does the sub have 2 sets of connections into the box ? if the box has 1 connection, then both subs are wired internally. with most 2 channel amps i've seen, to bridge the channels you usually wire up the + speaker outputs only. but don't quote me on this, call that company and ask. i don't have much knowledge with MTX.
looks like this amp can put out 500 rms into 4 ohm, so make sure the sub is also a 4 ohm. if the sub is a 2 ohm then the amp will probably deliver more power into 1 ohm.
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