Do you want to hear your bass at its most natural? Does your amp have an effects loop?
Well instead of plugging your bass into the normal input jack, plug directly into the effects loop return. This (typically) bypasses the pre-amp stage of your amplifier and connects you directly to the power amplifier! You lose all the gain and EQ control that the pre-amp gives you, but instead get to hear your bass in its most natural state!
Is it useful? Maybe. Depending on what you your bass to sound like. But it’s definitely interesting!