JBL PB12 Service Manual

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

JBL PB12 Specifications

General

Type	Powered
Woofer Size	12 inches
Frequency Response	150 Hz
Enclosure Type	Bass Reflex
Low Pass Crossover	50Hz - 150Hz