BOSSCO LMB-3 User manual

1
Owner's Manual
DCAC
AC & BATTERY
POWERED
FET

2
Thank you, and congratulations on your choice of BOSS LMB-3 Bass Limiter Enhancer.
Toensureproperoperation,andyearsoftrouble-freeservice,pleasetakethetimetoread
through this Owner’s Manual before starting out.
FEATURES
• The BOSS LMB-3 is a limiter/enhancer specifically designed for electric bass.
• The LMB-3 allows you to create a well-balanced sound by controlling the volume
difference of the sound or to avoid sound distortion.
• By adjusting the THRESHOLD level and RATIO knobs, the intensity of the limiter can
be spontaneously controlled.
• Using the Enhance effect, you can make the sound clearer and sharper.
© 1995 BOSS Corporation
All right reserved. No part of this publication may be reproduced in any form without the
written permission of BOSS Corporation.

3
IMPORTANT NOTES
When using an AC adaptor, use only the specified device (PSA Series). Use of any other
AC adaptor could result in damage, malfunction or electric shock.
ADDITIONAL PRECAUTIONS
Protect the unit from strong impact.
Should a malfunction occur, or if you sus-
pect there is a problem, discontinue use
immediately. Contact qualified service
personnel as soon as possible.
To avoid the risk of electric shock, do not
open the unit.
CHANGING BATTERY
Removethebatterywhenevertheunitisto
remain unused for an extended period of
time.
POWER SUPPLY
The power requirement for this unit is
indicated on its nameplate (rear panel).
Ensure that the voltage in your installation
meets this requirement.
If the unit is to remain unused for an ex-
tended period of time, unplug the power
cord.
PLACEMENT
Do not subject the unit to temperature
extremes (eg., direct sunlight in an en-
closed vehicle). Avoid using or storing the
unit in dusty or humid areas, or areas that
are subject to high levels of vibration.

4
1
2
3
4
5
6
PANEL DESCRIPTIONS 1. AC Adaptor Jack
Acceptsconnection of anAC Adaptor (op-
tionally available BOSS PSA-Series). By
usinganACAdaptor,youcanplaywithout
being concerned about how much battery
power you have left.
* You may find that it is a good idea to keep a
battery installed in the unit even while using
an adaptor. That way your playing won’t be
disrupted even if the adaptor is accidentally
disconnected.
* If you are going to use an AC adaptor, be sure
to use the specified unit (BOSS PSA-Series).
Use of any other adaptor may result in dam-
age, malfunction or electric shock.
Also, if you are not going to be using it for an
extended period of time, disconnect the AC
adaptor from the AC outlet.

5
2. CHECK Indicator
This indicator shows whether an effect is
ON/OFF, and also doubles as the Battery
Check indicator.
The indicator lights when an effect is ON.
Ifthisindicatorgoesdimornolongerlights
while an effect is ON, the battery is near
exhaustion and should be replaced imme-
diately.
3. OUTPUT Jack
The output jacks are used to connect the
unit to amplifiers or other devices.
4. Pedal Switch
This switch turns the effects ON/OFF.
5. Thumbscrew
This thumbscrew is loosened to open the
pedal, allowing battery replacement. For
instructions on how to replace the battery,
please refer to “CHANGING THE BAT-
TERY”.
6. INPUT Jack
This jack accepts input signals (coming
from a bass guitar, some other musical
instrument, or another effects unit).
* The INPUT Jack also serves as the power
switch.Power isturned onwhenever aplug is
insertedintotheINPUTJack,andisturnedoff
when the plug is disconnected. When not
using the unit, you should disconnect any
cord connected to the INPUT Jack.

6
ENHANCE Knob
This knob adjusts the intensity of the enhance
effectthatmakesthesound clearer and sharper.
Rotating the knob clockwise emphasizes the
effect.
RATIO Knob
This knob controls the compression ratio of the
limiter. That is, it adjusts how much the limiter
shouldcompressthosesignalsabovethethresh-
old level.
*Whenitissetto“1:1”,nolimitereffectwillbe
obtained.
THRESHOLD Knob
This knob controls the threshold level (the level
at which the compression effect will kick in).
Rotating the knob counterclockwise lowers the
threshold level.
For a detailed explanation about the Ratio and
Threshold Level, see “ABOUT THE LIMITER'S
ACTION”.
LEVEL Knob
This knob adjusts the level of the effect sounds.
Set the knob so there is no volume difference
between the effect and straight guitar sounds.
* If this knob is rotated completely counter-
clockwise, no sound will be heard.
CHECK
ENHANCE LEVEL
MIN MAX 1:1 ∞
:1
RATIO THSHD
MIN MAXMIN MAX
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
LEVEL Knob
ENHANCE Knob
THRESHOLD Knob
RATIO Knob

7
AC Adaptor (PSA-Series ; Optional)
Electric Bass
Amplifier
OUT 9V DC / 200mA
MAKING THE CONNECTIONS
* Inserting a plug into the Input Jack will automatically switch the unit on.
*Beforeconnectingordisconnectinganypatchcords,besureallthevolumecontrolsinyoursystem
are set to minimum. This will help prevent any damage to system components.

8
CHECK
ENHANCE LEVEL
MIN MAX 1:1∞:1
RATIO THSHD
MIN MAXMIN MAX
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
OPERATING THE UNIT
1.Whenyouhavemadethenecessaryconnections,setthe
knobs as shown in the illustration.
2.Depressthepedalswitchtoturntheeffecton.(Makesure
that the CHECK Indicator lights.)
3. Adjust the Threshold Level (the level at which compres-
sion starts) using the THRESHOLD Knob.
4. Adjust the compression ratio using the RATIO Knob.
5. Adjust the intensity of the enhance effect using the
ENHANCE Knob.
6. Adjust the LEVEL Knob so there will be no volume
difference between the effect and straight bass sounds.
CHECK
ENHANCE LEVEL
MIN MAX 1:1∞:1
RATIO THSHD
MIN MAXMIN MAX
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
6543

9
ABOUT THE LIMITER'S ACTION
The LMB-3’s limiter will function differently depending upon how you set the Ratio and
Threshold Levels. The RATIO and THRESHOLD knobs work as described below.
RATIO : The compression ratio for the input signal is called Ratio. For instance,
when the Ratio is set to “2:1”, an input signal that is 6 dB louder than the
Threshold Level will be compressed to one half, or 3 dB When it is set to
“∞:1”, any input signal above the Threshold Level will be compressed to
the Threshold Level, then output.
THRESHOLD : The Threshold Level is the level at which compression starts to work.
Whenthe input signalhas reached theThreshold Level, thesignal will be
compressed at the compression ratio set with “RATIO”, then output.
When the input signal is lower than the Threshold Level, it will be output
without compression.

10
The following figure shows how the output signal is affected by the settings of the RATIO
and THRESHOLD knobs.
a
b
Threshold Level
Ratio = a : b
Input Level (dBm)
Output Level (dBm)
1:1
2:1
∞ :1
Threshold Level
Input Level (dBm)
Output Level (dBm)

11
Thumbscrew
Pedal
Spring Base
Coil Spring
Guide
Bush
Hole
Battery
Housing
Battery Snap Cord
Battery Snap
9V Battery
CHANGING THE BATTERY
Whentheindicatorgoesdim or no longerlights
while an effect is on, it means that the battery is
nearly dead and must be replaced.
Replace the battery following the steps below.
1. Loosen the thumbscrew at the front of the
pedal,thenliftthepedalupwardstoopenthe
unit.
* The thumbscrew can be left in the pedal
while changing the battery.
2. Remove the old battery from the battery
housing, and remove the snap cord con-
nected to it.
3.Connectthesnapcordtothenewbattery,and
place the battery inside the battery housing.
* Be sure to carefully observe the battery+s
polarity (+ versus -).
4.Slipthecoilspringontothespringbaseonthe
back of the pedal, then close the pedal.
*Carefullyavoidgettingthesnapcordcaught
in the coil spring.
5.Finally, insert the thumbscrew into the guide
bush hole and fasten it securely.

12
SAMPLE SETTING
Limiter Enhancer
Finger Picking Slapping Play
CHECK
ENHANCE LEVEL
MIN MAX 1:1∞:1
RATIO THSHD
MIN MAXMIN MAX
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
CHECK
ENHANCE LEVEL
MIN MAX 1:1∞:1
RATIO THSHD
MIN MAXMIN MAX
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
CHECK
ENHANCE LEVEL
MIN MAX 1:1∞:1
RATIO THSHD
MIN MAXMIN MAX
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
CHECK
ENHANCE LEVEL
MIN MAX 1:1∞:1
RATIO THSHD
MIN MAXMIN MAX
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3

13
SETTING MEMO
CHECK
ENHANCE LEVEL
MIN MAX 1:1 ∞
:1
RATIO THSHD
MIN MAXMIN MAX
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
CHECK
ENHANCE LEVEL
MIN MAX 1:1∞:1
RATIO THSHD
MIN MAXMIN MAX
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
CHECK
ENHANCE LEVEL
MIN MAX 1:1 ∞
:1
RATIO THSHD
MIN MAXMIN MAX
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
CHECK
ENHANCE LEVEL
MIN MAX 1:1∞:1
RATIO THSHD
MIN MAXMIN MAX
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3
L
M
B
-
3

14
SPECIFICATIONS
LMB-3 : Bass Limiter Enhancer
Nominal Input Level ................. -20 dBm
Input Impedance ...................... 1 MΩ
Nominal Output Level .............. -20 dBm
Output Impedance ................... 1 kΩ
Recommended Load Impedance 10 kΩor greater
Residual Noise Level................. -86 dBm (IHF-A, Typ.)
Controls.................................... Pedal Switch, LEVEL Knob, ENHANCE Knob,
RATIO Knob, THRESHOLD Knob
Indicator................................... CHECKIndicator(servesalsoasbatterycheckindicator)
Connectors ............................... INPUT Jack, OUTPUT Jack, AC Adaptor Jack (9 V DC)
Power Supply ........................... 9 V DC : Dry Battery 9 V type (6F22/9 V), AC Adaptor
Current Draw ........................... 17 mA (9 V DC)
* Expected battery life under continuous use :
Carbon : 12 hours
These figures will vary depending on the actual condi-
tions of use.

15
Dimensions............................... 70 (W) x 125 (D) x 55 (H) mm
2-3/4 (W) x 4-15/16 (D) x 2-3/16 (H) inches
Weight...................................... 430 g / 15 oz (including battery)
Accessories ............................... Owner’s Manual, Dry Battery 9 V type (6F22/9 V),
Roland Service
Options .................................... AC Adaptor PSA-Series
* 0 dBm = 0.775 V rms
* In the interest of product development, the specifications and/or appearance of this unit are
subject to change without prior notice.
This product complies with the requirements of
European Directive 89/336/EEC.
For EU Countries

16 00678767