The good news is that home theater equipment is better than ever, and more affordable to boot. In addition, there is much help available, on the Internet or from one of the many qualified custom installation firms in most areas.

Home Theater Design - Part 6

Steve Faber | Home Theater Design and Automation

Home Theater Design and Construction - Part 6
by Steve Faber
 Home Theater Design and Automation

The good news is that home theater equipment is better than ever, and more affordable to boot. In addition, there is much help available, on the Internet or from one of the many qualified custom installation firms in most areas.


Click here for Part 1
Design Considerations
Click here for Part 2
Click here for Part 3
Speaker Placement
Click here for Part 4
Room Acoustics and Lighting Design
Click here for Part 5
Time To Start Shopping 

In the last installment, we'd started to look at how to determine what components to select for your new home theater. The decision process can be roughly broken down into four criteria:

Performance - Your component choices need to be able to deliver the home theater experience you're looking for.

Features - Your system needs to be able to do everything you want it to.

Ergonomics - Your system should be easy to understand and operate as you'd like it to. It also needs to fit in the alloted location.

Budget - You need to be able to actually buy it. It's this last item that makes home theater component selection a challenge. Almost anybody could get a fantastic home theater if money were no object.

There are some things to look for when selecting components that can impact the synergy of your system as a whole, yet have no real impact on how well it performs. A key one of these is discrete infrared (IR) control codes. IR is what most remotes use to send their control signals. The IR control codes are issued by the component's remote control and go on a beam of invisible IR to tell the device what to do. A discrete control code commands the system to go directly to a single state. The two most common types of discrete commands you'll need are for power and input selection. Many components don't have discrete codes for these functions on their remote control. You'll be stuck with a single "power", "input", or "TV/Video" button for these functions instead. The absence of discrete codes can make it very difficult to automate your system using control macros for easy, "one touch" operation.

A discrete code, on the other hand, will allow the system to be put directly into a specific state, such as "power on", "DVD", or "component video 2" for example. The easiest way to tell if your components have these codes is to simply look at the remote control for each piece of gear. If it has a different button for "power on" and "power off" and separate buttons for each input, rejoice!!! Your component has discrete codes. Some manufacturers actually have discrete codes available for their components, even if they fail to include the buttons for them on the remote that is supplied with the component. These codes can be found on the Internet, either at the manufacturer's website or at one of several different sites dedicated to remote controls.

Sometimes, however, discrete remote codes just don't exist for your particular component. In this case, you can still construct an effective, easy to use remote control interface. You just need to go to greater lengths to get there. You'll need to use a more advanced remote control system, such as those from Crestron, AMX or RTI, that will let you monitor the power status of a particular component. For a "power on" macro for example, you must check to determine the power state of the component in question. You can then determine weather or not it's appropriate to send a power toggle command that will reverse the power state of the component. If you have an advanced control system already, this is great. If not, it's often better to just pick a different component, rather than incur the expense of the additional remote, control processor, programming and sensing equipment.

Many components are now available with serial control (RS-232), Ethernet control, or both. These let you control your component using one of the aforementioned control systems such as Crestron, or from a PC. In many cases, the command set for the serial control will include discrete commands when the IR command set does not. Sometimes, you need both! There was a case a few years ago where a certain manufacturer's flat panel TV had discrete, IR codes for everything except power on. For that, you needed RS-232 control. Very Frustrating! So, if at all possible, choose components that have discrete remote control codes. It will make yours, or your installer's, life so much easier.

You may also benefit from using a receiver or surround processor with a second zone output. A second zone is like having two separate, virtual systems from one component. This lets you share your source components between your theater system and your house audio system. You can have completely independent operation of the two systems, yet all your source components plug into your receiver or surround receiver just they normally would. It lets you turn on your theater system for example, without turning on the speakers elsewhere in your home and disturbing others. You can also listen to different sources simultaneously in each zone. You could, for example, be enjoying a DVD in the family or media room, while listening to music from a CD or music server in the second zone.

Many receivers and surround preamp/processors now have two zone capability. A 7.1 channel receiver will usually give you the option of running your surround sound system in a 5.1 configuration. You can then use the internal amplifiers normally reserved for the rear speakers to run the speakers in the second zone. If your theater is configured for 7.1 operation, you must use a separate amplifier to power the speakers in the second zone.

Many people would like to keep their theater components hidden behind cabinet doors or in an adjacent room. This is possible, you just need to use an IR repeater or use a remote that has the option for radio frequency (RF) operation. An IR repeater simply has an IR receiver to receive the IR commands from your remote control. This unobtrusive device is placed by the TV or projection screen. It changes the commands from IR to an electrical signal. They are then sent over wires to the location of your components, where they are sent to small IR emitters that convert the electrical signals back to IR to control your components. Be aware that IR repeater systems may require special parts to be used with plasma displays, in a room with fluorescent lights, or in bright sunlight.

If you use a remote with RF transmission, the commands are sent from the remote using radio frequency signals to a base station that is located with the theater components. The base station then sends the IR signals to control your theater components. The RF system has an advantage in that the remote doesn't have to be pointed at any specific target. This can be helpful when the remote is programmed with long macros. For example, some "start show" types of macros will lower the screen, turn on all the theater components in the proper sequence, switch everything to the desired input, lower the blinds, and lower the lights. These long macros can sometimes take 15-30 seconds to fully execute. It's tough to keep the remote pointing at the IR target for that length of time.

RF remotes are not without their troubles however. They are subject to RF interference. This interference can cause fickle operation, and some things may not operate reliably. To counter this type of problem, and ensure reliability, some of the more expensive remotes, like those from Crestron, use digital spread spectrum technology for the RF link. Now widely used on cordless telephones to ensure reliable and secure operation, this technology was first developed for the military for the same reasons. The use of DSS technology is one reason upper end control products tend to be significantly more expensive.

It can be tough to get all the performance and features you want while making sure all your components work well together. The good news is that home theater equipment is better than ever, and more affordable to boot. In addition, there is much help available, on the Internet or from one of the many qualified custom installation firms in most areas.

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