Parasound A 52 manual Technically Speaking

Page 17

TECHNICALLY SPEAKING continued

15

 

 

The ideal of zero voltage ground for all the compo- nents in a system is practically impossible, because some resistance between the ground points of differ- ent components is inevitable. By keeping components close together with their power cords plugged into a common AC outlet or power strip, you’ll avoid the problems created by resistance in the house’s wiring.

Hum and buzz is also caused when unwanted voltage flows through multiple component ground points called ground loops. Here are three tips to avoid ground loops:

1.Use balanced input lines with your Parasound A 52. (See Balanced and Unbalanced Lines in this section)

2.When rack mounting, always use insulated “shoul- der” washers. These break the ground loops caused by metal-to-metal contact between the rack, the components, and their rack-mount bolts. Extra wash- ers are available from rack manufacturer Middle Atlantic Products, www.middleatlantic.com.

3.Use the Ground switch on the A 52 to eliminate most ground loops. This separates the A 52s sig- nal input ground from its chassis ground to isolate unwanted voltage in the ground shield of the unbalanced (RCA) input cable. Be sure your system installation is finished before you try moving the Ground switch from its Normal to its Lift position.

Ground Switch, set to up position

Parasound Products, Inc.

San Francisco, CA USA

L U C A S F I L M

Manufactured under license from Lucasfilm Ltd. Lucasfilm and THX are registered Trademarks of Lucasfilm Ltd.

CAUTION

To Prevent Electric Shock, Do Not

Remove Cover. No User-Serviceable

Parts Inside, Refer Servicing To

Qualified Service Personnel.

Ch 1

Ch 2

Ch 3

Ch 4

Ch 5

Balanced

Balanced

Balanced

Balanced

Balanced

Input

Input

Input

Input

Input

Unbalanced

Unbalanced

Unbalanced

Unbalanced

Unbalanced

Balanced

 

Audio

Sensitivity

Lift

 

 

 

50 mV 250

 

 

 

Man

 

 

Unbalanced Output

Input

12 V

 

Normal

Inputs

 

 

 

Ground

Auto Turn On

WARNING

To Prevent Fire Or Shock Hazard,

Do Not Expose This Unit To Rain

Or Moisture.

Fuse

T15A/250V1-115V Area

T8A/250V-230V Area

AC 115V

60Hz

AC 230V

50Hz

Power Consumption: 1350W

Image 17
Contents Amplifier Congratulations and Thank You for Choosing Parasound Thank YOUParasound Staff Unpacking Your a Keeping Records for Future ReferenceTable of Contents To attach the rack mount brackets Placement Guidelines for Your aRack Mounting Your Parasound a Balanced XLR Jacks and Their Pin Configuration Before ConnectingLeft and Right Balanced Input Jacks What You’ll NeedWrite Down Your Connections Ch 1-5 Unbalanced InputsSpeaker Wire Length and Gauge thickness Connecting Your Speakers to the aSpeaker Terminals Correct Speaker Polarity is ImportantManual and Automatic Turn ON-OFF Options Connecting an Active Audio Source for Automatic On-OffTurn Off Delay in the Audio Mode Audio Turn On Switch Set to down position Connecting AN External DC Source for Automatic Turn ON-OFFConnecting the a 52 to Trigger Another Component Channel Status Indicators On, Off and Fault/Protection Status IndicatorsAll Indicators Illuminated High-Temp Indicator120 V or 220 V 240 V Operation Connecting the a 52 AC Power CordAC Power Connections Maintaining Your a Trouble Probable Cause Remedy Troubleshooting GuideServicing Your a Procedure for Returning Your a 52 to Parasound for ServiceIf All Else Fails -Call Us for Help Important Notice Shipping the aTechnically Speaking Audio Trigger Sensitivity AdjustmentTechnically Speaking Circuit Designed by John Curl Parasound a 52 Design OverviewParasound a 52 Design Overview Parasound a 52 Specifications Parasound Products, Inc Battery Street, San Francisco, CA