Ok. So how have bands been doing it for the past 40 years? Like in the 60's when 100watts was a lot of power and they could still sound good? Or in the 80's when 300watts was a lot and they could sound good? Or today when bands use in-ears and no amps onstage or just monitors? Players have been getting punch and feel for years and on a lot less wattage than your talking about.
Watch out for the Koolaid!
As one who was around back then, things are very different, and IMO, much better these days. Today, there are drivers available that cabinet makers couldn't even dream of back them. However, there is no 'free lunch'. Some of today's cabs that are small, loud, and go deep, pay a cost in efficiency (i.e., volume per watt). It takes more wattage to get these more fullrange cabs up to full gig volume. The good news today is that watts are light and relatively cheap.
Will everyone need 600, or 750 or 1000 watts today. Of course, not. However, it is great to know you can drive huge low end and a very even, clean response at high volumes out of cabs that are a fraction of the size and weight of what you would have needed way back in the day. That, to me is a wonderful trade-off.... buy an amp with 500-1000 watts that weighs between 5 and 15 pounds, and then use the cabinet of you choice.
It is a wonderful time to be a gigging bassist regarding gear choices. I can literally do a moderate volume rock/pop/funk gig now with 500 watts driving a 3012LF loaded 2 or 3 way cab, and the entire rig weighs under 40 pounds!
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