This amplifier is the best combination to the 1259 subwoofer for mid budget.
Keiga is one of the leaders in the subwoofer amlifiers as well as Dayton.
It supplies 300 Watt power at 4 Oms, 0.1%THD and 360 with 10%THD
General THD is 0.08%
You have the important option to hook it with your stereo loudspeakers while it takes it share in the frequency range at leave the rest to the speakers. You can control this with the crossover knob in addition to the gain.
You can also make phase 180deg inversion (do not use this if you place the sub at the same line as the speakers.
Disadvantage: too short and thin cable supplied.

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