Operation Manual, RA2400 & RA7300 Power Amplifiers
Page 19
Document # 9301H62800 Ver. 1.00
DATASAT SERVICE INFORMATION
The RA2400/RA7300 do not contain any internal user serviceable parts. If you suspect a problem
that may require service assistance, contact Datasat Technical Support.
It is important that only an authorized service agent carry out any/all repairs. This will ensure
proper service and preserve the protection of your Limited Warranty. Keep the sales slip or receipt
in a safe place with this manual so that it will be available to verify the purchase date. It will also
be needed should you experience a problem covered by warranty. If you need to contact Datasat
Technical Support or Customer Service, be ready to provide your amplifier’s serial number, a
description of the problem and your contact information. Before returning the amplifier, be sure to
obtain a return authorization (RA) prior to shipping the unit.
USA
Technical Support Email:
Tel: 1(888)428-2268
Customer Service Email:
Tel: 1(818) 531-0003
Europe
Email:
Tel: +44 (0)118 934 9199
RA2400/RA7300 updates and technical information is available at
www.datasatdigital.com/docs/consumer/
A FEW WORDS ABOUT HUM AND NOISE
One of the main benefits of the Pure Balance
®
design is its ability to reject hum often referred to as
CMR or Common Mode Rejection. The Pure Balance circuitry is engaged when using the XLR and
DB25 connectors on the RA2400/RA7300,
and
on the preamp or other source device being used.
Audible hum or a discernable low frequency noise is one of the most common problems in
audio/video systems. This hum is usually caused by a problem known as “ground loops” and may
be present even when the volume is at a low level. A ground loop occurs when there is a difference
in ground voltages between two or more components that are electrically connected. This, in turn,
creates multiple current paths which cause low-level noise or hum.
The potential for ground loops increases with the growing sophistication and complexity of home
audio/video systems and the increased number of components used to create these systems.
Although it is natural to suspect that the components in your sound system are the cause of the
hum, it’s also possible that it may be caused by other conditions. In particular, cable TV
connections from outside the home have been found to be a major source of hum.
If you encounter a hum problem in your sound system, please try the suggestions below, in the
