This app will calculate the total impedance of multiple speakers in both series and parallel connections.
If you play electric bass, guitar, set-up sound systems or install speakers in the mobile audio industry, this app will make calculating impedance easy.
For musicians, you can calculate the total impedance of speakers you intend to connect to your amplifier. Knowing the total impedance will keep you from putting too large of a load on your amp.
This app is free courtesy of Carvin.