Buzzing when Trying to Connect Digital TV with Only Digital Audio Output to an Old Denon Receiver with only RCA Inputs

[Dansktex]

Mine is a similar problem to the one I read in an older thread which is now inactive. I have a Philips TV. It's sound system is Dolby Digital AC3. It's only sound output for connecting to my old Denon Receiver is Digital Coaxial Audio (for an S/PDIF cord). My Denon only has sound input via RCA cable. I bought the S/PDIF digital audio cord to connect from the TV, an HD Digital to Analog Converter (24- bit incoming stream S/PDIF to R/L RCA), and a red/white RCA cord. When I connected it all, I got the buzzing sound that others identified in the previous thread. Do I need to try the CE Compass device that was suggested there? Do I give up? Anyone got any specific idea of what to do?

Here is the link to the former discussion: http://www.tomsguide.com/answers/id-2017347/digital-audio-buzzes-motorboat.html

 

[americanaudiophile]

Many DACs will not work with a 5.1 DD stream only with 2 channel PCM. Your options are to go into the TV menu and see if you can change the digital output to 2 channel PCM or to get a DAC like this one
http://www.parts-express.com/parts-express-dac-digital-to-analog-converter-%2851-compatible%29--180-999

 

[Dansktex]

Thanks, americanaudiophile, but I already tried something similar; that's what gave me the fluttering buzz sound. I did much more research after posting my question and discovered that adapters (such as what you recommend and which failed for me) do not work with some of the more exotic versions of Dolby. The articles implied that a decoder rather than an adapter would be the answer and had worked with others. My digital sound output from the TV is Dolby AC3. I looked up the CE Compas Digital to analog decoder which had been recommended, and its specifications mentioned that it decodes AC3. Therefore, I've ordered one through Amazon from China (apparently available in the US only through Amazon now) and will try it when it arrives in about 4-6 weeks. Here's the link to the item:

http://www.amazon.com/CE-Compass-Digital-Coaxial-Headphone/dp/B008U23F3E

 

[americanaudiophile]

The DAC I linked to is compatible with 5.1 and I have used it just as you would,
Dolby Digital (originally called AC3) is the most common digital surround sound codec since it is is used for all broadcast TV programming. DVDs all have AC3, some have DTS and AC3 but almost none had DTS alone. BD disc have variety of codecs but all have AC3 too. So a 5.1 channel compatible DAC will work with DD / AC3. The one you ordered will be fine.
On some TVs you can select a 2 channel PCM output that will work with audio oriented DACS. A 24bit DAC would be stereo oriented.