How important is it for you to attain a holographic image?

We only have two ears, not 5 or 7, and yet, if you close your eyes and have a friend walk around you while speaking, you have no problem determining where he is, yes?  That's because you are hearing not only his voice directly, you are also hearing the reflections of his voice bouncing off the walls around you. You are hearing him AND the room around you. You hear in 3 dimensions.  You are hearing the ambience of the room. Whether you are listening to a studio album or a recording of a live performance, that ambience gets recorded, unless of course, it is done in an anechoic chamber. An ambient loop, or Hafler loop, as it is sometimes called, is what you need to reproduce the ambience that is recorded on every DVD, CD and vinyl record you own.  Back in the 60's, David Hafler realized this, and invented the Dynaco QD-1 Quadapter when he was at Dynaco. It is designed to extract this ambience. All you need is two more speakers in the rear, with the same signal from the front, going through the QD-1, and then out to the rear speakers. If the front signal is absolutely identical on both sides, the rear speakers won't make a sound, The more difference in the front, the more the rear speakers will sound. It is as close to how we normally hear as one can get, and produces a wonderful 3 dimensional image. I've been listening to an ambient loop system for 45 years. If you're familiar with the movie 'Inception', you should hear the village scene on my system. It will blow you away. I should note that with movies like 'Inception', you have a choice of listening in 5-1 or just stereo. I always choose stereo, as I do not have or want a 5-1 system. If anyone wants to further discuss my system, or tell me that I'm full of BS, you can email me at prvk@earthlink.net. Be sure to put something in the subject line that I'll recognize, as I have a pretty aggressive anti-spam program.

Peterprvk@earthlink.net

Stereo sound is analogous to 3D movies or even stereo optics for viewing maps that have been developed from aerial photographs of the same geographical area taken from different angles. There is some similarly to those 3D computer generated images (stereograms) in that some skill or learning is required to be able view those images in the deep three dimensionality they can provide. Ideally, soundstage and imaging should be natural and should duplicate to a large extent what the experience would be like in person, with two ears. The experience should be natural, transparent and convincing, not phony.

rvpiano,

If a singer is panned to the middle of a stereo mix, or if you are listening to a mono mix, virtually any half decent pair of speakers will produce the effect you just mentioned of the singer seeming to be in the middle of the speakers, hanging in space.

This happens pretty much be default given the stereo imaging process.

- It always happens in a typical stereo set up with a centralized listener.
- It's always artificial.
- There are common existing audiophile terms to describe the effect."Soundstaging" (in general, the apparent scale and dimensionality of the soundspace seemingly created by the speakers) and "imaging" (in general: the localization if individual sound sources - for mono, always localized between the speakers).

Therefore, I don't see what new distinction you wish to make with "holographic" as if it were to refer to something distinct from the normal terms "imaging" or "soundstaging."

Anyone else know what rvpiano is trying to describe if it isn't just plain old imaging/soundstaging that virtually all of us can xperience from our system?


(I can't imagine anyone here has a pair of speaker so awful that, when situated in the stereo configuration, would not produce the singer-in-space-between-the-speakers effect).

Peterprvk, Re the Hafler loop - I agree that this can have  a very pleasant encompassing effect. I believe that it really is not much more than reproducing out of phase sounds  thru separate speakers using the same amp as used in the front speakers but you need a separate attenuator  to get the right volume level (came in Hafler's box). Its simple and as far as I'm concerned, while not as sophisticated as most multichannel systems, it is effective and you don't have nearly the set up issues. For other reasons I chose to use only 2 channel systems, mainly because I'm not inclined to fiddle with placement and volume issues every time I put on a recording and more inclined to just listen to the music not the effects.

Interestingly Carver had a shot at holography which I tried out back in the day. The first thing I noticed, and it blew me away, was in a cut when the audience applauded a performance it placed you in the audience, as opposed to hearing all of the applause in front you. But it really became more of a distraction than a benign additive and I lost interest. This black box I believe was doing nothing much more than playing with phase issues. 

One of the problems with max'ing out the soundstaging potential is when a recording is made, which includes all of the ambiance sounds in the recording environment, is that these sounds when reproduced thru your system can be in conflict (confused) by the ambiance in your room. For example if you have a recording with lots of ambiance and you play it in a bright room you are hearing neither of them any where near accurately. (Interestingly though, if you played a recording with all of the recording ambiance encoded and played it back in a 'dead acoustic' I think most folks would find it dead/dull as well. We have become quite adjusted, I think, to hearing the recording's ambiance when it is superimposed on the room acoustic  (we know our rooms that well). 

Anyway, that's all I know. :-)

Let's segway into a discussion of binaural recording and binaural sound reproduction.