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Topic: Clicks with Firmware 26/24

Moved posts over here.

Regards
Matthias Carstens
RME

2 (edited by jiw 2018-11-28 19:13:58)

Re: Clicks with Firmware 26/24

MC wrote:

- When changing between two EQ Presets where one had a high cut at a low frequency, and the other one had a high cut with a very high frequency, a short click sound occurred.

I have described clicks occurring occasionally during changes of the filter types for bands 1 and 5 if a signal is present via mail to MC.
With the new firmware, I can still reproduce it.
Using -20 dBFS RMS pink noise, this even produced a click that overloaded the device. Output was Line Out, Vol was -32 dBr, PEQ was enabled and Loudness was enabled with boosts at default values (7 dB) and Low Vol Ref at -38 dB.

Even without any EQ of any kind except band 5 at 0 dB gain at 5 kHz with Q of 0.5, it produced a click indicated at ~12 dB above the level of attenuation, ~-9 dB for Phones at -36 dBr.

The parameters for the PEQ for Line Out are:
B       G         F      Q
1   -2.0      150   0.5
2   -2.0      150   1.3
3    0.0      500   1.0
4    0.0   2.000   1.0
5    0.0   5.000   0.5

All tests were done at 44.1 kHz sample rate using USB input.

EDIT: Added that Clicks appear with signal present. Edited part is in italic.
EDIT2: I don't think this would significantly change MC's response. So I will address it as is.
EDIT3: Clarified that I also changed filter type with Phones although all filters were set to 0 dB gain. Again, edited parts are in italic. This omission must have put MC off.

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Re: Clicks with Firmware 26/24

jiw wrote:

I have described clicks occurring occasionally during changes of the filter types for bands 1 and 5 via mail to MC.

I checked my mails and I have no such mail from you. I have 3 mails from you that discuss a left channel click at sample rate changes during music playback, nothing else.

jiw wrote:

With the new firmware, I can still reproduce it. Using -20 dBFS RMS pink noise, this even produced a click that overloaded the device. Output was Line Out, Vol was -32 dBr, PEQ was enabled and Loudness was enabled with boosts at default values (7 dB) and Low Vol Ref at -38 dB.

Even with no EQ of any kind, it produced a click indicated at ~12 dB above the level of attenuation, ~-9 dB for Phones at -36 dBr.

So it seems we are not talking about EQ-based clicks here at all. And the click that you still have and describe above has not been addressed, and I explained to you why we won't address it, and that it is no issue in real-world usage (a change of the sample rate during continuing music playback. Usually the playback is stopped before the sample rate change.).

Regards
Matthias Carstens
RME

Re: Clicks with Firmware 26/24

I see that I should have written more clearly that I also changed the filter type with Phones although all filters were set to 0 dB gain. Technically, in its original form as quoted by MC, it is incorrect, as I did no such test.

I have edited the previous post accordingly and hope that this clears up the confusion that may have arisen from my poor writing.

MC wrote:
jiw wrote:

I have described clicks occurring occasionally during changes of the filter types for bands 1 and 5 via mail to MC.

I checked my mails and I have no such mail from you. I have 3 mails from you that discuss a left channel click at sample rate changes during music playback, nothing else.

I sent you four mails in said exchange. I sent these mails to the mail-address which you used to write me in the first place and also today. All the mails I addressed to you using that address are marked as sent on my end. 

I will forward you the message (No. 4) that you must have missed. It says less about the clicks from the PEQ filter type change than my previous post but also includes some feedback on USB Firmware revision 25 (which might be relevant for USB FW 26).

I suggest that if we want to determine what might have went wrong with the mail exchange, that we do so in private.

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Re: Clicks with Firmware 26/24

Unfortunately that fourth mail never arrived, thanks for sending it again. I will check the EQ setting that you list. The other low volume click mentioned that happens changing from 44.1 to 96 kHz (I quote: low volume, partly masked by the signal) is in our opinion caused by the used playback software, and not something we have to further examine.

Regards
Matthias Carstens
RME

Re: Clicks with Firmware 26/24

Occasionally, switching the PEQ off also produces a click.

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Re: Clicks with Firmware 26/24

Correct. As does changing from Low Pass to High Pass in band 1, and from Peak to Low Pass in band 5 (your last report). All these clicks are random, seldom and not critical. Their removal would require too much effort and reduce the DSP efficiency, so we decided not to change this, sorry.

Regards
Matthias Carstens
RME