SUB 150P - JBL Audio Service Manual (repair manual). Page 5

tuRning the subwoofeR on and off
Set the subwoofer’s Power Switch to the “On” position. The subwoofer will 

automatically turn itself on when it receives an audio signal, and it will go 

into Standby mode after it has received no audio signal for approximately 

10 minutes. The subwoofer’s LED will glow green when the subwoofer is 

on and will glow red when the subwoofer is in Standby.

If you will not be using the subwoofer for an extended period – for 

instance, if you’re going on vacation – set the Power Switch to the “Off” 

position.

subwoofeR adJustments: cRossoveR contRol
NOTE: The Crossover control functions only 

when the Input Mode switch is in the “Normal” 

position. 

The Crossover control adjusts the subwoofer’s 

built-in low-pass filter crossover between 

50Hz and 200Hz. The higher you set the 

Crossover control, the higher in frequency the 

subwoofer will operate and the more its bass will “overlap” that of the 

satellite speakers. This adjustment helps achieve a smooth transition of 

bass frequencies between the subwoofer and the satellites for a variety of 

different rooms and subwoofer locations.

To set the Crossover control, listen for the smoothness of the bass. If 

the bass seems too strong at certain frequencies, try a lower Crossover 

control setting. If the bass seems too weak at certain frequencies, try a 

higher Crossover control setting.

subwoofeR adJustments: volume
Use the Level control to set the subwoofer’s 

volume. Turn the knob clockwise to increase 

the subwoofer’s volume; turn the knob 

counterclockwise to decrease the volume. Once 

you have balanced the subwoofer’s volume 

with that of the other speakers in your system, 

you shouldn’t have to change the Level control 

setting.

Notes on Setting Subwoofer Volume:

•  Sometimes the ideal subwoofer volume setting for music is too loud 

for films, while the ideal setting for films is too quiet for music. When 

setting the subwoofer volume, listen to both music and films with 

strong bass content and find a “middle ground” volume level that 

works for both. 

•   If your subwoofer always seems too loud or too quiet, you may want 

to place it in a different location. Placing the subwoofer in a corner will 

tend to increase its bass output, while placing it away from any walls 

or corners will tend to lessen its bass output.

subwoofeR adJustments: Phase
The Phase switch determines whether the subwoofer 

driver’s piston-like action moves in and out in phase 

with the satellite speakers. If the subwoofer were to 

play out of phase with the satellite speakers, the sound 

waves from the satellites could partially cancel out the 

waves from the subwoofer, reducing bass performance 

and sonic impact. This phenomenon depends in part on the placement of 

all the speakers relative to each other in the room. 

Although in most cases you should leave the Phase switch in the “Normal” 

position, there is no absolutely correct setting for the Phase switch. When 

the subwoofer is properly in phase with the satellite speakers, the sound 

will be clearer and have maximum impact, and percussive sounds like 

drums, piano and plucked strings will sound more lifelike. The best way 

to set the Phase switch is to listen to music that you know well and to set 

the switch in the position that gives drums and other percussive sounds 

maximum impact.

is a trademark of HARMAN International Industries, Incorporated.
Features, specifications and appearance are subject to change without notice.
Part No. 950-0328-001

HARMAN Consumer, Inc. 

www.jbl.com

Low-frequency 

transducer:

10" (250mm) PolyPlas cone (down-firing)

Enclosure type:

Ported (down-firing)

Amplifier power:

300 watts (RMS); 500 watts (peak)

Frequency response:

27Hz – 150Hz (–3dB)

Audio controls:

Volume level, crossover frequency, phase

Connections:

RCA line-level and LFE inputs

Power requirement:

120V, 60Hz (US); 220V – 230V, 50Hz/60Hz 

(EU)

Power consumption:

<1W (0.040A @ 230V) standby; 

320W (1.8A @ 230V) peak 

<6W (0.06A @ 120V) standby; 

320W (3.2A @ 120V) peak

Dimensions (W x H x D):

17-3/8" x 18-1/2" x 17-3/8"  

(441mm x 470mm x 441mm)

Weight:

39.7 lb (18.0kg)

0242CSK - JBL SUB150P OM_v3.indd   4

29/09/10   9:57:52

JBL

SUB 150P/230 Service Manual

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