Pre-Amplifiers
Pre-Amplifiers are your Home Audio control center
A pre-amplifier is the stage of a receiver or separate component responsible for switching between components in your audio system. Most of today's Home Theater receivers with integrated pre-amp features are also capable of providing switching for your video components to your TV as well. The switching aspect of the receiver or separate pre-amplifier is what makes it the control center of your whole system.
Using a remote control, the pre-amp can switch from the CD player to the DVD player and instantly provide the video from the DVD player to the TV. A popular feature with today's Home Theater receivers is the universal remote control. Many remotes that come stock with the more elaborate Home Theater receivers garner as much attention in hi-fi reviews as the receivers themselves. Marantz is known for their LCD touch screen remotes that work well but eat batteries like candy. Arcam's AVR receivers have a really sharp looking indigo blue backlight remote that never fails to please.
The universal functionality of these receiver's remotes really adds to the pre-amp's job as control center. Most users are quickly accustomed to turning on the TV, the Digital Cable Box and turning off the DVD player, and then switching channels on the cable box, all from the same remote. Most of these functions are performed by communication between the pre-amp stage of the receiver and its included universal remote control.
The back of the receiver or pre-amp is where you'll want to look to get the at-a-glance run down of the receiver's features. This is where you'll see what formats the hardware is compatible with and what level of flexibility you can expect when working between these formats. You can see how many available optical or coax digital inputs are available. Does the receiver have any special connection options like Firewire, RS 232 or even RJ45? If the receiver or pre-amp is equipped with HDMI inputs, you'll find out from a quick glance at the back. Most of the video connections you'll find on today's receivers are S-Video and Composite and you can switch between them.
It's unlikely you'll find component, HDMI or DVI in/out switching available on any but the most expensive models. This is partly because presently the future of these formats is a little uncertain. The costs associated with a misstep in design could prove devastating to any product line. Soon you'll see more receivers with HDMI switching capability priced for the masses, as it seems to be the industry standard for Home Theater. But if you're using HDTV, for the time being you'll have to perform switching from within the TV itself, which is really no problem, if you've programmed your receiver's universal remote to control the TV.