Out-of-Head Virtualization Circuit

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Listening music through headphones is a necessary compromise for me. I have always been disturbed by the in-head image. I read it somewhere that it is possible to simulate the effect of the head and the ear canal, that is how the soundfield coming from the loadspeakers is modified until it reaches the ear drums. It seems quite easy: some delay from right to left channel and the way around, some freqency response modification, some frequency dependent crosstalk.
My question is: why are such (let's call it) "soundfield processors" not more common? Is it possible to realize such circuit around 2-3 opamps?
Perhaps one can plug a tiny electret microphone in the ear canal, put some test signals on the loudspeakers, and use some clever software to calculate the cross correlation function, or whatever needed to modify the audio signal of both channels..
 
crossfeed (which is the term you are looking for I think) is not so popular mainly because there have been some pretty sub-par realizations of it. the meier crossfeed amps are pretty decent, but imo it does not really suit all headphones, or all music. it takes more than a few opamps, but yes you have the idea.

there is also a more involved HRTF system (HRTF is the senses way of localizing sound and our environment with only 2 ears) called the Smyth Realizer, which you actually calibrate to your own personal HRTF senses and tracks your head movements and comes with a pretty standard stax electrostatic headphone system, but the corrections and algorithms allow for other high quality headphone systems to be used, as long as yo0u calibrate a setup file wearing those headphones
 
There are plenty of software applications of crossfeed. J-river has a native plugin that works quite well.
I have tried quite a few. Problem is, after a while there seems to be a slight loss of resolution: the whole presentation is overly softened, and there is a loss of extension in bass and treble as well. Bass in particular has a tendency to become one note. Yes, it seems a bit more "natural", but going back to standard unprocessed stereo, the music is clearer and more present.

Hardware implementations are rarer. Smyth realizer is the most advanced one, and according to some french friends really worth the try. Another one which seems to lack the forementioned drawbacks of crossfeed is the SPL Phonitor. It gives you the ability to simulate precisely the virtual position of the speakers (the Phonitor was designed to be used as a studio mastering tool).

Here is some info about crossfeed and headphone psychoacoustics:
HeadWize Library - Technical Papers
 
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I figured the Smyth would come up, it seems like the ultimate. I really would love to hear one. The Phonitor looks interesting for a slightly lower price. The one thing that bugs me about the Smyth is that is seem only to emulate rooms and speakers so you're stuck with what someone else has done. Is that a big limitation, or not?

Having tried, and not liked, many software and passive crossfeed and headphone enhancements, maybe the full on hardware is the way to go.
 
yes apparently the Smyth is really excellent, ive heard the combination of custom in ear monitors with the smyth is to die for. i can imagine this too, because my jh13 have probably the most pinpoint accurate imaging and detail i've ever heard from any audio reproduction system, but its more in your head than outside the head, so combined with the svs it should be brilliant.
 
Are any processed music tracks available on the net?

BTW back in the 70's I made some "dummy head" recordings with small electret capsules plugged in my ear. It was very realistic when I played them back through headphones. Sounds coming from behind me was an unbelievable experience. Everything was out-of-head, of course.
 
Are any processed music tracks available on the net?

BTW back in the 70's I made some "dummy head" recordings with small electret capsules plugged in my ear. It was very realistic when I played them back through headphones. Sounds coming from behind me was an unbelievable experience. Everything was out-of-head, of course.

You can search for binaural music... like this:
Snakecharmer Binaural by Ottmar Liebert and Luna Negra - YouTube

I heard the whole album. It is brilliant!
Somtimes visit the head-fi music recommendation topics, to find extraordinary albums.
 
I built the Meier with crossfeed some years ago and am very happy with it. I use the 'normal' crossfeed, not the bass-enhanced, and for chamber music such as string quartet it is great, bringing the soundstage forward just a bit.
My current headphone amp is the van Waarde (also described on the Headwize site) and I plan on adding crossfeed to it at some time (between the two tube stages).
Another method I have used with good results is to process the music using Canz3D (do a Google search) and an audio app such as Audacity (I use Audio Hijack on a Mac). In fact, the results with Canz3D are very good but it requires making a new copy for each piece of music. (Or you could listen in real-time from the computer I suppose.)
 
I figured the Smyth would come up, it seems like the ultimate. I really would love to hear one. The Phonitor looks interesting for a slightly lower price. The one thing that bugs me about the Smyth is that is seem only to emulate rooms and speakers so you're stuck with what someone else has done. Is that a big limitation, or not?

Having tried, and not liked, many software and passive crossfeed and headphone enhancements, maybe the full on hardware is the way to go.

There will be a Smyth Realizer at Burning Amp 2017 that may be set up for demoing (for those who are not scared by its looks!), and that WILL be raffled off to one lucky winner!
 
The Darin Fong Out Of Your Head software (demo version) does not give any sound on the audio output, although the green bar is moving in the audio mixer. My PC is using windows 10.

I found another one: Razer Surrond, but it does not work either.

Has anybody found a working (free) alternative for Windows 10?
 
I built a simple breadboard circuit that was detailed on the Bottlehead forum several years ago that worked quite well, although I've never heard a commercial product to compare it to.
 

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