GTH 400 (serv.man2) - JBL Car Audio User Guide / Operation Manual. Page 14

13

Regardless of whether you build or buy
it, the necessary resistor network has
the following configuration:

•Each resistor in the package has the

same value.

•If you know the crossover frequency

you want, you can calculate the
resistor value necessary by solving the
following equation:

2,500,000

Frequency in Hz 

•Use the following equation if you have

a resistor pack of a known value, and
want to find its crossover frequency:

2,500,000

Resistor Value

in ohms

•To build chips from discrete resistors,

solder the resistors to a standard 14-
pin “DIP Header” according to the
diagram. If a DIP Header is not
available, you may bend the leads of

1

⁄

4

-watt resistors 90 degrees, trim them

to 

1

⁄

8

"-length, and insert them directly

into the chip sockets.

To change the crossover frequency
change the resistor network as follows:

1. Remove the screws from the

bottom panel as shown below.

2. Select which resistor module, high

pass or low pass, that you wish to
change.

3. A chip puller, which can be

obtained from any electronics store,
is recommended to remove the
resistor chip. Pull the resistor chip
from the socket as shown in the
figure below.

4. Place the new module in the socket

making sure all pins are lined up
with the socket holes. Press the
module firmly into the socket.

5. Replace the bottom lid.

For further information on how to use
the speaker output and preamp output
crossovers for system building see the
“Typical Applications” and “Add-On
and Upgrade Steps” sections.

The wired remote of the GTH400 can be
installed either in dash or under dash.

HIGH PASS

FILTER

FREQUENCY

SELECTION

MODULE

LOW PASS

FILTER

FREQUENCY

SELECTION

MODULE

C10

C13

JBL INC.

NORTHRIDGE, CA

JBL GTS600

PC00108800

REV A

CROSSOVER

GTH400-20107  06/03/98 15:49  Side 13