JBL GT1200 Instruction manual

SPECIFICATIONS
DIAMETER: 12" (304.8 MM)
SENSITIVITY (2.83 V @ 1 M): 95 dB
POWER HANDLING: 280 WRMS
FREQUENCY RESPONSE: 25 ~ 3,000 HZ
NOMINAL IMPEDANCE:4OHMS
VOICE-COIL DIAMETER: 2.0" (50.7 MM)
DIMENSIONS:
THIELE-SMALL PARAMETERS
VOICE COIL DCRESISTANCE:R
EVC (OHMS) . . . . . . 3.17
VOICE COIL INDUCTANCE @ 1 KHZ:L
EVC (MH). . . . . . . . 2.16
DRIVER RADIATING AREA:S
D(IN2) . . . . . . . . 82.10
SD(CM2). . . . . . . 532.00
MOTOR FORCE FACTOR:BL(TM) . . . . . . . . 12.82
COMPLIANCE VOLUME:V
AS (FT3). . . . . . . . . 6.60
VAS (LITERS). . . . . 155.73
SUSPENSION COMPLIANCE:C
MS (µM/N) . . . . 387.48
MOVING MASS, AIR LOAD:M
MS (GRAMS) . . . . 105.69
MOVING MASS, DIAPHRAGM:M
MD (GRAMS). . . . . 98.64
FREE-AIR RESONANCE:F
S(HZ) . . . . . . . . 24.80
MECHANICAL Q: QMS . . . . . . . . . . . 11.76
ELECTRICAL Q: QES . . . . . . . . . . . . 0.32
TOTAL Q: QTS . . . . . . . . . . . . 0.31
MAGNETIC-GAP HEIGHT:H
AG (IN) . . . . . . . . . 0.31
HAG (MM) . . . . . . . . 7.92
VOICE-COIL HEIGHT:H
VC (IN) . . . . . . . . . 0.88
HVC (MM) . . . . . . . 22.23
MAXIMUM EXCURSION:X
MAX (IN) . . . . . . . . .0.28
XMAX (MM). . . . . . . . 7.15
IMPEDANCE CURVE
INFINITE BAFFLE
FREQUENCY RESPONSE @ 2.83 V
INFINITE BAFFLE
EXCURSION/GROUP DELAY @ 75 W
GT1200 12" Woofer – Technical Data
7•20 . . . . . JBL Technical Data
Ohms
100.0
1.0
3.0
10.0
30.0
20 Frequency 50 100 Hz 200 500 1k 2k
C
dB
105
100
95
90
85
80
75
70
65
20 Frequency 50 100 Hz 200 500 1k 2k
Out-Of-Car
In-Car
12 dB LP @ 80 Hz
C
Xd mM
20.0
17.5
15.0
12.5
10.0
7.5
5.0
2.5
0.0
T mSec 10.0
7.5
5.0
2.5
0.0
-2.5
-5.0
-7.5
-10.0
20 Frequency 50 100 Hz 200 500 1k 2k
Transducer Excursion
Group Delay
mounting depth
5.75" (146.05 mm)
cutout diameter
11.13" (283.00 mm)
outer diameter
12.18" (309.44 mm)

VBOX = 1.20 ft3 (33.98 liters)
(all sides lined with 1-inch fiberglass or fiberfill)
GT1200
(side view)
C
dB
100
95
90
85
80
75
70
65
60
20 Frequency 50 100 Hz 200 500 1k 2k
Out-Of-Car
In-Car
12 dB LP @ 90 Hz
C
Xd mM
20.0
17.5
15.0
12.5
10.0
7.5
5.0
2.5
0.0
T mSec 10.0
7.5
5.0
2.5
0.0
-2.5
-5.0
-7.5
-10.0
20 Frequency 50 100 Hz 200 500 1k 2k
Transducer Excursion
Group Delay
GT1200
(side view)
Port
fo= 30 Hz
diameter = 4.0"
length = 14.00"
VBOX = 1.80 ft3 (50.98 liters)
(all sides lined with 1-inch fiberglass or fiberfill)
C
dB
105
100
95
90
85
80
75
70
65
20 Frequency 50 100 Hz 200 500 1k 2k
Out-Of-Car
In-Car
12 dB LP @ 90 Hz
C
Xd mM
20.0
17.5
15.0
12.5
10.0
7.5
5.0
2.5
0
T mSec 20
15
10
5
0
-5
-10
-15
-20
20 Frequency 50 100 Hz 200 500 1k 2k
Transducer Excursion
Group Delay
SEALED
BOX VOLUME
SEALED
FREQUENCY RESPONSE @ 2.83 V
SEALED
EXCURSION/GROUP DELAY @ 250 W
VENTED
BOX VOLUME
VENTED
FREQUENCY RESPONSE @ 2.83 V
VENTED
EXCURSION/GROUP DELAY @ 275 W
GT1200 12" Woofer – Technical Data
JBL Technical Data . . . . . 7•21

SEALED BANDPASS
BOX VOLUME
SEALED BANDPASS
FREQUENCY RESPONSE @ 2.83 V
SEALED BANDPASS
EXCURSION/GROUP DELAY @ 200 W
NOTES
GT1200 12" Woofer – Technical Data
7•22 . . . . . JBL Technical Data
VREAR = 1.20 ft3 (33.98 liters)
(all sides lined with 1-inch fiberglass or fiberfill)
VFRONT = 0.50 ft3
(14.16 liters)
GT1200
(side view)
diam. = 4"
Port
fo= 70 Hz
length =
8.11"
C
dB
100
95
90
85
80
75
70
65
60
20 Frequency 50 100 Hz 200 500 1k 2k
Out-Of-Car
In-Car
12 dB LP @ 95 Hz
C
Xd mM
20.0
17.5
15.0
12.5
10.0
7.5
5.0
2.5
0.0
T mSec 40
30
20
10
0
-10
-20
-30
-40
20 Frequency 50 100 Hz 200 500 1k 2k
Transducer Excursion
Group Delay