I've been obsessed with surround sound over headphones since the arrival of our two children. My surround system was banished from the living room to the loft and the receiver sold. The main tower speakers at 40lbs each were too dangerous to have around and in any case in a small house it was impossible to crank up the volume at night time when they were gone to bed.
My main port of call for a few years was dolby headphone processing. I got a Philips processing unit for a few hundred euro that came with wireless 'phones and was reasonably happy. I could crank it up but the effect while good was not the same as real surround.
In the meantime I was following the progress of the Smyth Realiser. This was the brainchild of two brothers from Northern Ireland, one of whom had developed the DTS algorithm. It finally came to market in 2009 and I got one at the start of this year. What it does in effect is mimic on headphones the performance of any speaker system you calibrate from so that the result is almost indistinguishable from the real speakers. The process involved is as follows:
1) You input microphones in your ears and by putting test tones through your speaker system it measures how your ears hear the sound. If you don't have a full system you can make a 5.1/7.1 measurments from two or even one speaker. by changing your orientation.
2) With the microphones in your ear it calibrates the interaction of your ears with your headphones. This is a separate process from step 1) and can be done anytime. You would need to do a measurement for different makes of headphones as their interaction with your ears will vary.
3) Combine one and two for a complete calibration.
So, how does it work, in a word - magnificiently. I did my calibration using two Definitive Technology tower speakers with in built powered subwoofers. First it measured front left and right speakers (from which it creates a phantom centre). I then turned around and by changing my distance to and from the speakers measured for a 5.1 and 7.1 set up. (you can do as many calibrations as you want). My first test was from a demo disk that had the airplane chase scene from the third Indiana Jones movie. The sense of surround as the planes wheeled and crossed each other was perfect. The sense of presence from the front and centre speakers was uncanny. It truely sounded like my Def Techs were still in the room. The system also comes with a headtracker. This is a small transmitter attached to the top of your headphones. You put a small receiver in front of your screen, and then as you turn your head the sound stays in place as it would with a real speaker system, vocals are still coming from the centre of the screen and the volume increases in one ear and decreases in the other. Psychologically this helps to complete the sense of the sound coming from outside your head.
I watch a couple of movies a week and listen to a few albums as well. I did a separate stereo meaurement toeing the speakers in a bit more than I would for home cinema. You can mix and match speaker calibrations and headphones. You have four presets that you can pick from and compare on the fly and it only takes a minute to change any one of these for another stored calibration. The only performance downside is that you miss the visceral impact of deep bass. Bass on my Stax is very deep but obviously there isn't any air being shifted around the room to feel in your gut. Some people in the States have added tactile transducers to their chairs to compensate for this, but it doesn't bother me.
If you are lucky enough to live in LA there are a couple of studios where for a couple of hundred bucks you can calibrate from their $250k+ set up. I'd love to find some place in Ireland or the UK that would offer this facility. Access to a high end set up for calibration adds a lot to the system. It does come with one demo calibration, but as this is not personalised to the ears of the buyer it will not be as good as a proper calibration.
The cost of this is $3,360 plus whatever the VAT and customs charges would be in your location. That includes a Stax 2020 speaker/amp combination. It was a few hundred cheaper when I bought it and as I had a Stax 3030 already they knocked off several hundred more. (an added bonus - it somehow slipped under the VAT mans radar:)
The only comparable system that I am aware of is the Beyerdynamic Headzone. This however does not have personalised calibration, although it does allow extensive changes to its performance parameters. WHF gave it three stars a few years ago. It retailed at £2,000 (its about 25% cheaper now) and their opinion was that while it was good it was too expensive for what it did and their version of headtracking didn't work very well.
I would love if WHF could get their hands on the Realiser to review. Smyth Research have started to add European distributors but nothing in the UK yet (even though they have an office in Belfast) While it is very expensive (maybe it belongs in the temptations category) I believe that if you get a decent or high end calibration it can be considered value for money. This product should be attractive to people living in apartments, semi d's or who want loud late night listening without upsetting the family. I love mine.