If you connect them to an impedance matching speaker selector most receivers and amps will work fine. https://www.amazon.com/SS4-Speaker-Selector-Impedance-Matching/dp/B002I9XKTE
The impedance button will add resistance to keep the amp happy. The switcher should be rated to handle at least the amount of power that the amp produces
You could also use impedance matching volume controls that could be located remotely which could be very convenient. These have adjustments to set them to provide the correct amount of impedance matching.
If you didn't use one you would need an amp stable to 1.5 ohms (no receivers will do that) and expensive or a 6 channel amp.