Some of the Sunfire subs are notorious for being noisy. You should contact Sunfire about this problem and discuss it directly with them.
As to the isolation transformer pictured, it looks WAY too small to pass 2000 KVA with low distortion. Then again, it is hard to judge how big the core actually is going by that picture, as there are only the wires and heads of the bolts holding it together to gauge the physical features by. This wouldn't introduce hum into the sub at idle, but it could introduce other distortions at higher power demands. Sean
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As to the isolation transformer pictured, it looks WAY too small to pass 2000 KVA with low distortion. Then again, it is hard to judge how big the core actually is going by that picture, as there are only the wires and heads of the bolts holding it together to gauge the physical features by. This wouldn't introduce hum into the sub at idle, but it could introduce other distortions at higher power demands. Sean
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