Mackie SP2400 Instruction Manual

AC Power Considerations

Each SP2400 draws an average of 6 amps of AC
line current (@ 120VAC) when fully loaded and
playing music with a relatively high crest factor.

Voltage Conversion

The SP2400 can be configured to operate at
115V AC or 230V AC. See Appendix C for instructions
on how to change the operating voltage configuration.

Thermal Considerations

IMPORTANT: The SP2400 is convection
cooled rather than fan cooled. This design

was chosen to avoid the requirement for
periodic air filter maintenance, and to keep the
insides of the SP2400 clean in dirty environments
(rather than blowing dirty, smoky air into it). Heat is
drawn away from the amplifiers by the heatsinks
and radiated through the cooling vents in the top
cover. When installing the SP2400, be sure to allow
sufficient air space around the top and rear of the
amplifier to allow adequate cooling for the
heatsinks. If installing in a rack,

rack space above and below the SP2400 for a vent,
and at least 6 inches behind the chassis to allow
proper ventilation.

leave at least one

If installing three or more SP2400s in a rack, use a
fan in the rack to move cool air in and warm air out of
the rack's enclosure. It may be necessary to provide
a cool air intake fan at the bottom of the rack, and a
warm air exhaust fan at the top (see Figure below).

Note: Though it is not required, it is
recommended that a warm air exhaust fan be used
when two SP2400s are installed in the same rack.

If the amplifier should overheat, a thermal switch
is activated that disengages the speaker outputs,
allowing the heatsinks to cool down. The

OVERLOAD

indicator on the front panel will also
light to show that a protection circuit has been
activated. Once the amplifier has cooled to a safe
operating temperature, the thermal switch resets
and reactivates the speaker outputs. If this should
occur, identify the cause of the problem and take
corrective action (i.e., provide better ventilation,
install a fan in the rack to move more air, make sure
the amplifier is not overloaded with too low of a
load impedance).

2U Exhaust Fan Panel

1U Vent Panel

1U Vent Panel

2U Vent Panel

(or Optional Intake Fan)

Cool Air

Intake

Cool Air

Intake

Cool Air

Intake

Cool Air

Intake

Cool Air

Intake

Hot Air

Exhaust

SP2400 – 15

4. Operation

SP2400 Quick Start

This isn’t a substitute for reading the entire
instruction manual, which is the only way to fully
understand how the SP2400 works. However, the
Quick Start provides a quick overview so you can
get the SP2400 set up and working right away.

Make sure the power switch is off while
setting up and making connections to the
SP2400.

External Switch Settings

• The Paging Mic and the Local Mic have +24 VDC

PHANTOM

down to activate the phantom power if you are
using condenser microphones.

• The Paging Mic and Local Mic also have

+40dB

position when microphones are connected to these
inputs.

• If you plan on connecting two or more SP2400s
together in a system with the
bus, use the
either the local Program Input source (switches up)
or a remote program source from the

IN/OUT

switches (1, 3, 5, 7) select the left inputs, and the
even-numbered switches (2, 4, 6, 8) select the right
inputs.

• If you’re using the SP2400 in a stereo configuration,
move the
a zone configuration planned, leave the

MONO

and right channels into a mono signal.

• For stereo operation, assign the same

ADDRESS
ADDRESS

one channel and to the Slave position on the other
channel). The front panel and remote control panels
will operate both amplifiers when they are assigned
to the same
select Program Input 1 with the Zone A control,
Program Input 1 is also selected in Zone B, routing
the Program Input 1 left signal to the Zone A
(Stereo Left) amplifier, and the Program Input 1
right signal to the Zone B (Stereo Right) amplifier.

• For zone operation, assign different

ADDRESS

panel and remote control panels will operate
independently for each amplifier and zone.

power switches. Move the switches

GAIN

switches. Leave the switches in the down

EXPANSION IN/OUT

LOCAL/REMOTE

bus (switches down). The odd-numbered

STEREO/MONO

switches down (default) to combine the left

setting to both amplifiers (set the
DIP switch #6 to the Master position on

AMP ADDRESS

settings to each amplifier. The front

switches to select

EXPANSION

switches up. If you have

STEREO/

AMP

AMP

. For example, if you

AMP

Internal Switch and Jumper Settings

Refer to “Internal Settings” on page 13 for more

information.

• Bus Assign switches are used to assign a
program input source to the balanced expansion
bus. There are four switches for each program input
source: Left (+), Left (–), Right (+), and Right (–).

CAUTION : Never assign more than one
program source to each of the four
expansion bus outputs.

• EQ Bypass allows you to bypass the 3-band EQ,
which is in the Input 1-4 signal path. EQ engaged is
the default setting.

• The amplifier can be configured for 8-ohm, 70V
(default), or 100V operation via eight jumpers on the
amplifier board.

Program Inputs

Connect any stereo line-level signal source to
the Program Inputs 1-4. If you have a music-on-hold
requirement, connect a continuous music source to

INPUT 1

can feed the signal connected to
telephone system.

(e.g., a jukebox), connect it to

AMP ADDRESS

priority.

for now (1K for the
adjusted later, if necessary.

. The

DIRECT OUTPUT

If you have a need for a priority Program Input

switch #7 UP to enable

Set the 3-band EQ controls to the “U” position

FREQ

jacks next to

INPUT 1

INPUT 4

control). These can be

INPUT 1

to the

. Move the

INPUT 4

Paging Mic Input

Connect a microphone to the
Use either the XLR connector, or the supplied
Phoenix-type connector. Set the

GAIN +40dB

Adjust the
the meter level is at the “0” mark. Set the
control so the meter indication is near the “0” mark
when speaking at an average level into the
microphone. See “Setting The Vox Threshold” on
page 19 for more information.

Set the 2-band EQ (
position. This can be adjusted later, if necessary.

switches to their appropriate positions.

MASTER VOLUME

LOW

PAGING MIC

PHANTOM

up/down buttons so

and

HIGH

and

GAIN

) to the “U”

input.

SP2400 – 16

Paging Mic Control

The

PAGING MIC CONTROL

provided to connect a manual paging switch.
Connect a normally-open switch between

ZONE A

(to page in Zone B only), or
(to page over the entire system). The voice­activated (
operates in both zones when the switch is off.

(to page in Zone A only),

VOX

) control for the Paging Mic still

connector is

GND

GND

and

GND

and

ZONE B

ALL CALL

and

Local Mic/Line Inputs

Connect a microphone to
(one for each zone), using the supplied Phoenix-type
connector, to use for a meeting room or other local
speaking requirements. Set the

GAIN +40dB

Select the
disengages the selected Program Source and
engages the

VOLUME
the “0” mark.

Note: The

MIC/LINE INPUTS
VOLUME
VOLUME

memory when the
OFF button is engaged). When an
selected, the

MIC/LINE INPUT

Set the
near the “0” mark when speaking at an average
level into the microphone.

Set the 2-band EQ (
position. These can be adjusted later, if necessary.

switches to their appropriate positions.

OFF

button on the front panel. This

MIC/LINE INPUT

up/down buttons so the meter level is at

MASTER VOLUME

is independent of the
setting for
setting for

MASTER VOLUME

GAIN

INPUTS 1-4
INPUTS 1-4

MIC/LINE INPUT

is stored in memory.
control so the meter indication is

MIC/LINE INPUT A or B

PHANTOM

. Adjust the

setting for the

. The

MASTER

is stored in

is selected (the

INPUT 1-4

setting for the

LOW

and

HIGH

) to the “U“

and

MASTER

MASTER

is

Ambient Mic Inputs

This is an optional connection, but can greatly
enhance the performance of the Paging Mic.
Connect the optional MT-3100 mic to the

MIC

input (one for each zone). This provides an
“ear” for the microprocessor to adjust the Paging
Mic gain to compensate for the ambient noise level
in the room. Use the supplied Phoenix-type
connectors to make these connections.

Note: Move the
enable the ambient mic. See page 20 for more
information on "Using the Ambient Mic."

AMP ADDRESS

AMBIENT

switch #8 UP to

Expansion In/Out

If you are connecting two or more SP2400s in a
system, use the
to distribute the Program Input sources assigned to
the Expansion Bus between SP2400s. The two 25­pin D-Sub connectors are in parallel (use one to
connect to the previous SP2400 and one to connect
to the next SP2400 in the chain).

EXPANSION IN/OUT

connections

REMOTE

You can connect one or more optional remote
controls (up to 10) to each zone on the SP2400 to
provide wall-mounted input select, program signal
volume control, and local mic volume control.

RS485

A PC can be connected to the RS485 port to
provide computer control for up to 16 SP2400s,
interconnected via their RS485 ports, using the
SPLinker Sound Palette Control software application.
If the PC doesn't have an RS485 serial port, you can
either install an RS485 interface card, or use an
RS232 serial port with an RS232-to-RS485 converter.

Two zones can be controlled with one wired
remote control by connecting the RS485 ports
between the two zones. (The RS485 ports are
connected internally, so an external connection
between the RS485 ports on a single SP2400 is not
necessary.) Each amplifier must have the same

AMP ADDRESS

control is connected, with one assigned as Master
and the other as Slave. Use the supplied Phoenix­type connectors to make these connections.

Note: Move the
DOWN for Master and UP for Slave.

as the amp to which the remote

AMP ADDRESS

switch #6

PRE OUT/AMP IN

These connections can be used to insert a signal
processor (i.e., graphic equalizer, compressor, etc.)
into the signal chain, or to feed the signal to additional
power amplifiers. If no external processor or external
amplifier is to be used, leave the U-shaped jumper in
place between the

PRE OUT

and

AMP IN

connectors.

OUTPUTS

Use the supplied two-conductor Phoenix-type
connectors with appropriate speaker wiring to
connect to the speaker or distributed speaker
system.

SP2400 – 17

Using INPUTS 1-4

Connect the program sources to Inputs 1-4.
These could include a CD player, tape deck, tuner,
satellite feed, TV audio, jukebox, or an audio feed
from a live band. All four program inputs use
unbalanced RCA connectors and accept stereo line­level signals.

Note: The Input Select buttons are labeled 1
through 4 on the front panel. The spaces below the
buttons are sized to accept 1/4" labels from the
Brother P-Touch Electronic Labeling System.
Professional-looking labels can be made to clearly
identify the program source connected to each
input (visit www.brother.com).

There are no individual volume controls for
Inputs 1-4. The SP2400 automatically adjusts the
volume for each input using an AGC circuit
(Automatic Gain Control). This provides the best
signal-to-noise ratio and insures that the volume
remains the same when you switch from one
source to another.

Only one Input source can be selected at a time.
When switching from one source to another, the
previous source fades out while the new source
fades in (digital crossfade), rather than abruptly
switching between the two.

In a zone configuration, move the

MONO

into a mono signal for each program source. Set the

AMP ADDRESS

allow independent control over each zone.

switches down to combine the stereo signal

switches to different addresses to

STEREO/

LOCAL or REMOTE

These switches are used to select the input
source for each of the four Program Inputs. Leave
the switches up to select the local input source
connected to the
Move the switches down to select the remote
signal coming from the
Each Program Input has two switches, one for the
left input and one for the right input.

PROGRAM INPUT

EXPANSION IN

connector.

connector.

Bus Assign

These internal switches are used if you have two
or more SP2400s connected together in a system
using the
the four program inputs can be individually assigned
to the
switches associated with each Program Input source
(see the Bus Assign Switch chart on page 13).

Caution: Never assign more than one program
source to each of the four expansion bus outputs.

EXPANSION IN/OUT

EXPANSION

balanced bus. There are four

connectors. Each of

INPUT 1 and the Direct OUTPUT

Input 1 provides a direct line-level output that
can be used for music-on-hold or other external
applications. Connect a continuous music source
(i.e., satellite feed, prerecorded background music,
multi-disc CD player) to Input 1 and connect the

DIRECT OUTPUT

jacks to the external destination.

INPUT 4 Priority

Normally, the four program inputs are non­priority inputs. However, if there is a jukebox or
other priority program source in the system,
Program Priority can be activated on Input 4 by
setting
signal appears at Input 4, it overrides the other
three inputs. When the signal stops, the SP2400
switches back to the previously selected input
source, fading it in smoothly.

AMP ADDRESS

switch #7 UP. When a

STEREO or MONO

The four program inputs accept stereo signals.
The SP2400 can be operated in a stereo configura­tion or a zone configuration. The
switches should be set to the up position for stereo
operation. Set the
same address to allow the front panel and remote
control panels to operate both amplifiers.

AMP ADDRESS

STEREO/MONO

switches to the

EXPANSION IN/OUT

These two 25-pin D-Sub connectors are used to
connect two or more SP2400s together so they can
share program sources. This is a true balanced bus
and transmits the left and right signal from each of
the four inputs over balanced lines. Refer to the
“Connections” section on page 12 for information
on wiring these connectors.

These connections allow a common program
source to be available to all the SP2400s in a
system. For example, prerecorded music that is
used for music-on-hold can also serve as background
music for an entire office building by setting the
internal bus assign switches for Input 1 to the up
position on the first SP2400. The music is then
available to Input 1 on all the SP2400s connected
via the

LOCAL/REMOTE

position (down).

REMOTE

different program source is connected locally to
Input 1 on one of the SP2400s in the above
example, both the common program source (the
remote prerecorded music) and the local program
source will be combined on Input 1 and can be
played simultaneously. Typically, a local program
source would not be connected to an Input which
has

EXPANSION IN/OUT

switches are set to the

Note: Switching the

doesn't disconnect the local input. If a

REMOTE

selected as the source.

connectors when their

LOCAL/REMOTE

REMOTE

switch to

SP2400 – 18

Using the 3-Band EQ

This equalizer is applied to the selected program
source from Inputs 1-4, whether it is a local source
or remote source (via the

This equalizer does not affect the paging mic or
the local
own 2-band EQ controls.

MIC/LINE INPUTS

EXPANSION IN/OUT

, which each have their

bus).

Using the Paging Mic

The paging mic is used to make announcements
over the system. If the paging mic is a condenser
mic or other type of mic that requires phantom
power, move the
position. Otherwise, leave them switched up.

The paging mic can be voice-activated and is
routed to both channels or zones. However, you have
the option of activating it manually with an external
switch. If you choose to use a switch for the paging
mic, you have the additional option of assigning the
paging mic to either Zone A or Zone B, or to both zones.

• For Zone A only, connect a (normally-open)
switch between the
the

PAGING MIC CONTROL

• For Zone B only, connect a switch between the

ZONE B
CONTROL

• For all zones in a system interconnected via the

EXPANSION
ALL CALL
CONTROL

• For maximum flexibility, connect three switches
to the
all three selections available.

turn down (duck, or attenuate) the music that is
playing over the system so the announcement can
be heard when using the VOX circuit. When an
announcement is over, the music gradually returns
to its original volume.

music 20 dB within 300 ms (milliseconds) of
detecting a signal on the paging mic. When the
signal on the paging mic stops, there is a 1500 ms
(1.5 second) timeout period to make sure the
announcement is over, and then the music ramps
up to its original volume over the next 2.5 seconds.

there is no timeout period after the announcement
ends. The moment you let go of the switch, the
music begins to ramp up to its original volume.

and

connector.

and

connector.

PAGING MIC CONTROL

The paging mic can be configured to automatically

The music ducks fairly rapidly, attenuating the

Note 1: When manually activating the paging mic,

PHANTOM

ZONE A

GROUND

bus, connect a switch between the

GROUND

switches to the down

and

GROUND

connector.

pins on the

pins on the

PAGING MIC

PAGING MIC

connector and have

pins on

Note 2: When the manual switch is off, the
voice-activated (
still operational. Ensure that the
threshold is set accordingly to prevent false
triggering of the paging mic input when using

PAGING MIC CONTROL

turn the
(fully clockwise) to defeat the VOX circuit. Note that
each zone has its own

PAGING MIC VOX

VOX

) control for the paging mic is

PAGING MIC VOX

switching. Alternatively,

control all the way up

PAGING MIC VOX

control.

Setting the GAIN

When a microphone is connected directly to the
paging mic input, the
set in the down position (for a mic-level signal). When
the paging mic is going through an external mixer,
sending a line-level signal to the paging mic input,
move the
a line-level signal only).

Adjust the
pressing the up/down buttons so the meter
indicates a level at the “0” mark. With all music
sources off, speak into the paging mic with a
normal voice. Adjust the
with a non-conductive alignment tool so that the
meter indication is near the “0” mark. This provides
the best signal-to-noise ratio for the mic, and
insures that the signal from the paging mic is strong
enough to trigger the

GAIN +40dB

MASTER VOLUME

GAIN +40dB

switch to the up position (for

PAGING MIC GAIN

VOX

circuit.

switch should be

control by

control

Setting the VOX Threshold

This control determines how strong the signal
from the paging mic must be to trigger the
circuit, which ducks the program source when an
announcement is made. Ideally, the threshold
should be set so it is sensitive enough to trigger the

VOX

circuit as soon as you begin speaking, but not
so sensitive as to be triggered by ambient sounds
around the microphone. Set the
control to the center position with a non-conductive
alignment tool to start. Turn the control counter­clockwise to lower the threshold (increase the
sensitivity) if the beginning of announcements are
getting clipped off. Turn the control clockwise to
increase the threshold (decrease the sensitivity)
should you experience false triggering due to
ambient noise around the microphone.

PAGING MIC VOX

VOX

Using the EQ

The paging mic has a 2-band equalizer for
adjusting the lows or highs on the microphone
signal. When the controls are set to “U” (unity), the
EQ has no effect on the signal.

SP2400 – 19

Using the AMBIENT MIC

The ambient mic is an optional accessory (MT-

3100) that is available for the SP2400, which is used
to sense the ambient noise level in the room. Set
the

AMP ADDRESS

ambient mic, otherwise leave the switch down.

The ambient mic provides an “ear” for the micro­processor to gauge the ambient noise in the room and
adjust the gain of the paging mic accordingly. When
the background noise is relatively quiet, the paging
mic gain is at its lowest level. If the background
noise is relatively loud, the paging mic gain is at its
highest level. If the background noise is some­where in between, the paging mic gain is midway
between its lowest and highest preset levels.

Ambient Mic Calibration and Placement

1. Connect the MT-3100 (or other microphone) to the

AMBIENT MIC

the ambient mic switch is on (

#8 up). Locate the ambient mic in an appropriate

position to pick up the ambient noise in the room. It

can be mounted on the ceiling or on a wall. Avoid

placing the ambient mic close to the speaker over

which the announcement is being made. Keep the

ambient mic away from a constant noise source, such

as a refrigerator or other mechanical device that emits

a continuous noise. The best placement is where the

mic can pick up an average representation of the

ambient noise level in the room.

Note: Each zone or channel must be calibrated

individually.

2. Turn off the SP2400, then turn it back on again while

pressing and holding the Input 2 button. This causes

the ambient mic preamp level to appear on the meter.

3. Establish the highest noise level that you would

expect to have in the room using a pink or white noise

source, or a music source. Input 1 is operational in this

mode to use as a music source, if desired.

4. Adjust the ambient mic preamp gain trim (located just

above the ambient mic connector on the rear panel,

through the unmarked hole) with a non-conductive

alignment tool until all the green LEDs on the meter are

lit. Insure that no yellow or red LEDs are lit, which runs

the risk of clipping the ambient mic preamp or ADC.

5. Press the “OFF” button when finished to return to

normal operation.

Paging Microphone Calibration Proce-

dure (when used with Ambient Mic)

1. Perform the “Ambient Microphone Calibration

Procedure” described above.

2. Switch the ambient mic OFF (

#8 down).

SP2400 – 20

switch #8 up to enable the

connector on the rear panel. Make sure

AMP ADDRESS

AMP ADDRESS

switch

switch

3. Adjust the

Up/Down buttons so the meter indicates a level at the
“0” mark.

4. Adjust the

go before feedback occurs while speaking into the
paging microphone.

5. Switch the ambient mic on (

#8 up).

6. Turn off the SP2400, then turn it back on again while

pressing and holding the “3” button.

7. Release the Input 3 button after a few seconds and

the third LED starts flashing slowly.

8. Use the front panel Up/Down buttons to set the lower

level of the paging mic (how loud it is with very quiet
background noise). It should be loud enough to be
heard clearly throughout the coverage area.

9. Press the “OFF” button and the level is stored. The

third LED starts flashing faster.

10.Use the front panel Up/Down buttons to set the upper

level of the paging mic (how loud it is with very loud
background noise). As a general rule, set this level as
high as it will go before feedback (at the "0" mark if
steps 3-4 above were followed).

11.Press the Input 3 button when finished to store the

level and return to normal operation.

12.Verify that the paging microphone’s volume is sufficient

to be heard over the background noise in the room.

Note: For best results, with the background noise
level at a minimum, the paging mic volume should be
approximately the same as the music volume.

13.If the paging microphone is not loud enough to be

heard over the background noise, verify that the
ambient mic is properly placed to pick up an accurate
representation of the background noise. If it is, it may
be necessary to readjust the lower and upper levels
for the paging mic gain (steps 6-11).

MASTER VOLUME

PAGING MIC GAIN

control by pressing the

control as high as it will

AMP ADDRESS

switch

Using the Local Mic/LINE INPUT

The

MIC/LINE INPUT A

each zone to connect a microphone for a speaker in
a conference room, or similar sound reinforcement
applications. If the local mic is a condenser mic,
move the

PHANTOM

Setting the GAIN

When a microphone is connected directly to the

MIC/LINE INPUT

set in the down position (for a mic-level signal).
When the mic is going through an external mixer,
sending a line-level signal to the input, move the
GAIN +40dB switch to the up position (for a line­level signal only).

, the

and B is provided for

switches to the down position.

GAIN +40dB

switch should be

Press the

INPUT

OFF

. Adjust the

button to select the

MASTER VOLUME

MIC/LINE

control by
pressing the up/down buttons so the meter
indicates a level at the “0” mark. With all music
sources off, speak into the mic with a normal voice.
Adjust the

MIC/LINE INPUT GAIN

control with a
non-conductive alignment tool so that the meter
indication is near the "0" mark. This provides the
best signal-to-noise ratio for the mic and insures
that its relative volume will be equivalent to the
program sources.

Distributed Speaker System

When using the SP2400 in a 70V or 100V
system, connect the speaker outputs directly to the
distributed system. The SP2400 can directly drive a
distributed system's speaker line without the need
for an output transformer. The SP2400 can supply
up to 200 watts into a 70V or 100V distributed
system. Make sure the taps on the speakers in
the system do not exceed a total of 200 watts.

Using the REMOTE Connection

Using the EQ

Each local
equalizer for adjusting the lows or highs on the
microphone signal. When the controls are set to
“U” (unity), the EQ has no effect on the signal.

MIC/LINE INPUT

has a 2-band

Using the PRE OUT/AMP IN Connections

The

PRE OUT

and

AMP IN

connectors are
provided to give you more flexibility in your system
design. The SP2400 is shipped with U-shaped
jumpers installed between the

IN

jacks. This routes the signal from the output of

PRE OUT

and

AMP

the preamplifier stage to the input of the amplifier
stage.

This also provides a point in the signal chain to
insert an external signal processor. Simply connect
the line-level signal from the

PRE OUT

jack to the
input of the processor, and connect the line-level
output from the processor to the

AMP IN

jack on

the SP2400.

Another option that is available is to connect
another amplifier into the system. Simply use a
Y-cord at the
between the

PRE OUT
AMP IN

jack and the input jack on an

jack to split the signal

external amplifier.

LEFT and RIGHT OUTPUTs

The amplifier outputs on the SP2400 can be
used with an 8-ohm impedance load, or to directly
drive a 70V or 100V distributed system (also called
constant-voltage systems).

Direct Speaker Connection

If the SP2400 is not being used in a distributed
speaker system, you can reconfigure the amplifiers
to drive an 8-ohm load. Each amplifier can provide
up to 250 watts into an 8-ohm load. See the
"Internal Settings" section on page 14 for
instructions on how to reconfigure the amplifiers.

The optional SP2400 Remote Control (SP-41R)
provides Input Selection and Master Volume control
for each amplifier or zone. The Remote Control can
be mounted in a standard double-gang electrical
box and covered with a Decora®-style faceplate.

3
0
3
6

9
15
30
55

Connecting One or More Remote Controls

Each Remote Control affects only the zone to
which it is connected. Up to ten remote controls
may be connected to each zone simultaneously.
This allows controls to be conveniently placed.
Each control will interact with the SP2400, and all
controls will reflect the current source and level
settings. Note that the remote control indicates the
gain setting and not the actual signal level in real
time. In addition, the SP2400 provides a method for
controlling two independent zones using a single
Remote Control by assigning them to the same

AMP ADDRESS

The maximum distance between the remotes
and the SP2400 varies, depending on the type of
cable selected and the number of remote controls
used. Typically, a lower wire gauge and cable
capacitance allow longer distances. See the instruc­tions with the remote control for more information.

(see next section).

SP2400 – 21

Using the RS485 Connection

Each amplifier is equipped with an
connection. These connectors are linked internally,
so if both amplifiers have the same
assignment, the Input Selection and

VOLUME

assigned to the same zone. One side must have

AMP ADDRESS

(up), and the other side in the Slave position (down).

two SP2400s by connecting the amplifiers together
with the
both amplifiers are assigned to the same zone
(

AMP ADDRESS

Master and the other Slave, and that no other
amplifiers are connected via the
the same

operate both amplifiers that are assigned to the
same zone.

ADDRESS

change is made to the
the SP2400 off for five seconds, then turn it back
on again for the new settings to take effect.

buttons track each other, since they are

switch #6 in the Master position

The same thing can be accomplished between

RS485

connection. Again, be sure that

switches 1-5), one is configured as

AMP ADDRESS

In this way, you can have one Remote control

Note: The microprocessor polls the

switch when it initializes at power-up. If a

.

AMP ADDRESS

Using the SPLinker Sound Palette

Controller

The RS485 connection can also be used to
connect the SP2400 to a computer loaded with the
SPLinker software application. The PC-compatible
computer must have an RS485 port to properly
connect to the SP2400. It may be necessary to
install an RS485 interface card, or use an RS232
port with an RS232-to-RS485 converter.

RS485

AMP ADDRESS

MASTER

RS485

port with

AMP

switch, turn

The SPLinker is a PC-based graphical interface to
provide real-time monitoring and control for up to 32
zones. It provides individual program source
selection and volume control for each zone. Select
boxes are located at the bottom of each zone for
selecting multiple zones. All selected zones can
then be modified at the same time in the Multiple
settings box located on the right-hand side of the
screen.

Using a 3rd Party Control System

The

RS485

connection can also be used to
interface with common third-party control systems.
Contact the third-party provider or Mackie Industrial
Technical Support to determine if your control
system is compatible with the SP2400.

Upgrading the Software

From time to time, Mackie Industrial will release
upgrades for the internal operating software in the
SP2400. This can be downloaded from our website
(www.mackieindustrial.com) to a PC-compatible
computer. Use the serial port on the computer to
connect to internal connectors on the SP2400's
CPU boards to transfer the data to the on-board
flash memory. Instructions will be provided when
upgrades are available.

SP2400 – 22

5. Specifications

SP2400 Block Diagram

L

DIRECT

OUTPUT

R

L

INPUT 1

R

L

INPUT 2

R

L

INPUT 3

R

L

INPUT 4

R

+24VDC

PAGING MIC

+24VDC

MIC/LINE

INPUT A

+24VDC

AMBIENT MIC

(ZONE A)

+24VDC

MIC/LINE

INPUT B

+24VDC

AMBIENT MIC

(ZONE B)

1

PHANTOM

2

3

1

3

PHANTOM

1

3

PHANTOM

1

3

PHANTOM

1

3

PHANTOM

1

3

GAIN

+40dB

GAIN

+40dB

GAIN

+40dB

GAIN

+40dB

GAIN

+40dB

GAIN

+40dB

GAIN

GAIN

INTERNAL

TRIM

GAIN

INTERNAL

TRIM

LO

80

ADC

LO

80

ADC

VOX

+

—

HI

12K

HI

12K

+

—

+

—

BUS

ASSIGN

+

—

+

—

BUS

ASSIGN

+

—

+

—

BUS

ASSIGN

+

—

+

—

TO EXPANSION I/O

TO µP

TO µP

BUS

ASSIGN

+

TO EXPANSION I/O

—

+

FROM

+

EXPANSION

—

I/O

—

+

FROM

+

EXPANSION

—

I/O

—

+

—

TO EXPANSION I/O

+

—

+

FROM

+

EXPANSION

—

I/O

—

+

FROM

+

EXPANSION

—

I/O

—

+

—

TO EXPANSION I/O

+

—

+

FROM

+

EXPANSION

—

I/O

—

+

FROM

+

EXPANSION

—

I/O

—

+

—

TO EXPANSION I/O

+

—

+

FROM

+

EXPANSION

—

I/O

—

+

FROM

+

EXPANSION

—

I/O

—

+

TO EXPANSION I/O

—

BUS

ASSIGN

MIC
+ —

ZONE A
ZONE B

ALL CALL

GND

TO ZONE B

PAGE MIC
SWITCH
CONTROL

12K

HI80LO

LOCAL/REMOTE

LOCAL/REMOTE

LOCAL/REMOTE

LOCAL/REMOTE

LOCAL/REMOTE

LOCAL/REMOTE

LOCAL/REMOTE

LOCAL/REMOTE

STEREO/
MONO

STEREO/
MONO

STEREO/
MONO

STEREO/
MONO

PAGING
MIC VOX

PAGING
MIC VOX

(TO µP)

(TO µP)

ATTENUATOR

CONTROLLED
ATTENUATORS

CONTROL
(FROM µP)

DIGITALLY

VOX

ACTIVATION

VOX

ACTIVATION

TO ZONE B

TO ZONE B

TO ZONE B

TO ZONE B

TO ZONE B

WOODINVILLE REDMOND

TO µP

TO µP

MACKIE INDUSTRIAL
SP2400
BLOCK DIAGRAM
(#01.02.01.DF)

MACKIE

INDUSTRIAL

PROGRAM EQ

MID FREQ

LO

80

ZONE A
AMP IN

12K

HI

BYPASS

OVERLOAD

J6
EQ

FROM µP

V+

V—

V+

V—

–15VDC (w/J2 INSTALLED)

INPUT 4 RIGHT (+)

INPUT 3 RIGHT (–)

INPUT 2 RIGHT (+)

INPUT 1 RIGHT (–)

–15VDC (w/J2 INSTALLED)

INPUT 4 RIGHT (+)

INPUT 3 RIGHT (–)

INPUT 2 RIGHT (+)

INPUT 1 RIGHT (–)

CONTROLLED
ATTENUATOR

FROM
TEMP

SENSOR

(ON HEATSINK)

PAGING MIC (+)

INPUT 4 LEFT (+)

INPUT 3 LEFT (–)

GROUND

INPUT 2 LEFT (+)

INPUT 1 LEFT (–)

PAGING MIC (+)

INPUT 4 LEFT (+)

INPUT 3 LEFT (–)

GROUND

INPUT 2 LEFT (+)

INPUT 1 LEFT (–)

DIGITALLY

N/C

N/C

3

0

3

6

9

15

30

55

J4

INSERT

(INTERNAL

FOR OPTIONAL

DSP CARD)

PROTECTION

70V/100V

EXPANSION IN

13

25

14

1

13

25

14

1

EXPANSION OUT

ADC

8Ω

+15VDC (w/J3 INSTALLED)
PAGING MIC CONTROL
PAGING MIC (–)
INPUT 4 RIGHT (–)
INPUT 4 LEFT (–)
GROUND
INPUT 3 RIGHT (+)
INPUT 3 LEFT (+)
INPUT 2 RIGHT (–)
INPUT 2 LEFT (–)
GROUND
INPUT 1 RIGHT (+)
INPUT 1 LEFT (+)

+15VDC (w/J3 INSTALLED)
PAGING MIC CONTROL
PAGING MIC (–)
INPUT 4 RIGHT (–)
INPUT 4 LEFT (–)
GROUND
INPUT 3 RIGHT (+)
INPUT 3 LEFT (+)
INPUT 2 RIGHT (–)
INPUT 2 LEFT (–)
GROUND
INPUT 1 RIGHT (+)
INPUT 1 LEFT (+)

TO µP

ZONE A

PRE OUT

LEFT/ZONE A

OUTPUT
+

—

SP2400 – 23

SP2400 Specifications

Power Amplifier Section

Continuous Sine Wave Average Output Power, both channels
driven:

200 watts per channel into 8 ohms from 20Hz to 20kHz, with no
more than 0.01% THD

100V rms per channel into 50 ohms from 20Hz to 20kHz, with no
more than 0.1% THD (J2/J3 in 100V position)

70V rms per channel into 25 ohms from 20Hz to 20kHz, with no
more than 0.1% THD (J2/J3 in 70V position)

Frequency Response

20Hz to 20kHz (+0, –0.5 dB)

Distortion

THD: < 0.01% @ rated output into 8 ohms

Signal-To-Noise Ratio

> 90 dB below rated power into 8 ohms
> 100 dB (A-weighted) below rated power into 8 ohms

Channel Separation

> 80 dB @ 1kHz

Amp Input Impedance

20K ohms

Input Sensitivity

+5 dBu (1.37V rms) for rated power into 8 ohms

Gain

27 dB (8-ohm position)
27 dB (70V position)
30 dB (100V position)

Maximum Input Level

12 volts P-P (+15 dBu)

Rise Time

< 5 µS

Slew Rate

> 17 V/µS

EQ

3-Band Program EQ:

High Shelving: ±15 dB @ 12kHz

Mid Peaking: ±15 dB with sweepable frequency

(250Hz to 8kHz)

Low Shelving: ±15 dB @ 80Hz

2-Band Mic EQ:

High Shelving: ±12 dB @ 12kHz

Low Shelving: ±12 dB @ 100Hz

General

Power Consumption

700 watts with musical program, 8 ohms per side
800 watts maximum

Phantom Power

24 VDC

AC Line Voltage

115VAC, 60Hz
230VAC, 50Hz

Fuse Rating

115V 8A Slow Blow, 250V
230V 4A Slow Blow, 250V

Dimensions

Height: 3.5" (88mm)
Width: 19" (483mm)
Depth: 16.7" (424mm)
Weight: 40 lbs. (18.1kg)

Accessories

MT-3100 Ambient Noise Sensing Microphone
SP-41R Remote Control

Preamplifier Section

Input Levels

Program Inputs: –10 dBu to +10 dBu for

Paging Mic Input: –52 dBu to +4 dBu
Local Mic Input: –52 dBu to +4 dBu

Maximum Input

Program Inputs: +15 dBu
Mic Inputs: +15 dBu

Maximum Output at Pre Out

+10 dBu

Stereo Separation

> 45 dB at 1kHz

SP2400 – 24

maximum output level
with internal AGC

Disclaimer

Mackie Industrial continually engages in research
related to product improvement, new materials, and
production methods. Design refinements are
introduced into existing products without notice as
a routine expression of that philosophy. For this
reason, any current Mackie Industrial product may
differ in some respect from its published description,
but will always equal or exceed the original design
specifications unless otherwise stated.

Mackie Industrial and Sound Palette are
trademarks or registered trademarks of Mackie
Designs Inc.

All other brand names mentioned are trademarks
or registered trademarks of their respective holders,
and are hereby acknowledged.

© 2001 All Rights Reserved.
Mackie Industrial.
Printed in the U.S.A.

6. Service Information

In the event that your SP2400 should require

servicing, please follow these instructions:

1. Call Mackie Industrial Tech Support at 1-888-337­7404, 8 am to 5 pm PST (Monday-Friday), to verify
the problem and obtain a Return Authorization (RA)
Number. Be sure to have the serial number of the
unit when you call. You must have a Return
Authorization Number in order to obtain warranty
service at the factory or at an authorized service
center.

2. Pack the unit in its original packaging. This is very
important. Mackie Industrial is not responsible for
any damage that occurs during shipping due to
non-conventional packaging. Original packaging
helps to minimize the possibility of shipping
damage.

3. Include a legible note stating your name, return
shipping address, (no P.O. boxes), daytime phone
number, Return Authorization Number, and a
detailed description of the problem, including how
we can duplicate it.

APPENDIX A: Default Settings

Control Setting

LOCAL/REMOTE UP (LOCAL)

STEREO/MONO DOWN (MONO)

PAGING MIC

PHANTOM UP (OFF)

GAIN +40dB UP (0dB)

GAIN CENTER

LOW CENTER (FLAT)

HIGH CENTER (FLAT)

ZONE A ZONE B

AMP ADDRESS 10000000 01000000

MIC/LINE INPUT

GAIN CENTER CENTER

LOW CENTER (FLAT) CENTER (FLAT)

HIGH CENTER (FLAT) CENTER (FLAT)

PHANTOM UP (OFF) UP (OFF)

GAIN +40dB UP (0dB) UP (0dB)

MIC VOX DOWN (OFF) DOWN (OFF)

PROGRAM EQ

LOW CENTER (FLAT) CENTER (FLAT)

MID CENTER (FLAT) CENTER (FLAT)

FREQ CENTER (1kHz) CENTER (1kHz)

HIGH CENTER (FLAT) CENTER (FLAT)

INTERNAL BUS
ASSIGN (S1/S2) OFF

NOTE: All SP2400s sold in the U.S. and Canada
are configured for 115V AC line input and 70V
speaker output. All units sold outside the U.S. and
Canada are configured for 230V AC and 100V
speaker outputs. Please confirm your configuration
prior to installation.

4. Write the Return Authorization Number in BIG
BOLD PRINT on the top of the box.

5. Ship the unit to us. We suggest insurance for all
forms of cartage. Ship to this address:

Mackie Industrial

Service Department

16140 Wood-Red Road NE, Suite 5

Woodinville, WA 98072

SP2400 – 25

APPENDIX B: Button Modes

SP2400 Button Modes

Press 1 on Power Up:

• Press and hold the Input 1 button while powering up the SP2400.

• Release the Input 1 button and the Input 1 LED blinks.
This resets the AGC for all four inputs to the default setting (–5 dBu).

• Press the Input 1 button again and the OFF LED lights. This indicates that the

AGC circuit is turned off.

• Press the Input 1 button again and the OFF LED turns off. This indicates that the
AGC circuit is turned on.

• Press the OFF button to save the settings and return to normal operation.

Press 2 on Power Up:

• Press and hold the Input 2 button while powering up the SP2400.

• Release the Input 2 button. The Ambient Mic Preamp gain is indicated on the LED meter.

• Use this mode to calibrate the ambient mic (see procedure on page 20).

• Press the OFF button to return to normal operation.

Press 3 on Power Up:

• Press and hold the Input 3 button while powering up the SP2400.

• Release the Input 3 button. The lowest Paging Mic level is indicated on the LED meter.

• Use the Up/Down buttons to adjust the lowest Paging Mic level.

• Press the OFF button. The highest Paging Mic level is indicated on the LED meter.

• Use the Up/Down buttons to adjust the highest Paging Mic level (see procedure on page 20).

• Press the Input 3 button to save the settings and return to normal operation.

AGC Reset

Ambient Mic Preamp Metering

Paging Mic Level Adjustment

Press 4 on Power Up:

• Press and hold the Input 4 button while powering up the SP2400.

• Release the Input 4 button. The LEDs on the front panel indicate the firmware version in binary.

• The Input 1-4 LEDs indicate the digit to the left of the decimal point, and the LED meter indicates

the digit to the right of the decimal point.

• For example, the following illustration indicates version 1.7.

• Press the OFF button to return to normal operation.

Firmware Version

3 LED pairs lit
111 (in binary) = 7 (in decimal)

Version 1.7

SP2400 – 26

Y

Y

APPENDIX C: Voltage Conversion

CAUTION: These servicing instructions are for use by qualified personnel only. To avoid electric
shock, do not perform any servicing other than that contained in the Operating Instructions
unless you are qualified to do so. Refer all servicing to qualified service personnel.

the power is off and the power cord disconnected

inside of the SP2400.

before removing the top cover to gain access to the

JUMPER INSTALLED FOR 115V

Make sure

RISK OF FIRE! REPLACE WITH FUSE AS MARKED

BLUE

R3

R4

R6

R5

R1

MACKIE DESIGNS. ™

© 2000

D1

+

K1

J12

D2

F1

055-286-00 REV:__
SP2400:SOFT START

4A SB 250V

C2

R2

J14

J11

J5

J8

J3

J1

YELLOW

YELLOW/RED

BLACK

BLACK/RED

YELLOW

ELLOW/RED

BLACK

BLACK/RED

J13

J10

J6

J9

J7

J4

J2

C3

BROWN

JP1

C1

®

SP2400: 115V AC CONFIGURATION
(8A, 250V SLOW BLOW FUSE INSTALLED IN IEC SOCKET)

REMOVE JUMPER FOR 230V

YELLOW

ELLOW/RED

BLACK

J13

J10

J7

J6

J9

C3

BROWN

JP1

RISK OF FIRE! REPLACE WITH FUSE AS MARKED

BLUE

R3

R4

R6

R5

J12

D1

+

D2

K1

F1

4A SB 250V

C2

J14

J11

J5

R2

J8

YELLOW

YELLOW/RED

BLACK

BLACK/RED

J4

J2

C1

®

R1

MACKIE DESIGNS. ™

© 2000

055-286-00 REV:__
SP2400:SOFT START

J3

J1

BLACK/RED

SP2400: 230 VAC CONFIGURATION
(4A, 250V SLOW BLOW FUSE INSTALLED IN IEC SOCKET)

SP2400 – 27

SP2400 Music Controller

Mackie Industrial

16220 Wood-Red Rd. NE • Woodinville, WA 98072 • USA

888/337-7404 • Outside the U.S.: 425/487-4333

Fax: [phone] • www.mackieindustrial.com