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SPDIF (S/PDIF) outputs 2 channels?


Active Member

So I'm trying to use SPDIF passthrough (optical) to get DTS 5.1 from my PC to my Z-5400 sub. Ideally I want the sub to be doing all the decoding.

The control station of my receiver shows dts 3/2 when I use ac3filter with 'Use SPDIF' checked, and sound comes from all 5.1 sources. However, the Pin Info (Out) in ac3filter shows "Audio: 0x0092 48000Hz stereo 1536Kbps".

Does this simply mean the DTS 5.1 information is being sent on 2 channels and then decoded at the sub, or something else is going on?



Active Member
SPDIF naturally only has enough bandwidth to send out uncompressed 2 channel audio. The way they pump 5.1 through it is encoding formats like Dolby Digital and DTS. It will play 5.1 when it has a 5.1 DD or a DTS encoded source going through optical.
Whenever it doesn't it is just 2 channel stereo which is why you see that infomation.

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