Flex 6000 Digital Audio Encoding

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I'm looking at the SmartSDR Software Users Guide in the DAX section (starting on page 112) and I'm trying to understand what format the digital audio output in a DAX channel is?  I see that it is digitized audio but is it PCM or DSD encoded or something else?  This is probably quite obviously documented somewhere but I must be missing it.
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Richard McClelland, AA5S

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Posted 3 years ago

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Richard McClelland, AA5S

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I think that I saw the dax audio is in a 44.1kbps digital channel.  I'm not seriously into audio but I think this implies PCM encoding.

Along the same lines, in the Hardware Reference Manual, page 30:

"7.23 OUTPUTS [1, 2, 3]
Open drain digital outputs. Possible future product feature - not currently enabled."

Maybe Flex is planning to put the audio from the active slice to one of these outputs as DSD single rate (2.8MHz) or double rate (5.6MHz) raw.  This would be handy in order to route the audio directly to a DAC (e.g. http://www.psaudio.com/nuwave-dsd/) so that the audio wouldn't have to pass through a client computer at all.  Might also be possible to grab the audio from pins 12/15 of the ACC connector?
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Richard McClelland, AA5S

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So, to continue my rhetorical conversation, 44.1 kbps PCM audio available on an external connector should be more than sufficient for communications.  The audio purists amongst us might want to utilize 5.6 Mhz DSD so that they can post-process the audio to make it sound like they they are in the fourth row of the Temppeliaukio Kirkko as they listen to code emanating from the pulpit
(Edited)
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Ria - N2RJ, Elmer

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It's PCM and the sample rates I get from Windows are as follows

Since all it is is a virtual driver they could probably output any of those sample rates and bit depths without issue. 
(Edited)
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Richard McClelland, AA5S

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Thank you.  Do you see a way to get this PCM bit stream directly from the Flex 6000 rather than via DAX?  Not a high priority for me since I don't own a Flex 6xxx but I became curious after I saw a DAC vendor's claim that they could process any digital audio bit stream.  Seems like a circuitous path to go from the Flex to the computer to DAX then out via USB to a DAC. 
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Richard McClelland, AA5S

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Accommodating this particular DAC probably won't become an issue for Flex anytime soon since this thing costs almost as much as a 6700.
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Richard McClelland, AA5S

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On the other hand, Flex should hire their engineer because this guy is so eccentric that Flex could make a video like this and charge $16k for the next Flex:  https://www.youtube.com/watch?v=mRg-Rrd2blY.  Pristine clocks are essential for the discerning Amateur, after all.
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Ken - NM9P, Elmer

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Eric, if I remember previous conversations correctly, since you are using 24KHz sampling, it relatively easily can be scaled up or down to 8, 12, 48, etc. for use in other "sound card type" Digi software without all the conversion remainder errors, etc.?  Using the 44.1 KHz CD standard would be more problematic.
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Ken - NM9P, Elmer

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Eric, if I remember previous conversations correctly, since you are using 24KHz sampling, it relatively easily can be scaled up or down to 8, 12, 48, etc. for use in other "sound card type" Digi software without all the conversion remainder errors, etc.?  Using the 44.1 KHz CD standard would be more problematic.
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Sergey, R5AU

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Ken no sense how you are scaling in any way this is re-sampling with appropriate effects. You can try it ex. with Fldigi