1 Topic by gracky (edited by gracky 2017-12-19 15:14:32)

  • Registered: 2017-12-19
  • Posts: 9

Topic: Q on 384Khz compensation filter.

(My excuses, I'm not an owner of ADI-2s but I came to be interested in it recently and was looking at their manuals.)

According to the manual (p.85), it looks like that the 384K compensation filter is active whenever the sampling rate is 384K and cannot be deactivated. But it seems that the cause of the high frequency rolloff the filter compensates is that the DAC chip fixes the DA filter on slow one at 384K (p.84). So when the user chooses slow filter or NOS filter, isn't it more compliant with the user's intention to deactivate the compensation filter leaving the effect of the slow filter fixed by the DAC?

Another question, is the 384 filter applied to ADI-2 DAC also?

Best,

2 Reply by MC

  • MC
  • MC
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Re: Q on 384Khz compensation filter.

The filter used above 192 kHz is not documented by AKM. It seems similar to the slow one, that is true. Anyway, the user couldn't care less as at 384 kHz the filter (any filter) has zero influence on the sound: the rolloff is far above the audible range, and any ringing requires a) a triggering signal of around 192 kHz which would b) cause a ringing with 192 kHz. That will never happen, because music material is usually not available at 384 kHz PCM, and even if does not include such frequencies. So we don't even need to discuss if that would be audible or not.

The correction is for measurement purposes and also has no influence on normal audio signals.

Added: Forgot to mention that the digital correction filter is not present in the DAC version.

Regards
Matthias Carstens
RME

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