JBL PowerBass PB12 Service Manual - page 4
JBL PB 12
250W Powered Sub Amp
LINE VOLTAGE
Yes/No
Hi/Lo Line
Nom.
Unit
Notes
US 120vac/60Hz
Yes
108-132
120
Vrms
Normal Operation
EU 230vac/50-60Hz
Yes
207-264
230
Vrms
Normal operation, MOMS required
Parameter
Specification
Unit
QA Test
Limits
Conditions
Notes
Amp Section
Type (Class AB, D, other)
D
n/a
n/a
Load Impedance (speaker)
5.6
Ohms
n/a
Nominal
Rated Output Power
250
Watts
145
1 input driven
Peak
THD @ Rated Power
0.3
%
1
22k filter
145 Watts
THD @ 1 Watt
0.1
%
0.5
22k filter
DC Offset
10
mV-DC
20
@ Speaker Outputs
Damping factor
>50
DF
35
Measured at amplifier board
Measured at the speaker cable. 150 Watts @
THD < 0.1 % @ 50 Hz
Input Sensitivity
Input Frequency
50
Hz
50
Nominal Freq.
L&R
240
mVrms
±2dB
To 150 Watts
Single input driven
LFE input
240
mVrms
±2dB
To 150 Watts
Single input driven, LFE switch ON
Speaker/Hi Level Input
2.4
Vrms
±2dB
To 150 Watts
Single input driven
Signal to Noise
SNR-A-Weighted
90
dBA
80
relative to rated power
A-Weighting filter
SNR-unweighted
85
dBr
80
relative to rated power
22k filter
SNR rel. 1W-unweighted
65
dBr
60
relative to 1W Output
22k filter
Residual Noise Floor
1
mVrms
2
Volume @max, using RMS reading
DMM/VOM (or A/P) BW=20 Khz.
Residual Noise Floor
1.5 mVrms(max)
2
Volume @max, w/ A/P Swept
Bandpass Measurement (Line
freq.+ harmonics) (BW=20 Khz)
Input Impedance
Line Input (L, R,LFE)
20K
ohms
n/a
Nominal
Speaker/Hi Level Input
4.7K
ohms
n/a
Nominal
Filters
LP filter 4th order fixed
60-180 Hz
± 10
2nd order variable + 2nd order fix-24 db/Octave
Subsonic filter (HPF) 2nd Order
Fixed
LFE Low pass 2nd order
200>LP<1K Hz
LFE input driven only
HP speaker out connector
200 Hz
± 10
Speaker input driven - 4 Ohms
100 Hz
± 10
Speaker input driven - 8 Ohms
Limiter
THD at Max. Output Power
n/a
n/a
functional Maximum Output Power
Maximum THD as a result of limiting.
Features
--
Volume pot Taper (lin/log)
LOG
--
functional
A Taper
HP Speaker out
YES
functional
Refer to Filter section
Phase switch
0-180
deg
functional
LP Filter defeat switch
YES
functional
Disables LP filter, intended for LFE
Input Configuration
Line In (L,R) & LFE
YES
--
functional
Dual RCA jack
Spkr/Hi Level In
YES
--
functional
Binding post connector L&R
Signal Sensing (ATO)
Auto-Turn-On (yes/no)
YES
functional
ATO Input test frequency
50
Hz
functional
"
ATO Level LFE Input
4
mV
functional
"
Maximum acceptable level.
ATO Level Speaker in
50
mV
functional
"
Maximum acceptable level.
ATO Turn-on time
5
ms
functional
Amp connected and AC on, then
input signal applied
Auto Mute/ Turn-OFF Time
15
minutes
15
T before muting, after signal
removed
Auto turn of time (T) must be 5 > T < 15
Minutes
Power on Delay time
3
sec.
4
AC Power Applied
Transients/Pops
ATO Transient
5
mV-peak
n/a
@ Speaker Outputs
Turn-on Transient
50
mV-peak
2v-pp
@ Speaker Outputs
AC Line cycled from OFF to ON
Turn-off Transient
50
mV-peak
2v-pp
@ Speaker Outputs
AC Line cycled from ON to OFF
Efficiency
Efficiency
65
%
64
Nominal Line voltage 120 VAC
Stand-by Input Power
24
Watts
26
@ nom. line voltage
Power Cons. @ rated power
234
Watts
240
@ nom. line voltage
150 Watts @ 5.6 Ohms nominal line voltage
Short Circuit Protection
YES
functional Direct short at output
Amplifier should resume operation after short
Thermal Protection
YES
functional
DC Offset Protection
YES
-
DC present at Speaker Out leads
Line Fuse Rating
USA-Domestic (120v)
2
Amps
Type-T or Slo Blo-250 V
EU (230v)
1
Amps
Type-T or Slo Blo-250 V
External fuse with UL/SEMKO rated holder