Over the years, we have received numerous questions
about setting up the Zone 2 functions on receivers. Zone 2 refers to a
stereo line-level output on the back of the receiver that can be used to
drive a power amplifier in a second room so you can have background music at
a party, for example.
Since Zone 2 is most
often line-level (about 1 Volt or so), you need to have an additional power
amplifier either right next to the receiver, or in the next room where you
have the Zone 2 speakers.
For Zone 2 operation, the main receiver acts as a
volume control and source selector. Therefore, it is not necessary to waste
money on an integrated amplifier that has a lot of features you would never
We looked around for basic two-channel amplifiers
that might be used in Zone 2 situations. The AudioSource AMP-100 is our
first selection for this purpose. In fact, the AMP-100 is designed
specifically for custom install projects, and has the basic things you would
need for use in Zone 2, namely, auto-on, auto-switching for two inputs, and
two sets of speaker outputs (Speaker Set A and Speaker Set B).
The AMP-100 outputs 50 watts per channel into 8
Ohms. This is perfect for Zone 2 and background music at parties, or for
just having dinner by yourselves.
The front panel of the amplifier has an on/off
switch, buttons for selecting Speaker Set A or B, and a volume control for
The rear panel has RCA jacks for two sets of stereo
inputs, as well as a line-out for Input Set 2. This lets you forward the
signal for Input 2 to another room (Zone 3) if you like. In other words, you
could then have the receiver send CD music to the den or bedroom, through
the Input 2 line-out on the AMP-100. Of course, you would need an additional
power amplifier in Zone 3.
The back panel also has a slider switch for bridging
the AMP-100, but I don't think that is of real use in a Zone 2 situation.
There is a slider for setting the AMP-100 to Manual-On or Auto-On. For Zone
2, you would probably want to set it to Auto-On so that it turns on when you
activate the Zone 2 operation from the main receiver.
There are two sets of speaker binding posts for each
channel, one set for Speaker Set A and one set for Speaker Set B. Thus, you
can activate either set. For example, you could have one set in the dining
room and another in the kitchen. Both sets of speakers can be active at the
The AMP-100 AC power cord is two-conductor, so it is
unlikely that you will encounter ground loops with typical two-conductor
power cord receivers.
The on-board volume controls make it easy to fine
tune the volume in Zone 2 rather than having to go back to the main
Auto switching for two inputs means you can use the
AMP-100 to drive a second source that is not part of the receiver. For
example, the second input could be used with the line-out from a TV in the
dining room, when you want to have more volume. The auto-switching gives
Input 1 priority, so when it is turned off, and Input 2 is active, the
amplifier switches over to Input 2.
I tested the AMP-100 using stereo outputs from
several of my sources as well as just connecting them to a CD player
The AMP-100 is not designed to compete with high
powered, expensive two-channel amplifiers. Nevertheless, I was pleasantly
surprised at how good it does sound. Part of this is due to the fact that
the AMP-100 is made overseas at manufacturing facilities that produce
thousands of amplifiers for various OEM contracts all over the world. So,
you are getting a lot for your money.
With only 50 watts per channel, the AMP-100 runs out
of steam as the volume is cranked, but that is not its purpose. At modest
volume, actually a little higher than one might set it for background music,
the AudioSource performed well, giving plenty of detail, tight bass, and no
background hum or noise. If you want to play "Jurassic Lunch" with the 8 Hz
footsteps, into low impedance, low sensitivity speakers, forget it. But for
Beethoven, at coffee and dessert SPLs, it's very nice. If you want more
power in Zone 2, say for dancing, you might go with the
The built-in volume controls are handy for
situations where one speaker might be farther away from the dinner table
than the other, so you can turn up the volume on the farther distance
The AudioSource AMP-100 is a nicely featured, good
performing, two-channel amplifier that is perfect for Zone 2 operation. At
its price (I saw it for $103 at an Internet store), you simply cannot go wrong.
- John E. Johnson, Jr. -