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Frequently Asked Questions


What Can a Professional Custom Installer do for You?
10 Smart Consumer Electronic Tips for the Home Environment
Acoustical Considerations


What Can a Professional Custom Installer do for You?

The custom installer can offer:
The sights, sounds and excitement of the movies - in the comfort of your own home theater.
The pleasures and convenience of high quality audio and video in every room, controlled from any room.
The safety and peace of mind of a state-of-the-art home security system.
Telephone and intercom communications throughout your home and grounds.
Automated control of lighting, draperies, doors, cabinets, at the touch of a button.

A professional custom installation makes it all possible.


10 Smart Consumer Electronic Tips for the Home Environment

"Who should I talk to about creating a home theatre?"
"Should I throw away that VCR?"

If you are bewildered about the consumer electronics age, Custom Electronic Design and Installation Association (CEDIA) offers 10 Smart Consumer Electronic Tips for your home environment.
The 10 Smart Consumer Electronic Tips provide you with a concise and informative list of helpful hints to assist you in making smart decisions when purchasing home consumer electronics.
The 10 Smart Consumer Electronics Tips is a collaborative effort developed by members of CEDIA. Members of CEDIA are knowledgeable and talented professionals representing all facets of the industry from designers/installers to manufacturers and sales representatives.
CEDIA developed this list of recommendations after many hours of collaboration between our members. Our goal for developing this list was to take an active role in providing assistance to the consumer. These tips cover four areas: innovation, investments, integration and ease of use.
Although this advice is geared toward the consumer, it is also beneficial to the custom electronics professional. When building or remodeling, the designer or builder may use this list as a reference for making recommendations on home integration to their customer.

Here is the list:

  1. Wire for everything now – If you are building or remodeling your home, wire it with a plan for future needs. While no one can guarantee what the future will look like, CEDIA Professionals make it their business to stay current to offer good advice about technologies that are on the horizon. Best of all they can help you sort out the hype from the reality.
  2. Plan for HDTV now – High Definition TV is the new digital standard for enhanced picture quality for TV broadcasting. If you're buying a new TV or video projector, make sure you'll be able to enjoy the incredible sound and pictures that are part of HDTV.
  3. Insist on integrated systems – As you buy new electronic components, make sure you shop for equipment that can be hooked up together and operated with one, easy to use control system.
  4. Don’t buy yesterday’s products (often what is in stock) – Many stores purchase large orders of all equipment and sell it at discounted rates. Shop with a dealer that only provides you with new equipment and technologies.
  5. Consider integrating lighting control with your home electronics system — Lighting sets the mood for home theater, entertaining, or just a quiet night at home. You can control your home lighting from the same remote that you use to control your theater or music system.
  6. Think with your wallet, but lead with your head - Quality and long-term dependability are the most cost effective attributes that you can build into a home.
  7. Buy an experience, not a box – Find a dealer that allows you to test drive the entire system or at least experience the thrill of a high performance system. Few people have the time to research and evaluate all the hardware choices. It's smarter to focus on the end result and make your choices based upon overall performance and value.
  8. Don't think you have to put up with hard to use, multiple remote controls – Easy to use, all-in-one remote controls are available for any system. You can even have them custom programmed so they make perfect sense to you.
  9. Consult a professional - Designing and installing reliable, easy to use systems that add real quality to your lifestyle is the goal of CEDIA professionals. Check to see if the company you're considering has CEDIA Certified Professional Designers and Installers on staff.
  10. Increase your service expectations - Your home electronics system is a big investment. CEDIA professionals will provide you with extensive options, comprehensive designs, complete installation and especially, in-home service for your systems.

Custom Electronic Design and Installation Association [CEDIA]... professionals ensuring your dollars are invested well while focusing on the design, integration and installation.


Acoustical Considerations

As audio technology becomes more sophisticated and more prevalent throughout homes, consumers are becoming increasingly aware of the need for excellent sound quality and sound privacy. Manufacturers of audio equipment from compact disc players to loudspeakers constantly strive to provide their end-users with the highest sonic fidelity with minimal distortion of the original recorded program. Yet how many owners of this sophisticated audio equipment realize that the last device in the audio chain is not the loudspeaker, but the room in which they are listening to the material?

The listening room will severely affect the final quality of sound that is heard from an audio system by either absorbing, reflecting, diffusing (scattering) or transmitting sound waves that impact its boundaries. Just as you may choose a color of paint on a wall to achieve an aesthetic look or select a light fixture to provide the appropriate amount and coverage of light, one should also ensure that the surface materials on the walls, ceilings and floors of an audio listening room are carefully chosen to achieve a balanced sound level in the room throughout the entire frequency range of human hearing.

Because the knowledge-base of acoustics is so limited in the architectural industry, audio-listening rooms and home theaters are often built with no real attention given to the natural sound of the room. We have even heard of times where the audio/video designer will even suggest to the architect or homeowner that they don't need to spend any money or effort on acoustical treatments, since they can simply compensate for the bad room acoustics with equalization. As will be shown in a future article, this approach is only marginally effective since it is essentially creating a deficient sound to compensate for a deficient room.

Yet where does a homeowner or a designer go to achieve a room design that will enhance the state-of-the-art audio system in every way possible without adding distortion to the sound that reaches the listeners' ears?

Acoustical consultants have been assisting architects and building owners for decades in the design of performing arts theaters, concert halls, recording studios and many other types of commercial, industrial and, more recently, residential spaces. With the advent of multi-media theaters and critical audio listening rooms in residences, it has never been more appropriate to engage the services of a qualified acoustical consultant to, not only work with the home designers to achieve great natural-sounding spaces, but to also contain the tremendous levels of sound and vibration produced by modern full-surround audio systems. This is often very important with families where perhaps the children want to invite their friends over to watch the latest action movie in the home theater while the parents want to relax upstairs or do work in a home office.

The best acoustical consultants are not in the business of selling products, but instead have objectively evaluated all products and construction methods and are able to specify the right combination that is appropriate for each project.

Audio Visual Design has it's own on board full time acoustical consultants along with having affiliations with the top east coast acoustical dealers. Having professional musicians, and chief studio recording engineers on hands to lend their knowledge and discriminating ear. Audio Visual Design can provide you with the most optimal acoustic room possible.



NC (Noise Criteria) (Whole Number >0. e.g., NC-25)

The NC level of a room is a number rating of the noise level of an interior space. The NC number is associated with a series of sound energy level-versus-frequency curves known as Noise Criterion curves. For new construction, a Noise Criteria is established based on the room's type and its intended function, and is used as a goal in the design of sound isolation construction and the attenuation of mechanical systems noise. To determine the NC rating of an existing space, octave-band frequency noise levels are measured and plotted against the series of NC curve spectra.

In a Home Theater or other similar space, it is important to have a very low background noise, or NC level, since this directly affects the dynamic range of the audio. If your noise level is high, you will have to turn up your system to hear the quietest passages. Unfortunately, this will also make your loudest passages even louder, which may be uncomfortable to your ears and require additional amplifier power and sound isolation from other rooms.

STC (Sound Transmission Class) (Whole number >0. e.g., STC-56)

The STC is a single number method of rating the sound isolation performance of a wall, floor, ceiling, door or window. Like the NC, the STC number actually refers to an entire spectrum sound level, in this case, divided into one-third octave band values. The higher the STC number, the better a partition isolates sound overall.

STC numbers should be used only as a broad comparison between two or more partitions. One reason for this is because the same sound source played through an STC 50 drywall partition and an STC 50 concrete block partition will sound quite different on the other side because of the way each type of wall isolates different frequencies of sound. The one-third octave band levels (known as Transmission Loss (TL)) are essentially the difference in level between a sound measured on the same side of a partition and the levels measured on the opposite side. For a thorough sound isolation design, the TL numbers should be evaluated based on the frequency and level content of the source noise and the specific NC level required in an adjacent space.

NRC (Noise Reduction Coefficient)
0.00 <= NRC <=1.00* e.g., NRC = 0.85)

The NRC value is a single number method of rating the sound absospecific frequency band if it reflects virtually all sound at that band. Concrete and brick are examples of materials with low sound absorption coefficients at all frequencies. Materials such as thick (4" or greater) fiberglass insulation and some foams have high absorption coefficients near 1.00 at most frequencies. The NRC rating is defined as the arithmetic average of the material's measured sound absorption coefficients at the 250Hz, 500Hz, 1000Hz and 2000 Hz octave bands. These frequency bands represent the range of sound most associated with speech.

If the material is required to absorb very low or high frequencies of sound, the individual sound absorption coefficients should be used for comparison, rather than the NRC value. This is very important to note in a Home Theater where the audio contains a lot of low-frequency sound energy. You may be tempted to use an acoustical wall panel or ceiling tile with a high-NRC rating throughout your Theater space. However, since the NRC doesn't tell you how or if the material absorbs low-end sound, you could end up with a very bass-heavy room unless you try to achieve similar amounts of sound absorption at all frequencies of interest.

* Note that data published for some acoustical materials may show absorption coefficients greater than 1.00 at one or more frequencies. This is because the effective absorbing surface area in a thick or shaped material is greater than the material's face area used to determine the absorption coefficient.



dead room: A room containing a large amount of sound-absorbing material.

diffusion material is a material in a room that causes sound waves impacting on its surface to be scattered in multiple directions. Examples of diffusive shapes include convex or splayed walls and ceilings, coffers, columns, pilasters and very ornate architectural surfaces. Hard furniture and sound-absorbing panels spaced at intervals along a reflective boundary surface will also add some diffusion to a room.

flanking path: a path between adjacent spaces other than through a common partition that sound or vibration is transferred

flutter echo: a rapid series of reflections usually created when a sound is played between two hard and parallel room surfaces. Flutter echo is often perceived as a "buzzing" or "ringing" sound and can be detrimental to the clarity or intelligibility of a sound. Simple solutions for eliminating this occurrence include: creating an offsetting angle of at least 5° between the two surfaces, adding sound absorptive materials to one or both surfaces or adding diffusive shaping to the surfaces.

live room: a room containing very little sound absorbing materials.

room modes: Fluctuations in the energy level of sound dependent on frequency, source position and listener position in the room. Modes are produced at frequencies relative to the room's primary dimensions and are caused by the reinforcement and cancellation of multiple sound waves. They are often referred to as standing waves, since a sound produced at the fundamental modal frequency appears to be stagnant in the peak energy position.

reverberation time: The amount of time at a specific frequency that a sound in an enclosed space takes to decrease 60 decibels (basically to inaudibility) in level after the source sound has stopped. The reverberation time gives a listener the sense of the size, liveness and warmth of a room. Reverberation time increases proportionally with the cubic volume of the room and decreases proportionally with the quantity of sound-absorbing surfaces in the room. So, unless a Home Theater is unusually large (which it shouldn't be) or highly-reflective (which it shouldn't be) there will be very little sound buildup or decay. Thus, reverberation time is not a very useful measure for the acoustic quality of a Home Theater.

source and receiving room: terms used in sound and vibration isolation analysis to designate the room containing the sound or vibration producing source (source room) and an adjacent (receiving) room requiring that the source noise be attenuated by the intervening partitions to a specified noise level.



M&M #1: Fiberglass or foam placed on a wall will prevent sound from going through it.
Reality #1: These materials only absorb sound and do not provide a barrier to it. Heavier building materials and resilient attachments to structure are the best methods for isolating sound.

M&M #2: Carpet on a floor will reduce sound transmission to a room below.
Reality #2: Carpet is a sound absorbing material mainly at high frequencies, and has very little airborne sound isolation properties. Carpet does, however, reduce the amount of impact sound from footfall or things dropped that is transmitted to the space below.

M&M #3: Egg cartons on the wall improve the sound of the space.
Reality #3: While egg cartons do have some sound-absorbing and diffusing properties, they are concentrated in a relatively narrow frequency band and do not positively effect the quality of speech or music to any significant degree. They also have negligible sound isolation properties.

M&M #4: Adding insulation to a sheetrock wall will keep all sound from going through it.
Reality #4: Insulation between stud cavities in a sheetrock partition does improve the sound isolation value of a partition and should be used whenever possible. The improvement, however, is too small to bring about an appreciable difference in the degree of isolation, and the insulation should only be thought of as a partial solution to upgrading the isolation of a partition.

Reality #5: This word is the catch-all phrase used by many for improving anything that has to do with acoustics. "Soundproofing" implies building a room that will keep all possible sounds outside the space from transferring in, and all sounds generated in the space from transferring out. Building construction can be designed to attenuate a fixed degree of sound, but cannot theoretically prevent all possible sounds from passing through the boundaries of the room, except in extremely rare (and expensive!) situations. Better terminology to use when describing a client's acoustical needs may perhaps be "Noise Reduction" (for sound isolation) and "Sound Enhancement" (for room acoustics).


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