Why Equalize?


What Equalization does:


You have spent a lot of money for your home theater system and have purchased excellent components. You have had them installed in your home theater room, yet you feel you don't have the sound quality that you expected. Why? In all likelihood the problem is the room itself. Like fingerprints, each room is different. No two rooms are exactly alike. All rooms have their own characteristics. There are reflections caused by sound bouncing off of walls, ceilings, and floors. There are doors and windows which act as reflectors, and furniture that will absorb and reflect sound. All of these effects color the sound. A good example of room problems is the feedback effect that we have all experienced in a listening hall when the microphone was being set up. You heard the whistling of the room resonating before the microphone was turned down. The same effect occurs in your listening room. What you want to do is to listen to the movies and have them sound to you the way the maker of the movie intended. The following paragraphs give you some of the highlights showing what can be done to fix your listening experience.

The problem is the room.

There are many things that effect sound in any room including: The hardness of the walls, the angle of the sound when it strikes the walls, the pitch, the distance from the loudspeaker, the location of the listener, and the interaction of all of these sound waves. In addition to reflections, there are pitch selective absorbers like drapes, carpets and furniture which also have their effect on what is heard. Many of these can be controlled to some degree or another by treating the walls, ceilings, floors etc. but in some cases this is difficult or impossible. Wall reflections can be controlled, to some degree, by hanging absorbers and dispersers, floors can be controlled, to some degree, by carpets, ceilings by hanging acoustic absorbers. Windows can also be treated by adding drapes. All of these treatments can be used to improve sound quality, but may not allow decorating the room to your taste. Doing this treatment properly is an expensive process requiring knowledgeable people using expensive test equipment, and still won't really be right, just better.

How can the room be fixed?

In the previous paragraph we indicated some things that could be done to improve the performance of the listening room. Fortunately, in addition to the architectural treatments outlined above, there are also electronic systems that can offer very improved audio performance to fix many if not all of these room problems. These electronic systems are called equalizers. Equalizers have been used for professional applications for over 50 years. All high quality movie installations use equalizers to fix problems associated with the theater acoustics. Almost all professional sound installations use equalizers to fix acoustic problems. In the same manner as professional systems, equalizers can be used to make significant improvements in the performance of your home theater by installing suitable equipment. The word suitable is important because there are several types of equalizers manufactured, which operate differently.

Equalization what is it?

Equalization is the process of changing the strength of the sound in bands (slices) of audio frequencies so they are equal; thus the name. There are two fundamental types of equalizers Graphic and Parametric. Graphic equalizers break up the sound into a number of fixed bands. Depending on the system this can be as few as two or three or as many as 30 or more. Parametric equalizers have variable frequency bands, normally one, two or three, and try to correct for the worst offenders within the frequency range. Both systems have their place in audio systems depending on the problem being addressed. In general parametric equalizers cost less than graphic. This is because they need less hardware but are also much more limited in the amount of correction they can perform. Graphic equalizers, though more expensive, have much more capability to correct for numerous issues.

Why you want the Neptune Audio EQ 701

The Neptune Audio EQ 701 provides the best sound quality available because it is designed specifically for the high end home theater, using the best components money can buy. It is the only equalizer on the market that does automatic room correction for an entire 7.1 channel home theater installation in a single unit. It uses the latest state of the art in digital signal processing.

The EQ 701 does room equalization using a thirty band graphic equalizer system. It corrects the entire frequency range by splitting it into thirty 1/3 octave bands per channel, plus twenty more for the subwoofer channel for a total of 230 bands! Then correcting for audio imbalances between these bands.

Powerful yet simple

The Neptune audio EQ 701 system has a built in function to perform automatic room equalization. The Processor in the unit generates a series of test signals. These test signals are directed to each of the loudspeakers one at a time. A calibrated microphone (provided with each unit) listens to the received sound and sends that signal back to the processor. The processor then compensates for the room's acoustic effects by adding or subtracting signal and making the room response uniform, and you can do it by yourself!

In addition to the automatic EQ function there are manual controls available to modify the sound for individual preferences.

To perform the same functions with competing products, you would have to provide specialized test and measurement equipment along with hours of a skilled technician to set up these units. This requires significant skill from the installer. It is costly and still wouldn't give you the quality that can be provided with the EQ701.