HDMI audio VS Optical Audio

[bangbang]

I read on http://www.cnet.com/news/hdmi-vs-optical-which-digital-audio-connection-to-use/

that the only difference between the two, is that optical can't put out Dolby TrueHD or DTS HD Master Audio.

If I use one of these to connect a PS4 to my HD CRT TV as well as converting either the coaxial or 3.5mm output to stereo audio inputs on my TV,
would Dolby TrueHD or DTS HD Master Audio still be able to be accessed? or no ?

[johns0]

Nope,only on hdmi,coax is limited.

[Cornucopia]

There is an obvious physical & electrical difference, and an obvious protocol difference, but the important usage difference is in bandwidth/capacity.
"TOSLink" is an optical version of the electrical coax SPDIF connection protocol.
SPDIF supports only 2 channels of uncompressed LPCM audio at up to 20bit depth and 48kHz sample rate (<=1920kbps), or lossy/lossless compression methods which will fit within that bitrate (with enough room to spare so that the signal can be "masqueraded" as LPCM but with recognizable signature flags & padding).

Since most forms of uncompressed/lossless, multichannel/high-samplerate/high-bitdepth audio (including TrueHD and DTS-HD-MA) will exceed the limit during their peak bitrate moments and/or on average, they won't work.

Another difference is that, since HDMI includes both the video & the audio together in the same data stream, the likelihood of getting out-of-sync is much less than Optical.

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Unless that above-mentioned device specifically supports decoding TrueHD or DTS-HD-MA (and I truly doubt it, given the price - I doubt it can even decode/downmix lossy formats), it would "negotiate" with the HDMI source advertising that it is a LPCM sink. Output would then depend on how you set the PS4, if it (the PS4) can do it and is set to internally decode most streams (including TrueHD and DTS-HD-MA) and downmix to stereo, then yes you should be able to "access" and hear it.
But if you try "pass-through", the only signals which would work would be the truly LPCM stereo signals.

This device is handy if you previously had NO other option than an HDMI source.
If you have SPDIF/TOSLink options on your receiver already, it is your best bet until you can afford to upgrade to an HDMI-capable audio receiver (with TrueHD & DTS-HD-MA decoding built in). I have 2 receivers currently at this stage.

Scott

[bangbang]

Nope,only on hdmi,coax is limited.

alright thanks man



thanks Cornucopia,
i think i'll just go the toslink route as there's nothing to be had,
whichever's cheaper