![](http://pdfasset.owneriq.net/6/e3/6e395695-2ee4-4998-a86f-c8e742c297ae/6e395695-2ee4-4998-a86f-c8e742c297ae-bgc.png)
PB
681X
frequency response
power supply voltage
output power @ 14.4v DC, 1KHz
RMS Power @ 4 Ohms
RMS Power @ 2 Ohms
Maximum Power Output
input sensitivity
low level inputs
high level inputs
35 Watts x 4
55 Watts x 4
250 Watts x 4
15 Hz-30 KHz
250mV
2.5V
14.4V DC Neg. Ground (10.5-16V)
PB
881X
50 Watts x 4
60 Watts x 4
300 Watts x 4
maximum current draw
dimensions (W x H x L)
mm
inches
2-4 Ohms
4-8 Ohms
matching speaker impedance
stereo mode
bridged mode
input impedance
low level inputs
high level inputs
10K Ohms
100 Ohms
20 A 30 A
276 x 60 x 305
10.9 x 2.4 x 12
276 x 60 x 394
10.9 x 2.4 x 15.5
dual crossover mode selectors
dual input level controls
dual low pass frequency controls
dual high pass frequency controls
dual bass boost level controls
low level inputs
high level inputs
power LED
protection LED
power fuse
power terminals
speaker connections
when used with normal, full range systems, set these switches to “FULL.”
If you wish to use the internal crossovers to power a driver of specific
frequency range, use the “LOWPASS” or “HIGHPASS” settings.
use these controls to match the outputs of your head unit to the amplifier.
Starting with your head unit set at about the 2 o’clock position, increase
the amp level controls until distortion begins to occur, and reduce slightly
from this point.
when one or both of the crossover selector switches is in “low pass”
mode, one can set the upper frequency limit for audio program sent to
the speakers.
when the one or both of crossover selector switch is in “high pass” mode,
one can set the lower frequency limit for audio program sent to the
speakers.
this control permits adjustment of the bass level up to an increase of
approximately 18 dB in either or both pairs of channels.
this amp features gold-plated RCA input jacks for high impedance input.
Use these with car stereo output which uses RCA-type connector cables.
if your car stereo lacks RCA-type output jacks, you may connect speaker
output leads to these input connectors.
this indicator is illuminated when power is applied.
this indicator is illuminated when built-in protection circuitry is activated.
the fuse protects the amplifier and your car’s electrical system from short
circuit conditions.
use these connectors to deliver power, ground and remote turn-on control
to the amplifier.
these terminals are 14K gold plated to guarantee high conductivity and
minimum signal loss.
11
features and specifications
4 ch amp PB681X • PB881X