I hope this is the right forum - I looked at all the Stack Exchange communities, and this seems the best fit...

As a musician, engineer, and home AV enthusiast, I encounter various digital audio bitstreams from stereo SPDIF to Dolby Digital 5.1, to DTS, Atmos, etc. These can be transported over various physical media - Coax, Optical, HDMI. When things don't work, I find I spend an excessive amount of time debugging.

I'm looking for a tool to help diagnose these bitstreams better than trial and error - answering the questions: is there a signal, and if so, what is the type?

Such a tool could be implemented as standalone hardware or software that runs on Linux or Windows. Even a Raspberry Pi should have sufficient capability to identify the bitstream. I've been searching and have found nothing like this.

If I have to roll my own, the best information I found (on DD only) is at Wikipedia which links to the ATSC AC-3 standard That also points to a decoder liba52 which was last updated in 2002. Can anyone offer better suggestions on a place to start?

  • A nice AudioPrecision audio analyzer with the appropriate interfaces (ap.com/analyzers-accessories/interfaces-modules) will do the job. Not cheap, though.
    – audionuma
    Nov 29, 2021 at 13:04
  • As @audionuma points out, there exists test equipment in the $$$$ price range. As far as I can determine there is nothing available in terms of DIY hardware or open source software. One option of last resort is to buy a cheap receiver with the appropriate inputs, and look at the front panel display. Not very compact or convenient, though.
    – tim11g
    Dec 5, 2021 at 23:55
  • I ran across this post on a [DIY SPDIF transceiver](hackaday.com/2021/12/06/… ) for the Raspberry Pi. It is out of stock unfortunately. It tells me there may be some built-in SPDIF decoding capabilities already in the Pi. I'll study and report back.
    – tim11g
    Dec 11, 2021 at 21:22


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Browse other questions tagged or ask your own question.