JBL GTS300 Home Theater System User Manual


 
3. System Design Using the
GTS300 or GTS600:
3.1 Speaker Requirements
When used in the non-bridged
mode the GTS300 or GTS600 can
easily drive 2 ohm speaker loads.
When only one speaker is
connected to each channel,
virtually any conventional speaker
may be used.
When the GTS300 or GTS600 is in
bridged mode, the combined
impedance of the speaker (or
speakers) connected to the bridged
channel should be at least 4 ohms.
Sustained operation of the GTS300
or GTS600 in bridged mode with
less than 4 ohms will likely cause
overheating.
The GTS300 or GTS600 must not
be used with speakers that have
either one of their input terminals
wired to the frame of the speaker
or to the chassis of the vehicle.
3.2 Signal Sources
The low level preamp outputs of
any radio/tape deck, CD player or
preamp/equalizer so equipped can
drive the GTS300 or GTS600. The
gain controls of the GTS300 or
GTS600 are used to match the
amplifier’s input sensitivity to the
output voltage of the source. This
matching is important to keep
noise low and is explained in the
“Adjusting the Gain” section of
this manual.
Thanks to Universal Interface
Circuitry, the GTS300 or GTS600
can also be connected to power
amplifiers, radios or equalizers
that are equipped with only
speaker outputs by connecting
them through the speaker level
input connector. Inside the GTS300
or GTS600, the speaker-level and
preamp-level inputs are connected
through a mixing circuit, which
allows them to be used
simultaneously. Therefore a low
level source, such as a CD player
equippe with a volume control
may be connected to the preamp-
level inputs at the same time as a
powered radio/tape unit is
connected to the speaker-level
inputs. This provides a higher
performance alternative to an FM
Modulator connection when you
wish to add CD capability to a
factory casette stereo. Switching
from one source to the other is as
simple as turning the desired
source on and turning the
undesired one off – no additional
switches or relay connections are
needed.
4. Wiring
Proper wiring of the GTS300 or
GTS600 and the associated
4
(+)
(–)
(+)
(–)
Parallel Wiring
Series Wiring
2 Ohms
Nominal
Impedance
8 Ohms
Nominal
Impedance
4 Ohms
4 Ohms
4 Ohms 4 Ohms