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Psychoacoustics
We hear with our brain
Our ears are the body's transducers for audio input. No hearing takes place in our ears or the ear canal. Hearing takes place in our brain. Our brain translates the vibrations through a series of nerves and processes them into audio information.
The way that the brain processes this information is only somewhat understood. However, there are many phenomena that occur that can only be explained through psychoacoustics.
Here is an experiment that you can try. Start humming. While humming, place your hands over your ears. Notice that the sound now appears to come directly from the center of your head. If we didn't have our outer ears, all sound would seem to come from the inside of our head.
The reason is that sound that comes from behind us sounds different than the sound the comes from our front. The outer ear creates an obstacle so that sounds coming from the back sound different than sound coming from the front. Having two ears, our brain is able to localize where sound comes from.
Without going into detail how the process works, the brain is able to tell where sounds emanate from by comparing sound that is out of phase with sound that is in phase. Basically, the brain is able to process input from two ears based on whether the sound arrives in phase, out of phase and if it comes from the front and rear and how much delay is there from the sound reaching one ear canal versus another.
The idea behind stereo is that if we can create true three dimensional sound with only two ears, two speakers should be able to do the same thing. There are all sorts of reasons why this isn't possible (although it is possible to do this using headphones and something called biphonic recording).
Some loudspeakers when positioned properly are able to create a phantom channel that is between the loudspeakers. To some degree, the loudspeakers can create sounds that appear to come from several locations in between and outside the loudspeakers.
In order for loudspeakers to create three dimensional sound, the loudspeaker must properly handle phase and time domain information. The reason is the the brain relies on this time and phase information to accurately recreate the correct location where the instruments should be.
This phenomena requires that the CD or music source is properly recorded. Many pop CDs are mixes of individuals and not the recording of an actual live event.
The Brain plays tricks
One of the problems evaluating loudspeakers is that the brain has very poor auditory memory. Comparisons between one loudspeaker must be made in near real time or it is impossible to evaluate a loudspeaker.
This means that it is impossible to shop from one store to another to compare loudspeakers unless the evaluator makes judgments about the speaker at the time of listening and then compares the evaluations.
The lack of auditory memory is the reasons why some people can become convinced certain actions or products can improve the quality of the reproduction. I have tested many ideas that were suppose to improve the sound of my CDs. These include marking the edges with green inks, putting rings on CDs and using a CD Clarifier. I am not certain which or if any of these work because it is nearly impossible to do A/B comparisons of such actions.
So profound are some of these claims, engineers and people that should know better become convinced in the value of many of these products. Having said this, this author wants to point out that audiophiles have often been correct trusting their ears. Audiophiles uncovered the problem of jitter in CD players before any tests were available to measure this phenomena. Audiophiles uncovered the problem using negative feedback in solid-state devices. Audiophiles also insisted that certain equipment that measured nearly perfectly had problems. Many engineers were unable to explain what Audiophiles were hearing. However, we now know that what they heard was in fact true.
Because audiophiles have had a very good track record uncovering faults and helping engineers improve the audio quality of products, it is difficult for me to dismiss some ideas that sound ridiculous from a technical standpoint. I have seen audiophiles that are very sensitive to reversed channels and reversed phase. I have seen audiophiles that can tell whether a CD is original or replicated bit by bit by a computer. Therefore it is fair to say that these individuals have increased the processing power in their brain to determine differences in sound that would escape most people.
The audio consumer has to somehow balance what they understand against what they are told because not everyone selling audio products are motivated to advance the quality of audio. There are many products that are completely useless.
In the audiophile world, the term "psycoacoustics" is used to refer to phenomena that improves sound but can not be explained with traditional science.
What does all this have to do with nOrh
I get a lot of advice how I can improve the quality of sound. I had someone tell me to put coins on the loudspeaker. I hear advice on the directionality of wire and how using certain types of stones and crystals will improve the sound. I have tried to follow a policy of healthy skepticism and practicality building loudspeakers. I don't believe anything until I try it out for myself.
We have found that there are many things we can do to improve the quality of the sound. For example, we now use silver wire for our wiring. We believe this does have a very positive impact on the sound. We even use silver wiring in our crossover. There is a slight increase in cost doing this. However, it isn't as much an increase in cost as other manufacturers might have you believe.
I encourage our consumer to test out ideas and products. If you feel that there is an improvement using a certain cable or different feet, let us know. We will pass this information on.
I have tried to build the best product that can possibly be built at this price.
Conclusion
We have found that the more clarity we can provide from the loudspeaker, the easier it is for the brain to recreate an accurate representation of the live music experience from the recorded information. We believe that the nOrh loudspeakers will create a very credible representation of a musical event. We believe that the reflections that take place in most box speakers, blur the time and phase information the brain needs to process the accurate information. I have had some listeners tell me the the image created by two nOrh loudspeakers is almost eerie. One person was adjusting his CD player when he was surprised to find that it sounded like he was standing inside the drums. He described it like he was walking through a ghost band.
I often have people ask us if we only have two speakers playing. They believe there must be other speakers creating the 3D illusion.