Originally Posted by Plasmoidial
The description of this product makes it sound like it can actually output HD sound from the SPDIF and not just in 2ch.
Of the formats the descrption listed only DTS, Dolby-AC3 (Dolby Digital) and HiFi Stereo (2.0 PCM) are compatible with SPDIF. All of the other formats would have to be actively converted into something SPDIF actually supported.
I tried it with the 360 and PS3 (which have no problems with optical out) and they did not work either.
The Xbox 360 only supports SPDIF compatible audio formats over HDMI so it should work your HDMI switch. (However, one of the audio formats the 360 suppports, "Dolby Digital with WMA Pro", isn't compatible with your Pioneer headphone box.) For your PlayStation 3 to work you would need to disable all the audio formats that aren't compatible with SPDIF and your headphone box.
Do the consoles and other units that have both HDMI as well as optical out simply have seperate audio processors for each? Why can the consoles do it, but not a standard audio box?
The Xbox 360 has essentially just two audio outputs, one for SPDIF and one for stereo analogue audio. The SPDIF output is useed for both the HDMI and optical outputs, this is why the Xbox 360 is limited to just SPDIF formats over HDMI. The PlayStation 3 has three, one each for HDMI, SPDIF and analogue so its HDMI output supports a much wider range of audio formats.
While both the 360 and PS3 both have CPUs powerful enough to encode dynamically generated 3D positional audio into Dolby Digital using only tiny fraction of their CPU power, only the Xbox 360 has a blanket licence to use the Dolby patented technolgy. With the PlayStation 3 games licence the technology on title by title basis, so not every game supports Dolby Digital. PS3 games can also support multichannel (5.1/7.1) PCM for surround sound over HDMI, and this doesn't need a licence. Other audio formats (eg. Dolby TrueHD, DTS, AAC) are only supported over HDMI or SPDIF (where compatible) if the original media being played (eg. Blu-Ray disc or a video file) uses ones of these formats. In that case the audio is bitstreamed without modification.
Nintendo went more the PS3 route with the Wii U, except they didn't implement any support for the now obsolete SPDIF formats. The only supported way to get surround sound is through multichannel (5.1) PCM over HDMI.
In order to connect your headphone box to your Wii U and get surround sound you need a device that's capable of converting the Wii U's 5.1 PCM HDMI output into Dolby Digital or DTS over SPDIF. In addition to the Dolby or DTS licence fee that would be required, such a device would need a powerful enough CPU to do the encoding. Add in the software development costs and you're adding at least $100 to the cost of the device, all for something with a very limited market. The Wii U might have created enough of a demand for such a device, but I wouldn't hold your breath waiting for one.