the next test was a control on the PCM-A10 to see if the tests above (which showed the ICD-UX voice recorders to not be that far off the A10 at the maximum input level of the voice recorders), actually had the A10 operating it at its maximum dynamic range. Since the A10 can actually take a 16dB higher line in than the voice recorders at its least sensitive setting (input level 01 , 0dBFS = +12dBU), tests were conducted in both 16 and 24-bit with the same program material, and the mytek volume adjusted 16dB higher
+12 dBU is a pretty hot level for an unbalanced signal... lets see if it clips.
lookin good!:
the statistics on the noise floor at this level were improved quite a bit
pcm-A10 , 24/44 line in level 01 (+11 dBU), peak -0.9, -1.1 dBFS (L/R)
Left Channel Right Channel
Maximum sample value (dB) -82.969 -82.473
RMS level (dB) -96.128 -96.398
Integrated Loudness (LUFS) -Inf.
Loudness Range (LU) 0.00
Maximum True Peak Loudness (dBTP) -82.16
Maximum Short-Term Loudness (LUFS) -90.84
Maximum Momentary Loudness (LUFS) -90.79
-------------------------
pcm-A10 , 16/44 line in level 01 (+11 dBU), peak -0.9, -1.1 dBFS (L/R)
Left Channel Right Channel
Maximum sample value (dB) -84.288 -84.288
RMS level (dB) -90.309 -90.309
Integrated Loudness (LUFS) -Inf.
Loudness Range (LU) 0.00
Maximum True Peak Loudness (dBTP) -80.77
Maximum Short-Term Loudness (LUFS) -89.32
Maximum Momentary Loudness (LUFS) -89.26
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again we see the RMS noise measured below the limit of the 16-bit container
again we see the 16-bit file with a slightly lower peak noise floor than the 24-bit file (!) odd....
the hotter levels into the A10 definitely seemed to pay off.... we gained 5-7dB of headroom.
Impressive that the A10's input couldn't be brickwalled at its lowest input sensitivity . Its best performance apparently will always be seen with an input hot enough to get high levels with the input level set in the single digits.
since I was using the AD2K as a reference level meter i ran the same +11.5 dBU signal into the AD2K at 24/44 to see what the noise floor looked like there. Highest sensitivit yof the AD2K is 14dBU=0dBFS, so we see the peaks bout 2dBFS lower:
AD2K, 24/44 line in (+11.5 dBU), peak -2.5, -2.4 dBFS (L/R)
Left Channel Right Channel
Maximum sample value (dB) -97.567 -96.890
RMS level (dB) -111.239 -110.870
Integrated Loudness (LUFS) -Inf.
Loudness Range (LU) 0.00
Maximum True Peak Loudness (dBTP) -96.26
Maximum Short-Term Loudness (LUFS) -Inf.
Maximum Momentary Loudness (LUFS) -Inf.
of course the AD2K beats the A10 handily on noise level, by about 15 dB, but its a good reference by which to measure the line-in noise of the A10