Originally Posted by Rhino73
"I'm of the opinion that a lot (most) of A/V receiver do not come with built in realistic headphone surround sound.
But they use word play to make it sound like the A/V receiver does"
Could you explain what "realistic headphone surround sound" is?
I make no claim to being an "expert" on headphone surround sound.
But to me for realistic headphone surround sound, you need to start off with 5.1 (6-channel) or 7.1 (8-channels) of digital audio.
Those separate audio channel are then processed down to 2 channels of specialized audio, which is sent to the 2-channel stereo headphones.
This 2-channels of specialized audio is designed to make your 2 ears think they are hearing surround sound.
Someone figured out how with only 2 ears, our brain can tell where a sound is coming from and now use the stereo headphones to mimic surround sound.
But you need to start out with a source that has fully 6 (or 8) separate audio channels.
An old trick in the past when video recording only had 2-channels of audio (one audio signal per channel), was "Expanded Stereo" (fake surround sound), where 2-channels of audio was expanded up to 5.1 or 7.1 speaker audio, it got people to buy 6 or 8 speakers instead of only 2 speakers.
I'm guessing "Expanded Stereo" was later modified for headphone use, it's an older (cheaper) technology that companies can add a modern name to.
Harmon/Kardon calls their "Expanded Stereo" of headphones Logic 7.
Expanded stereo is also one of the older features of Dolby Pro Logic.
Dolby Pro Logic has been around for about 20 years (or more) every few years there would be revisions, with new features, latest is Dolby Pro Logic IIz (2009).
When a modern A/V receiver is manufactured, the manufacturer has a choice of using older Dolby Pro Logic, which is cheaper,
or using the most modern, like Dolby Pro Logic IIz, but they all get to put on their receivers the title "Dolby Pro Logic".
Dolby use to be able to encode 5 audio signals into the 2 audio channels of a VHS tape (older Dolby Pro Logic)
Your later model VCRs use to be able to separate out the 5 signals of audio from the 2 audio channels,
but I doubt you could get the same audio fidelity as you could with modern DVDs and Blu-ray disk,
which come normally with 6 fully (maybe 8) separate (high fidelity) channels of audio already on the disk.
Others on Head-Fi believe that the most modern version of Dolby Pro Logic (IIz) is capable of processing realistic headphone surround sound, but I'm still investigating.
Edited by PurpleAngel - 7/21/14 at 1:28pm