Topic: Noisy microtrack

[scoper]

More testing, 1/8" input

Line In, 0 gain:  -80.43 dB   -90.81 dB
Line In, Half gain: -74.03 db    -84.14 db

Mic in "M", 0 gain:  -72.28 dB   -82.43 dB
Mic in "M", half gain:  --66.84 dB   -76.47 dB

In each case, 10 db more noise in the left channel.... hmmm...

Also in each case, much greater noise level. The only difference between this and the prior test was that I didn't use the converter dongle for TRS input.

Any comments?

[guysonic]

Here is the noise graph with 1K ohm-to-ground input load for both types of input.  TRS input has two resistors each channel from ring/tip to ground for these tests

[atomota]

More testing, 1/8" input

Line In, 0 gain:  -80.43 dB   -90.81 dB
Line In, Half gain: -74.03 db    -84.14 db

Mic in "M", 0 gain:  -72.28 dB   -82.43 dB
Mic in "M", half gain:  --66.84 dB   -76.47 dB

In each case, 10 db more noise in the left channel.... hmmm...

Yeah . . . I just got a Microtrack.  I did some voice and classical guitar recordings, about 2 feet from the T-mic. M setting, level all the way up, 27dB boost off, 24/44.1, and man, the noise is pretty well unbearable.  Noise is -52dB, average signal RMS for the guitar recording is -25dB (-6dB peak).

I thought I would be able to clearly hear the clock ticking in the room, but it's completely lost in the noise.

So I did a bunch of tests.  I put 1.2K metal film resistors across the 1/8" inputs.  Best case noise (L, min level) was -79.8dB, worst case was -55.5dB (H, max level). So the T-mic is noiser than a 1.2K resistor.

For the TRS I just shorted the inputs and for the left channel I got -99.1dB at L + min level, -74dB at H + max level.  The right channel was 3dB to 10dB noisier (opposite of the figures quoted above).

Clearly the -100dB noise figure quoted by m-audio is best case.

Clearly I don't have to bother making 24-bit recordings.  Looks like I'll need to post-process with noise reduction software. Looks like I won't be keeping the Microtrack after my current project.

I wanted an R-09 but it wasn't shipping yet, and probably still isn't.  I hope it's cleaner than the Microtrack.