Page 1
1 THANK YOU!
Congratulations and Thank You for Choosing Parasound
Your new Parasound Halo Series A 21 power amplifier presents the latest advancements
in amplifier technology. The A 21 is built to the strict quality and performance standards
set by Parasound. Were proud to offer you this exceptional audio component that will
bring you many years of enjoyment and dependability.
Here at Parasound, we design our products to perform at a higher level of flexibility
and sonic performance than you may have expected. We encourage you to read
this entire manual to learn all the features and capabilities of your new Halo Series
A 21 Amplifier.
If youre eager to get up and running right away, simply follow the basic step-by-step
instructions to connect and operate the A 21. If you want to learn about some of the
technical and design aspects of your A 21, refer to the Technically Speaking and
Parasound A 21 Design Overview sections in the back of the manual. If you run into
difficulties, the
Troubleshooting Guide should help you quickly remedy the problem.
We appreciate you taking the time to read these instructions and thank you for
selecting Parasound for your listening pleasure.
The Parasound Staff
Unpacking Your A 21
Unpack your A 21 from the shipping carton, remove the enclosed rack mounts, AC
power cord, and the control wire with 2.5 mm sub-mini plugs on each end. (This is
the trigger connection wire). While you are unpacking your new amplifier, inspect
it thoroughly for possible shipping damage. If you see any, contact your Parasound
dealer right away. Be sure to save and store both the inner and outer cartons and the
packing inserts for possible future transport. To save room for storage, you can cut the
seams on the bottom of the cartons and flatten them.
Keeping Records for Future Reference
Record the serial number located on the bottom of your A 21 in the space below. Also
note your Parasound Dealers name and phone number. We recommend that you keep
your purchase receipt with this manual and store them both in a safe place. You may
need to refer to this information sometime in the future.
Parasound A 21 Amplifier Serial #: ____________________
Parasound Dealer: ____________________________________
Phone Number:_______________________________________
Date of Purchase: _____________________________________
YOU SHOULD KNOW
There is no Parasound warranty for this unit if it was not purchased from an Authorized
Parasound Dealer. Investigate any warranty claims made by unauthorized dealers very
carefully as you will need to depend entirely upon the dealer, and NOT upon Parasound.
Unauthorized dealers may lack the capability to arrange repairs of Parasound equipment.
Authorized Parasound Dealers are listed at www.parasound.com or you can call 415-397-7100
between 8:30 am and 4:30 pm Pacific time.
A missing or tampered serial number could indicate that this unit was stolen or sold by an
unauthorized dealer. If this unit is missing its serial number, you should return it to your
dealer immediately for a full refund.
Page 2
PLACEMENT GUIDELINES FOR YOUR A 21
_________________________________________________________________________________
CONNECTING A STEREO PREAMPLIFIER OR A SURROUND
CONTROLLER TO THE BALANCED INPUTS ON YOUR A 21
_________________________________________________________________________________
CONNECTING A STEREO PREAMPLIFIER OR A SURROUND
CONTROLLER TO THE UNBALANCED INPUTS ON YOUR A 21
_________________________________________________________________________________
CONNECTING THE A 21 LOOP OUT JACKS
TO ANOTHER POWER AMPLIFIERS INPUTS
_________________________________________________________________________________
CONNECTING SPEAKERS TO YOUR A 21
_________________________________________________________________________________
CONFIGURING THE A 21 FOR BRIDGED MONO OPERATION
_________________________________________________________________________________
MANUAL AND AUTOMATIC TURN ON-OFF OPTIONS
_________________________________________________________________________________
CONNECTING AN EXTERNAL DC SOURCE FOR A 21 AUTOMATIC TURN ON-OFF
_________________________________________________________________________________
CONNECTING THE A 21 TO TRIGGER ANOTHER COMPONENT
_________________________________________________________________________________
UNDERSTANDING THE INDICATORS ON THE A 21
_________________________________________________________________________________
CONNECTING THE A 21 AC POWER CORD
_________________________________________________________________________________
MAINTAINING YOUR A 21
_________________________________________________________________________________
TROUBLESHOOTING GUIDE
_________________________________________________________________________________
SERVICING YOUR A 21
_________________________________________________________________________________
TECHNICALLY SPEAKING
_________________________________________________________________________________
PARASOUND A 21 DESIGN OVERVIEW
_________________________________________________________________________________
PARASOUND A 21 SPECIFICATIONS
_________________________________________________________________________________
1 TABLE OF CONTENTS
A 21 Amplifier
19
17
13
12
15
14
11
10
9
8
7
5
4
2
1
3
6
