MartinLogan Aerius i Bias Voltage Check

Bias Voltage Check for Legacy MartinLogan Products

Warning - High Voltages are present inside of the electronics box. Refer any repairs to a qualified technician.

To remove the backboard, remove the speaker and power cables, then remove all the screws on the backboard. If needed, use a wide-tipped automotive trim removal tool and pry gently along the top edge of the backboard. You may have to go across the top edge more than once. It will eventually open from the top.


This is the inside view of the backboard. The high-voltage power supply can be measured at the white terminal block. Use a one giga-ohm resistor in series with the red probe of a digital multimeter. Set the meter to measure DC Voltage. On mu Aerius i, I measured 20VDC (2,000VDC actual) on both power supplies (left and right units).


Here are the official instructions from MartinLogan.














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