Re: How much does increasing wattage increase volume?

Adding another cab in parallel with the existing one *might* do the
trick. It all depends on the speaker efficiencies. You'll gain a lot
more there, potentially, than simply raising the power from 180 to 300
W.

Welllll... this is another one of those situations where the numbers suggest one thing and the real world suggests another. Yes, speaker efficiency will get you more volume, but (1) It's so dependent on the cabinet design and its interaction with the driver that the resulting response will be a pig in a poke, and (2) more-efficient cabs invariably have less low-end response, it's a zero-sum trade-off. Bass cabs are a whole 'nuther world than guitar cabs.
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