View Single Post
  #16   Report Post  
Posted to alt.comp.os.windows-10,alt.comp.microsoft.windows,rec.audio.tech
Paul[_21_] Paul[_21_] is offline
external usenet poster
 
Posts: 9
Default Typical first pass tutorial process on Windows 10 where NONEof the extent how to articles actually tell you what you really need to do!

Paul wrote:
Arlen Holder wrote:

It's in understanding that final (fifth) planet lining up that I keep
reading (and re-reading) your response, gleaning a bit more with each
try.


You need a diagram of an HDAudio chip, as additional context info.

I'll find one later and post a link. I've posted
one before, just can't find it. The ones in Analog Devices
datasheets are pretty clear, for example, and you'll be
able to see the Stereo Mix in there.

Paul


What's interesting (to me), is the Stereo Mix is really a mixer,
but the software doesn't allow it to be controlled that way.
Stereo Mix is much more than just LineOut.

https://i.postimg.cc/dVDTpv8G/AD1988B.gif

Use "Download original image" to see the full scale version.

The picture was twice that scale, but the site wouldn't
accept it, so I had to scale it down a bit.

The AD1988B claims to use 32-bit math (to avoid overflow),
which tells me that parts of that diagram are digital and
not analog as the "functional" diagram might claim. The
mixer is doing the summation of 8 channels of 24-bit each,
so this would be 27-bits to avoid overflow. They don't say
whether it's fixed point or float, but fixed point
would be easier for them.

The diagram is kooky, compared to how the GUI on the
computer appears and works. It could for example,
be mixing 7.1 down to stereo, but with a transformation
or what ? Perhaps the driver just says "screw it" and
passes only LineOut through.

Paul