Eris E3.5BT or Eris E4.5BT speakers incorporate professional-caliber power amplifiers to produce clear, full bass and high-quality sound. Power amps of this sort require more power than portable batteries can deliver, so the Eris E3.5BT or Eris E4.5BT speakers use AC power.
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Please contact PreSonus Technical Support by creating a Support Ticket at My.PreSonus.com for further assistance.
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