User's Manual
DJM-4
3-CHANNEL VCA -CONTROLLED
DJ MIXER WITH BEAT COUNTER
R
LTO
www.altoproaudio.com
Version 2.0 August 2003
English
the recommended fuse type as indicated in this manual.
Do not short-circuit the fuse holder. Before replacing the
fuse, make sure that the product is OFF and disconnected
from the AC outlet.
SAFETY RELATED SYMBOLS
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
Protective Ground
This symbol, wherever used, alerts you to the presence of un-insulated and dangerous voltages within the product enclosure. These are voltages that
may be sufficient to constitute the risk of electric
shock or death.
Before turning the product ON, make sure that it is
connected to Ground. This is to prevent the risk of
electric shock.
Never cut internal or external Ground wires. Likewise,
never remove Ground wiring from the Protective Ground
Terminal.
This symbol, wherever used, alerts you to important operating and maintenance instructions.
Please read.
Operating Conditions
Always install in accordance with the manufacturer's
instructions.
Protective Ground Terminal
To avoid the risk of electric shock and damage, do not
subject this product to any liquid/rain or moisture. Do
not use this product when in close proximity to water.
AC mains (Alternating Current)
Hazardous Live Terminal
ON:
Denotes the product is turned on.
Do not install this product near any direct heat source.
OFF: Denotes the product is turned off.
Do not block areas of ventilation. Failure to do so could
result in fire.
Keep product away from naked flames.
WARNING
Describes precautions that should be observed to
prevent the possibility of death or injury to the user.
IMPORTANT SAFETY INSTRUCTIONS
CAUTION
Read these instructions
Describes precautions that should be observed to
prevent damage to the product.
Follow all instructions
Keep these instructions. Do not discard.
Heed all warnings.
WARNING
Only use attachments/accessories specified by the
manufacturer.
Power Supply
Ensure that the mains source voltage (AC outlet) matches
the voltage rating of the product. Failure to do so could
Power Cord and Plug
result in damage to the product and possibly the user.
Unplug the product before electrical storms occur and
when unused for long periods of time to reduce the risk of
Do not tamper with the power cord or plug. These are
designed for your safety.
electric shock or fire.
If the plug does not fit your AC outlet seek advice from a
qualified electrician.
Do not remove Ground connections!
External Connection
Always use proper ready-made insulated mains
cabling (power cord). Failure to do so could result
in shock/death or fire. If in doubt, seek advice from
Protect the power cord and plug from any physical
stress to avoid risk of electric shock.
Do not place heavy objects on the power cord. This
could cause electric shock or fire.
a registered electrician.
Cleaning
Do Not Remove Any Covers
Within the product are areas where high voltages may
present. To reduce the risk of electric shock do not remove
any covers unless the AC mains power cord is removed.
When required, either blow off dust from the product or
use a dry cloth.
Do not use any solvents such as Benzol or Alcohol.
For safety, keep product clean and free from dust.
Covers should be removed by qualified service
personnel only.
Servicing
No user serviceable parts inside.
Refer all servicing to qualified service personnel only. Do
not perform any servicing other than those instructions
contained within the User's Manual.
Fuse
To prevent fire and damage to the product, use only
1
PREFACE
Dear Customer:
Thank you for choosing the LTO DJM-4 3-Channel VCA-CONTROLLED DJ Mixer with Beat Counter, which is the
result of our LTO AUDIO TEAM's endeavours.
For the
LTO AUDIO TEAM, music and audio is more than a profession, it is a passion and an obsession!
We have, in fact, been designing professional audio products for a number of years in cooperation with many of the
world's major brands.
The LTO line represents unparalleled analogue and digital products made by musicians, for musicians. With our
design centres in Italy, the Netherlands, and the United Kingdom we provide you with world-class designs, while our
software development teams continue to develop an impressive range of audio specific algorithms.
By purchasing our LTO products you become the most important member of our LTO AUDIO TEAM. We would
like to share with you our passion for what we design and invite you to make suggestions, which will aid us in developing future products for you. We guarantee you our commitment for quality, continual research and development, and
of course the best prices.
The LTO DJM-4 is an extremely flexible 3-Channel VCA-CONTROLLED DJ Mixer with Beat Counter, configured
with three input channels. Each channel is equipped with a variety of key features including 3 phone/line inputs, 1
microphone input, intelligent dual auto beats per minute counter with time and beat sync. display, treble, middle and
bass EQ on each channel, crossfader curve etc..
We would like to thank all the people who made the LTO DJM-4 3-Channel VCA-CONTROLLED DJ Mixer with
Beat Counter possible, especially to our designers and LTO staff. It is their passion for music and professional
audio that has made it possible for us to offer you, our most important team member, our continued support.
Thank you very much
LTO AUDIO TEAM
2
TABLE OF CONTENTS
1. INTRODUCTION.....................................................................................................................................4
2. FEATURE LIST.......................................................................................................................................4
3. CONTROL ELEMENTS..........................................................................................................................5
3.1 The Top Cover
3.1.1 The CHANNEL Section
3.1.2 The MAIN OUT Section
3.1.3 The PFL Section
3.1.4 The LEVER METER Section
3.1.5 The BPM Section
3.2 The Front Panel
3.2.1 The KILL Function
3.2.2 The REVERSE Function
3.2.3 MIC IN Jack
3.2.4 CROSSFADER CURVE Control
3.2.5 The PHONE OUT Jack
3.3 The Rear Panel
3.3.1 AC Inlet and Fuse Holder
3.3.2 POWER Switch
3.3.3 GND Screw
3.3.4 The MAIN OUT
3.3.5 EFFECTS Send and Return
3.3.6 INPUT
4. TECHNICAL SPECIFICATIONS.............................................................................................................11
5. SYSTEM BLOCK DIAGRAM.................................................................................................................12
6. WARRANTY...........................................................................................................................................13
3
1. INTRODUCTION
What a great DJ mixer you have just bought. Your DJM 4 is packed with features such as digital beat counter, 3 turntable input, 3 line input, microphone input, 3 bands equaliser and replaceable cross-fader just to mention a few. Your
DJM 4 is VCA Controlled and it is very easy to operate. Please go through this Manual carefully and you will get the
best out of your DJM 4.
2. FEATURE LIST
8 Inputs: 3 phono and 3 line inputs, 1 microphone input, 1 return
Main outputs through RCA connectors, headphone output via 1/4" TRS jack
Gain Control and bass, middle, treble equaliser on each channel
Digital BPM (beats per minute) Counter
TALK control
SURROUND control
PFL switch
Crossfader curve Control
Accurate Led Meter (10-segment)
VCA assisted Faders
4
3. CONTROL ELEMENTS
3.1 The Top Cover
CHANNEL 1
CHANNEL 2
CHANNEL 3
LTO
R
DJM-4
3-CHANNEL VCA-CONTROLLED DJ MIXER WITH BEAT COUNTER
MIC
PHONO
LINE
PHONO
LINE
LINE
PHONO
LINE
LINE
MAIN OUT
LEVEL METER
MIN
GAIN
MAX
MIN
GAIN
MIN
MAX
GAIN
+10
MAX
MIN
OUT A
+7
MAX
+4
+2
+15dB
-30dB
+15dB
-30dB
TREBLE
-30dB
TREBLE
0
+15dB
TREBLE
LEFT
BAL A
-2
RIGHT
-4
-7
+15dB
-30dB
+15dB
-30dB
MIDDLE
-10
+15dB
-30dB
MIDDLE
MIDDLE
MAX
MIN
OUT B
-20
-30dB
BASS
+15dB
-30dB
PFL
BASS
+15dB
-30dB
PFL
CURVE
BASS
+15dB
OFF
PFL
CURVE
SURROUND ON
TALK
MAX
TALK ON
CURVE
SHARP
SHARP
SHARP
MID
MID
MID
SOFT
SOFT
SOFT
MIN
MAX
SURROUND
MIN
MAX
PFL
MAIN
PFL LEVEL
PFL MIX
STEREO
SPLIT
PFL MODE
TEMPO DIFFERENCE
TIME OFFSET
CH 2
CH 3
BEAT ASSIST
BEAT ASSIST
5
3.1.1 The CHANNEL Section
CHANNEL 1
1
-. The MIC to PHONO-LINE switch
The channel 1 is equipped with the MIC to PHONO-LINE
switch. This switch is used to select microphone input and
phono/line Input. When it is in the right position, you can
use the PHONO/LINE switch on the rear panel to input the
line signal to the phono input connector.
1
MIC
3
MIN
-. The EQUALISER control
Each Input Channel is provided with 3 bands equaliser:
Treble (4), Middle (5) and Bass (6) and you can adjust the
gain range of each from -30dB to +15dB.
GAIN
MAX
4
-. PHONO-LINE to LINE switch
2
This switch is available on input channel 2 and channel 3.
You should use the LINE position for all high level audio
signals such as CD Players, DAT, MD, etc.. You should use
the PHONO-LINE position to connect the turntables making
sure that the PHONO-LINE switch on the rear panel is on
PHONO position. With this switch (the one on the rear panel)
on LINE position, the Input Channel will accept a high level
audio signal.
3
-. The GAIN control
Via this knob you will adjust the input level. Do not turn this
control too much clockwise or you will overload the channel
and do not turn it too much counterclockwise or you will
generate background hiss.
PHONO
LINE
-30dB
+15dB
-30dB
+15dB
-30dB
+15dB
TREBLE
5
MIDDLE
6
BASS
9
PFL
CURVE
SHARP
MID
SOFT
7
-. The PROGRAM Fader
7
There is a Program Fader available on each input channel.
For optimum performance and operation the 3 Faders are
VCA (Voltage Control Amplifier) controlled. These Faders
adjust the overall level of the input channels.
CHANNEL 3
8
-. The CURVE control
Each input channel includes a 3-position switch denominated CURVE.
If you set the CURVE switch on SHARP position the level
will be changed quite quickly by the PROGRAM Fader even
if you move the Fader slowly.
If you set the CURVE switch in SOFT position, the level will
be changed much more slowly by the PROGRAM Fader
even if you move the Fader quickly.
2
PHONO
LINE
LINE
MIN
GAIN
MAX
-30dB
+15dB
-30dB
+15dB
TREBLE
If you set the CURVE switch in MID position you will combine the SHARP and SOFT configuration.
MIDDLE
-. The PFL button
9
This button is used to route the input signal of corresponding
channel to PFL section via pressing it.
6
-30dB
BASS
+15dB
8
3.1.2 The MAIN OUT Section
10
-. The OUT A control
The OUT A control is used to adjust the main level of the AMP
output on rear panel.
MAIN OUT
10
MIN
OUT A
-. The BAL A control
11
The BAL A control is used to adjust the stereo balance of the
AMP output on rear panel.
MAX
11
LEFT
BAL A
-. The OUT B control
12
The OUT B control is used to adjust the main level of the
BOOTH output on rear panel.
RIGHT
12
MIN
MAX
OFF
MAX
OUT B
13
-. The TALK control
13
When you speak through a connected microphone, the volume
of the reproduced music will be automatically reduced by the
mixer for better intelligibility of your voice. You can determine
yourself how much the volume of the music will be reduced
via this control. You can turn off the TALK function via this
button (14).
TALK
14
16
SURROUND ON
TALK ON
15
MIN
MAX
SURROUND
-. The SURROUND control
15
DJ Mixers are often used in quite inappropriate venues and
the positioning of the loudspeakers is not always optimal.
The Surround Control allow you to get a better transparency
and stereo image and will contribute to "clean" you mix.
-.The SURROUND ON switch
16
You can turn off the Surround function via this switch. You
can also run fast A/B comparison (with surround/without
surround) via this switch.
17
3.1.3 The PFL Section
18
When you connect a headphone to your DJM 4 you have the
chance of pre-listen the audio signal before the signal reach
the Main output.
-.LEVEL control
19
17
This knob will adjust the level of the headphone signal.
18
-.The PFL MIX control
When set the switch mode (19) in STEREO position, you can
fade between PFL and MAIN output.
-.MODE switch
19
This is a 2-position switch. When the switch is in STEREO
position, the PFL MIX control will fade between PFL signal and
MAIN output. When the switch is in SPLIT position, the PFL
MIX control has no influence on the PFL signal.
LEVEL METER
+10
+7
+4
+2
0
-2
3.1.4 The LEVEL METER Section
-4
-.LEVEL METER
20
-7
This 10 segments LED's Meter will monitor the output level.
7
-10
-20
20
3.1.5 The BPM Section
21
23
24
TEMPO DIFFERENCE
TIME OFFSET
CH 2
CH 3
BEAT ASSIST
BEAT ASSIST
22
25
This is a key and exclusive function in your DJM 4 mixer. What is the Beat Per Minute function/ It simply indicate
the "speed" of the music through a 3-digit display. The beats (per minute) of the music are automatically measured
by the BPM and then displayed on the 3-digit display. Of course the two BPM counters are available for CH 2 and
CH 3. Thanks to the BPM function you can mix more quickly songs with different tempo.
-. The TEMPO Display
21
This 3-digit display will show the tempo of CH 2 and CH 3. If the tempo changes the display will change accordingly.
-. The BEAT ASSIST switch
22
The Beat Assist button is available for CH 2 and CH 3 and it is below the Tempo display. Press the Beat Assist
button and you can manually regulate the beat. The Led nearby the Beat Assist button will show you whether
the function is active or not.
-. TEMPO DIFFERENCE Led segment
23
This 7 segments Led Meter will indicate the difference in tempo between the CH 2 and CH 3 or programs. If
the tempos on both channels are the same, the center LED will light. If the tempo of the music on channel 2 is
faster, the LED's on the left will start to light and vice-versa.
-. TIME OFFSET Led segment
24
This 7-segment Led Meter is positioned immediately below the Tempo Difference display. This display will indicate the synchronicity of the CH 2 and CH 3. When the two channels are synchronized, the center LED will
light. If LED's on the left will start to light, Channel 2 is getting out of sync and vice-versa.
-. The CROSSFADER
25
Through this crossfader you can fade in between CH 2 and CH 3. The Crossfader on your DJM 4 is VCA (Voltage Control Amplifier) controlled and it is User replaceable.
8
3.2 The Front Panel
26
27
KILL HOLD
BASS
KILL HOLD
MIDDLE
REVERSE HOLD
TREBLE
BASS
REVERSE TAP
KILL TAP
MIDDLE
KILL TAP
CROSSFADER
CURVE
MIC
IN
SMOOTH
28
PHONE
OUT
SHARP
29
3.2.1 The KILL Function
TREBLE
30
26
The KILL function is used to attenuate the three frequency bands: BASS, MIDDLE and TREBLE. There are
three modes: TAP, CENTER and HOLD.
There isn't KILL function in the CENTER position;
In TAP position, the function is triggered instantly and the switch will return to the center position as soon as
you release it.
In HOLD position, the function will be locked in the HOLD position. To cancel the effect you will need to push
back the switch in the center position.
The left and right KILL function are assigned to the CH 2 and CH 3 respectively. There is no KILL function for
CH 1.
3.2.2 The REVERSE Function
27
Like the KILL function, there are three modes for the REVERSE function (TAP, CENTER and HOLD). It is used
to invert the direction of the crossfader so that an immediate inversion of CH 2 and CH 3 will be achieved.
3.2.3 MIC IN Jack
28
This input will accept any unbalanced low impedance microphone. The functions of the microphone will be
controlled by the CHANNEL section on the Top Panel.
3.2.4 CROSSFADER CURVE Control
29
Via this knob you will adjust the crossfader curve. Please see (8) earlier in this Manual for further reference.
3.2.5 The PHONE OUT Jack
30
This input will accept a standard headphone with a 1/4" stereo jack.
9
3.3 The Rear Panel
32
34
35
36
33
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
WARNING: SHOCK HAZARD - DO NOT OPEN
AVIS: RISQUE DE CHOC ELECTRIQUE - NE PAS OUVRIR
POWER
MODEL
Apparaten skall anslutas till
jordat uttag nar den ansluts
till ett natverk
ON
BOOTH
AMP
OFF
SERIAL
GND
GND
SEND
TAPE
FROM PFL
RETURN
TO MAIN
LINE
PHONO
LINE
PHONO
GND
LINE
PHONO
L
Use only with a 250V fuse
R
AC INPUT
MAIN OUT
31
USA / Canada
100-120V
60Hz
Fuse:T500mAL
UK / Aust
240V
50Hz
Fuse:T315mAL
3.3.1 AC Inlet and Fuse Holder
INPUT 3
EFFECTS
EUROPE
210-240V 50Hz
RATED POWER CONSUMPTION: 25W
Fuse:T315mAL
37
PHONO
LINE
38
40
INPUT 2
PHONO
LINE
INPUT 1
PHONO
LINE
41 39
31
Use it to connect your DJM 4 to the Main AC with the supplied AC cord. Please check the Voltage available
in your Country and make sure the voltage is identical to the values marking on the product. Replace the fuse
with the same type by the qualified personnel only.
3.3.2 POWER Switch
32
This switch turns the Mixer ON and OFF.
3.3.3 GND Screw
33
GND is the supplementary grounding selection for other connected instruments.
3.3.4 The MAIN OUT
The AMP, BOOTH and TAPE outputs are RCA type connectors. Yes the same largely used in hi-fi and are low
impedance.
Through the AMP output (34), you can connect your DJM 4 to an amplifier, and the level will be controlled by
OUT A on the Top panel;
Through the BOOTH output (35), you can connect your DJM 4 to an additional amplifier and/or loudspeaker
system and the level will be controlled by OUT B on the Top panel;
Through the TAPE output (36), you can connect your DJM 4 to a tape recorder. The TAPE level is fixed, so you
should adjust the input level of the recorder.
3.3.5 EFFECTS Send and Return
You can send the PFL signal through the SEND (37) sockets to a signal processor such as reverb, equaliser,
etc.. Then from the same effect unit you bring the signal back into the DJM 4 via the RETURN (38) sockets
and the audio signal is routed into the MAIN output.
3.3.6 INPUT
- PHONO input (39): The three Channels feature PHONO inputs including RIIA preamplifier for turntable. PIN
(RCA) jacks shall be used to connect the turntable.
- LINE input (40): Through these RCA type sockets you can connect a CD player, an MD player or any other
high level device such as Tape Recorder, DAT, etc..
Important Notice: If you wish to connect LINE level devices into the LINE/PHONO input, make sure that the
LINE/PHONO switch (41) is on LINE position otherwise the sensitive RIAA preamplifier built-in in the Phono
input will be overloaded and will produce distortion.
10
4. TECHNICAL SPECIFICATIONS
INPUTS
Phono Inputs 1,2 and 3
40dB gain@1kHz,unbalanced
Line Inputs 1,2 and 3
0dB gain, unbalanced
Mic Input
40dB gain, servo-balanced
Return
0dB gain, unbalanced
Headphones
typically 125mW@ 1% THD
Main Out
max +21dBu
Booth Out
max +21dBu
Tape Out
typically 0dBu
Send
typically 0dBu
Stereo Bass
+15dB/
30dB@ 50Hz
Stereo Middle
+15dB/
30dB@2.5KHz
Stereo Treble
+15dB/
30dB@10KHz
OUTPUTS
GENERAL
Kill Bass
54dB@50Hz
Kill Middle
40dB@1KHz
Kill Treble
26dB@10KHz
Signal
to
Noise ratio(S/N)
>90dB(LINE)
70dB
Crosstalk
Distortion(THD)
3dB(LINE)
0.05%
Frequency Response
20Hz
Input Gain Adjustment
20KHz (
20dB
9dB (
2dB)
3dB)
POWER SUPPLY
Connector type
3
Main Voltage
USA/Canada100
pole IEC, grounded
Europe210
120V~, 60Hz
230V~, 50Hz
U.K./Australia240V~, 50Hz
Power Consumption
25watts
Fuse
95
210
120V~ : T500mAL
240V~ : T315mAL
DIMENSIONS and WEIGHT
Dimension
248(L)
Weight
2.9Kg (6.39lb)
11
245(W)
76.6(H)mm (9.8"
9.6"
3.0")
12
A
B
C
D
1
P
B
CHANNEL2(INPUT)
PHONO
LINE
B
R
L
R
2
CHANNEL3(INPUT)
PHONO
LINE
3
P
B
A
P
B
BPM
4
6
5
4
5
6
SN8P1707Q
6
3
2
4
3
2
1
5
5
1
6
3
2
1
4
5
6
3
2
1
4
3
2
1
6
6
A
5
5
L
4
4
P
3
1
3
R
A
2
L
2
1
P
D
C
P
D
C
P
D
C
4
GAIN
GAIN
GAIN
GAIN
GAIN
GAIN
LEVEL METER
12
11
10
7
8
9
12
11
10
7
8
9
12
11
10
7
8
9
TIME OFFSET
TEMPO DIFFERENCE
PHONE / LINE
B
A
PHONE / LINE
B
A
B
A
P
A
4
P
3
P
2
P
P
CHANNEL1(INPUT)
PHONO
LINE
P
1
MID
HI
5
3-BANDEQ
LO MID HI
3-BANDEQ
LO MID HI
3-BANDEQ
LO MID HI
3-BANDEQ
LO MID HI
3-BANDEQ
LO MID HI
3-BANDEQ
LO
5
5e
3c
4d
2b
1a
6
MIC INPUT
6
SEND FROM PFL
(EFFECTS)
BOOTH
(MAINOUT)
AMP
(MAINOUT)
TAPE
(MAINOUT)
5e
3c
4d
2b
1a
PHONESOUT
R
L
R
L
R
L
R
L
R
L
RETURNTO MAIN
(EFFECTS)
A3
DJM-4
7
Djm-4 DIGRAM.Sch
16-Apr-2003
Model No:
DJM-4 BLOCK DIGRAM
PFL LEVEL
Date:
File:
Size
Titel
PFL MODE
PFL MIX
( MAIN)
(PFL)
GAIN
GAIN
GAIN
GAIN
7
Sheet 1
Drawn By:
V1.0
8
of 1
TASY J.S.
Revision
8
A
B
C
D
5. SYSTEM BLOCK DIAGRAM
Voltage Controlled Amplifier
6. WARRANTY
1. WARRANTY REGISTRATION CARD
To obtain Warranty Service, the buyer should first fill out and return the enclosed Warranty Registration Card within
10 days of the Purchase Date.
All the information presented in this Warranty Registration Card gives the manufacturer a better understanding of
the sales status, so as to purport a more effective and efficient after-sales warranty service.
Please fill out all the information carefully and genuinely, miswriting or absence of this card will void your warranty
service.
2. RETURN NOTICE
2.1 In case of return for any warranty service, please make sure that the product is well packed in its original shipping
carton, and it can protect your unit from any other extra damage.
2.2 Please provide a copy of your sales receipt or other proof of purchase with the returned machine, and give detail
information about your return address and contact telephone number.
2.3 A brief description of the defect will be appreciated.
2.4 Please prepay all the costs involved in the return shipping, handling and insurance.
3. TERMS AND CONDITIONS
3.1
LTO warrants that this product will be free from any defects in materials and/or workmanship for a period
of 1 year from the purchase date if you have completed the Warranty Registration Card in time.
3.2 The warranty service is only available to the original consumer, who purchased this product directly from the
retail dealer, and it can not be transferred.
3.3 During the warranty service, LTO may repair or replace this product at its own option at no charge to you for
parts or for labor in accordance with the right side of this limited warranty.
3.4 This warranty does not apply to the damages to this product that occurred as the following conditions:
Instead of operating in accordance with the user's manual thoroughly, any abuse or misuse of this product.
Normal tear and wear.
The product has been altered or modified in any way.
Damage which may have been caused either directly or indirectly by another product / force / etc.
Abnormal service or repairing by anyone other than the qualified personnel or technician.
And in such cases, all the expenses will be charged to the buyer.
3.5 In no event shall LTO be liable for any incidental or consequential damages. Some states do not allow the exclusion or limitation of incidental or consequential damages, so the above exclusion or limitation may not apply to you.
3.6 This warranty gives you the specific rights, and these rights are compatible with the state laws, you may also
have other statutory rights that may vary from state to state.
13
SEIKAKU TECHNICAL GROUP LIMITED
No. 1, Lane 17, Sec. 2, Han Shi W. Road, Taichung, 401 Taiwan
http://www.altomobile.com Tel: 886-4-22313737
email: info@altomobile.com Fax: 886-4-22346757
All rights reserved to ALTO Mobile. Due to continued development in response to
customer feedback, product features, specifications and/or internal/external design may be
changed without prior notice. No photocopying, translation or reproduction of any part of this user
manual is allowed without prior written permission.Copyright c 2004 Seikaku Technical Group Limited.
NF01340-1.0