I-S
Good Evening.... Infidel
No. If the impedance of both drive units is equal (which it should be at 8 ohms), then by the equation for power, (V x V) / R, then the power is dependant on the voltage that the amplifier can generate across its terminals. A 120W amplifier can generate 1.414 times larger voltage across its terminals than a 60W amplifier can.
Now, the only issue with this is that the impedance seen at various frequencies is not constant, and will have dips and peaks. For the amplifier to cope with this it needs to have enough ability to supply the current demanded for any impedance seen when a voltage within the limits of the amplifier is required. Biamping helps give this additional current ability, and since impedance dips are most often seen in the bass region, it is best to have the more powerful amplifier drive the bass because it will have more current capability.
However, the likelihood in domestic listening of getting anywhere near 60W output power is extremely low.
Now, the only issue with this is that the impedance seen at various frequencies is not constant, and will have dips and peaks. For the amplifier to cope with this it needs to have enough ability to supply the current demanded for any impedance seen when a voltage within the limits of the amplifier is required. Biamping helps give this additional current ability, and since impedance dips are most often seen in the bass region, it is best to have the more powerful amplifier drive the bass because it will have more current capability.
However, the likelihood in domestic listening of getting anywhere near 60W output power is extremely low.