Switching MOSFET with Hall Effect Switch in battery powered device

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k2panman

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I am designing a circuit to switch a MOSFET to power an audio amplifier at about 30 Watts, using a hall effect switch to gate the MOSFET. Power will be a 26V 700 mAhr LiFePO4 battery pack, which I want to conserve as much as possible. I only occasionally need to switch the device on - it will sit for a few days or weeks in the off position, then be switched on a few times a minute for short (10-20 sec. periods) for an hour or so. I'd like to not drain the batteries significantly when not in use, and not have to recharge more than necessary.

My issue is that the hall effect switches all pull to ground, and N channel MOSFETs need the gate to go hi to switch on. What would be the simplest, most elegant (reliable) circuit to do this? :?:
 

transistor or FET or MOSFET in common-emitter mode between the switch and power MOSFT
 

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