I'm new to field recording and I have a 744t, but channels 3&4 have to be line in. So if I want 4 mic channels, let's say Rode NT4 on 1&2 and Line Audio CM3 on 3&4, I need to get the 3&4 up to line level before they'll work. Last night I tried just plugging a mic into channel 3 and turning the gain up, but I had to turn it all the way up to barely hear anything.

I know in the studio a mic preamp would do this, but is there anything that would do that out in the field? a preamp or DI box or something? if you could let me know what people use that would be excellent. It seems like the MixPre-D, but what I've read only refers to it as a mixer, and I'm not sure if a bunch of gain on the MixPre-D and then even more gain on the Line level input would just equal a bunch of noise.

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Yes, you are correct that inputs 3 & 4 require line-level. You have done your own experiment to show that there is not enough gain to handle microphone-level. Note that Sound Devices gear is pretty much on the top of the heap of audio gear. It has a few peers, but generally regarded that there is none better.

In the same manner the SD MixPre-D is very highly regarded as one of the best in portable, clean microphone preamps. The MixPre-D is both a "mixer" and also good, clean mic preamps. So it is ideally suited as extenal mic preamps for your 744T recorder. Probably most people use the MixPre-D as clean mic preamps to feed into their camcorder (or Zoom shaver-recorder, etc.)

There are probably hundreds (or thousands) of MixPre-D out there being used as mic preamps for extra inputs for the 744T or similar recorders. So you are in excellent company.


Depending on how you want to organise your gear, you can also consider purchasing a couple of Sound Devices MM-1 units which are high-quality battery-operated pre-amps - typically suited to boom-operator belt-buckle useage. Your other issue with using microphones directly into line-input connections is that you are unlikely to be able to supply them with any phantom power. Lucky you could hear anything at all in your case.

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