IMPORTANT POINT: As with many ARC power amps, the "common"/O/-/negative output terminal of your VT-100 MkII is NOT ground. The 4 ohm output terminal is what is grounded.
Looking at the schematic for your amp at the ARC Database site it appears that the 4 ohm output terminal is connected to chassis/AC safety ground on both channels, and chassis/AC safety ground is connected to circuit ground through a 10 ohm resistor located in the right channel circuitry.
Therefore, given that you will be using two subs, I believe the connections should be made as follows:
1)Connect BOTH the red and yellow wires from each sub to the 8 ohm output terminal of the amp for the corresponding channel.
2)Connect the black wire from each sub to the 4 ohm output terminal of the amp for the corresponding channel.
3)Continue to connect your main speakers in the normal manner, as you have been doing (black/negative to "O"; red/positive to either "4" or "8" depending on the impedance of the speakers and on what sounds best).
Also, see this thread, although it pertains to ARC monoblock amps.
Regards,
-- Al
Looking at the schematic for your amp at the ARC Database site it appears that the 4 ohm output terminal is connected to chassis/AC safety ground on both channels, and chassis/AC safety ground is connected to circuit ground through a 10 ohm resistor located in the right channel circuitry.
Therefore, given that you will be using two subs, I believe the connections should be made as follows:
1)Connect BOTH the red and yellow wires from each sub to the 8 ohm output terminal of the amp for the corresponding channel.
2)Connect the black wire from each sub to the 4 ohm output terminal of the amp for the corresponding channel.
3)Continue to connect your main speakers in the normal manner, as you have been doing (black/negative to "O"; red/positive to either "4" or "8" depending on the impedance of the speakers and on what sounds best).
Also, see this thread, although it pertains to ARC monoblock amps.
Regards,
-- Al