dbx Pro 260 - Manual (Page 81)

®
The 260 DriveRack gives you the option of changing the input gain level settings. There are 3 hardware configurable
gain settings. They are: +14 dBu, +22 dBu and +30 dBu. For these cases, use the following procedure to change the
gain level settings. Please be advised however, that once the gain level has been changed from the factory settings, the
output meters will no longer be calibrated correctly.
To change the gain level, move the jumpers to the pins that are marked with the desired gain setting
1) First, make sure that the unit has been shut off and unplugged prior to opening the unit.
2) Ground yourself prior to opening the DriveRack™ chassis to prevent ESD damage.
3) Open the chassis by removing five screws on each side of the chassis and the top two center screws on the rear panel,
as well as the top center allen screw located on the front panel
4) Locate the jumper block shown in the illustration below:
The DriveRack 260 offers a wide range of tools for sound system design and setup. These tools
can make your system more efficient and better sounding, but to get the best possible sound it
is important to use these tools properly. In the DriveRack 260 we have included a Wizard setup
tool to help in system setup. If you use the Wizard to set up your DriveRack 260 it will auto-
matically set the limiters for some amplifier selections. If your amplifiers are not available in
the Wizard, you should choose the Custom setting. The following section explains how to max-
imize system gain and how to use the limiters to protect your amplifiers from clipping.
In traditional system design, the output of your console would be routed to a system EQ, a com-
pressor, and a crossover with output level control. From the crossover, there may be addition-
al filters that are employed to improve the response of your speakers. There may also be lim
iters set up to keep your amplifiers from going into clipping and protect your speakers from
the hazards of a clipped signal. Your amplifiers play a vital role in system setup, because they
are last item in the chain before your speakers and offer the greatest amount of gain (that is
their job after all). If your amplifiers are incorrectly setup you will not be using your system to
its fullest potential and could be harming your speakers.
A.10 System Setup and Gain Structure
Output Jumpers
Input Jumpers
+22dBu
Ch1
+30dBu
+14dBu
+22dBu
Ch2
+30dBu
+14dBu +22dBu
Ch1
+30dBu
+14dBu
+22dBu
Ch2
+30dBu
+14dBu
+22dBu
Ch3
+30dBu
+14dBu
+22dBu
Ch4
+30dBu
+14dBu
+22dBu
Ch5
+30dBu
+14dBu
+22dBu
Ch6
+30dBu
+14dBu
CAUTION: These servicing instructions are for use by qualified service
personnel only. To reduce the risk of electric shock, do not perform any
servicing other than that contained in the operating instructions unless you
are qualified to do so. Refer all servicing to qualified service personnel.
Disconnect mains power before servicing.
A.9 Gain Level Jumpers
Appendix A
DriveRack ™
DriveRack™ User Manual 73