Phantom Power Voltage Drop Calculator
Estimate the voltage that reaches a condenser microphone on 48V phantom power after the feed resistors and cable resistance.
Compare Your Options And Get Clear Answers
Estimate the voltage that reaches a condenser microphone on 48V phantom power after the feed resistors and cable resistance.
Phantom Power Voltage Drop Estimator
Enter your numbers below for an instant estimate.
How It Works
Key concepts behind this calculator
Mic Current
Enter the current the microphone draws from phantom power in milliamps.
Resistor Drop
Current Γ half the feed resistor value (two resistors in parallel).
Cable Drop
Add the small drop in the cable conductors.
Use As A Guide
Results are estimates based on your inputs. Check real quotes, rates and professional advice before deciding.
Phantom Power Standards
IEC 61938 phantom power types.
| Type | Supply | Feed Resistor | Max Current |
|---|---|---|---|
| P48 | 48 V | 6.8 kΞ© | 10 mA |
| P24 | 24 V | 1.2 kΞ© | 10 mA |
| P12 | 12 V | 680 Ξ© | 15 mA |
| Rule of Thumb | Most mics use 2 to 5 mA | P48 mic sees ~34 V at 4 mA | Check mic datasheet |
Phantom Power Voltage Calculator FAQ
Answers to common questions about this calculator.
A DC voltage, usually 48 V, sent down balanced microphone cables to power condenser microphones and active DI boxes.
Usually 30 to 46 V depending on current draw. Higher current draws more voltage drop across the feed resistors.
Very little for DC. Cable resistance is small compared with the 6.8 kΞ© feed resistors.
It can with faulty cables or unbalanced connections. Check the manufacturer guidance.