Some condenser microphones require 48 volts to operate, also known as "phantom power."  what do you do if your mixer or amp doesn't have "phantom power"?  Buy a ART Phantom1, that's what you do!

Specs;
• Input Connectors: XLR female
• Output Connectors: XLR male
• Frequency Response: 10Hz - 25kHz
• Output Phantom Power: 48V DC +/- 2V
• Output Noise: -115 dBV
• Current Drain: 14mA
• Power: 18V DC (Adapter included)
• Dimensions: 5.25x2.75x1.75 inches (130mm x 74mm x 45mm)
• Weight: 1.3 lbs (315g)