How would you get XLR into the iPad ??..
OK. I found THIS
Cakewalk UA-4FX USB Audio Interface/MIDI Interface
You get 24-bit/96kHz audio resolution, if the iPad records at that quality, that would be ok.
THEN use the camera / usb adapter for the iPad and go from there. Does the iPad have a good audio program for noise removal and audio sweetening ???
I still think a dedicated recorder would be best, because you want to have the recorder be mobile along with on your Boom Op. If you are doing a fixed video setting where you are on a set and not moving, or interviews...maybe
EDIT
The Rode Videomic Pro is not well suited for Boom use. I suggest a mic w/ XLR cables to shield against noise from electrical sources. The Rode Videomic Pro is for mounting on top of the Cam, does not work well in an Indie film set. You need that Mic close to the mouth of the talent. Like within 2 feet close. The Rode Videomic Pro is OK for quiet, static settings where you can get the cam close to the talent.
As for the iPad but if you have the tool available and it will get a good signal..why not ?? the Audio interface costs less than a Zoom or Tascam, I suggest you find a decent Hyper Cardiod mic for outdoors and a Cardiod for indoors use on a boom pole w/ XLR out.
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