Sound Devices 744t - Preamp / Self noise or Mic?


Recently purchased a used Sound Devices 744t and have been very impressed with it in general, however as purchased 2nd hand I have had some minor worries about it (most of which are probably unfounded), wondering if things I am surprised about are "normal" or if it's because its used.

One thing that I have noticed is the very minor difference in noise floor in my recordings compared to the Sony PCM-M10 which I was using previously. The mics I am currently working with are not particularly high-end which will probably no doubt be the answer to this question and I am guessing that any noise I am hearing is probably attributable to them instead of the SD, however I just wanted to check with those here first that may be able to compare somewhat.

Today I decided to try test to see what was going on. Set up an NTG-2 and an NTG-3, then an NT4 and also a Behringer XM8500 dynamic mic next to each other feeding channels 1 & 2 on the SD 744t, and then set up a digital metronome about 2 feet away. Balanced the input gain each time so they were peaking at -12dBFS.

Setup was Phantom power on, gain range normal to off, no low cut, recording at 24bit/96Khz. (phantom off for the Behringer)

In post I normalized each recording to -1dB.

Here are both files at original bit/sample rate:





Now there is certainly less noise with the NTG-3 as expected and even less still with the NT4, but that could also be attributed to the fact that it required a good deal less input gain to reach -12dBFS peak than the NTG-2 or XM8500 while recording.

Do these results appear normal/expected to those who have experience with the SD recorders? Is it simply my mic's just have a much higher noise floor than the SD 744t and all I am hearing now is their own self noise? I am quite happy if that is the case for now, just want to be %100 sure there are no issues with the SD unit I have considering it being 2nd hand.

I have tried with various XLR cables and switching the mic inputs (for the mono mics) on the SD 744t but the results remain the same each time.

Many thanks for any feedback on this.


Posted 2014-12-30T03:30:46.880

Reputation: 61

No answers