It can be, but it's not the recommended way to run it. Unlike EMG's standard preamp design, the Blackouts preamp didn't rely on 18 volts for increased headroom. It had more headroom at 9v. So usually when people ran Blackouts at 18v many of them didn't feel it was an improvement. In other words, 18v on Blackouts or Blackouts Modular preamps does not provide the payoff that it does on EMG's.