The Earthquake PUMP-12 - A Unique Passive Radiator Module. They can be integrated into virtually any sub/ cabinet combination. The Graph shows the green area is 30% less than the yellow area. With less current draw, the speaker’s impedance increases and therefore, SPL also increases.In summary, the PUMP-12 increases the subwoofer’s SPL by 6dB without the need to draw more amplifier current.
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