My ears rang from 15 watts even though I largely obstructed the combo cab with makeshift gobos. You can use gobos as a final volume control. Most guitarists only think of putting the amp in the middle of the room. But when you block the cab, this opens up possibilities. Gobos are interesting and I will look into them more. You can interlock some models to form an instant cabinet isolation box with sound-moderating openings to fine-tune the SPL.
Clear gobos more
StackIt interlocking gobos
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