# Formula for ohms in speaker chain

What is the formula to calculate how many ohms your speakers will put on a power amp?

For example two 8 ohm speakers daisey chained together

Series connection: $R_{total} = R_1 + R_2$.
Parallel connection: $R_{total} = \frac {R_1 \cdot R_2}{R_1 + R_2}$.