How Do I Separate HDMI Audio From Video?

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Q I just bought a Roku 2 streaming box that only has one output type: HDMI. My Adcom preamp-processor lacks HDMI switching, however, so I am forced to connect the Roku to an HDMI input on my Samsung TV and use its optical digital output to route audio signals to the Adcom. My problem is that the Samsung TV only passes two-channel audio through its digital audio output. Is there a reasonably priced device that can separate 5.1 digital audio from the HDMI signal, or am I stuck forever with two-channel sound? —Joe Simone

A It’s unfortunately the case that many TVs only pass two-channel audio from their optical digital output. There are a few inexpensive devices on the market that will do precisely what you’re asking, however. Go to and do a search for HDMI to HDMI + Audio Extractor. You’ll call up a number of converters in the $35 range with names like J-Tech, ViewHD, and AGPtek that feature an HDMI input plus an optical digital output for routing 5.1 digital audio to a non-HDMI receiver or pre-pro. Such converters also provide an HDMI output to pass video on to your display.

Another device, the Octava HD11-ARC HDMI Audio Converter, has similar features but adds an EDID emulator that can “force” your HDMI source to output a 5.1 signal even when the connected display only supports two-channel audio. This apparently provides extra assurance that you’ll get 5.1 audio. The Octava converter’s HDMI output also has ARC (Audio Return Channel), which lets you route the TV’s built-in audio—from off-air digital broadcasts, Netflix, etc.—back down the HDMI pipe and out through the HD11-ARC’s optical digital ouput. It costs $150, but if you have a particular need for that feature, it’s probably worth it.

prerich45's picture

You can also use a HDMI De-embedder like the one from Atlona (HD-570) or the one from Essence - the Evolve. These will output video in one stream and take the audio and output it via optical or analog outs (5.1/7.1). Your receiver would need 5.1/7.1 multi-inputs for this.

frodo582's picture

which model of samsung tv do you have? As far as i know they all output DD5.1 and DTS 5.1 through optical output. You just need to change the Digital Audio Out settings from "PCM" to Dolby digital in Sound menu