end result is the same but the delivery and impact are not.

The sound quality for a low-B string is not going to be affected by the wattage or overall power of the amp, but definitely by the scope and range of the speaker and built-in EQ. The only real way to know is to test it out in person. Myself I settled on an older Warwick bass amp (the original Sweet 15 150W combo) which has an LED that lights up if the sound starts clipping which makes it super easy to tweak the EQ to maintain a clear tone.

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