How much volts are from amplifier?

[zstoja]

Amplifier is 150W per channel and 8 ohms. How much volts are in speaker cables?

I need it to buy right switch for speakers.

Thank you.

[Kursun]

The Power Formula: W=V*I
The Ohm's Law : V=I*R
From the above formulas V=SquareRoot(W*R)

For 100W output at 8 Ohms: V=28.3 Volts
For 150W output at 8 Ohms: V=34.6 Volts
For 200W output at 8 Ohms: V=40.0 Volts

For 100W output at 4 Ohms: V=20.0 Volts
For 150W output at 4 Ohms: V=24.5 Volts

Note: Though the output voltage is lower for 4 Ohm loads, the current is about SQRT(2)=1.41 times more compared to 8 Ohm loads, for any given power level.

I would buy a switch rated for not less than 100 V.

[zstoja]

Thank you very much!