Dayton MA1240a User Manual

TWELVE CHANNEL
MULTI-ZONE
AMPLIFIER

Model: MA1240a User Manual

Thank you for purchasing the Dayton Audio® MA1240a Twelve Channel Multi-Zone Amplifier. The versatility of the
MA1240a makes it the perfect choice for almost every type of custom multi-room audio system. Its tabletop or rack­mountable design allows it to be integrated easily into high-end whole house audio systems.

FEATURES:

• 12 channels (6 stereo zones) in one convenient enclosure

• Stable Class AB design delivers superior audiophile sound
quality and performance

• Independent and bus inputs provides unparalleled flexibility

• Bridgeable channel outputs provide additional power
when needed

• Independent channel gain controls allow the output of
each speaker to be perfectly matched

• Manual, auto, or triggered on/off for integration into any
automated system

• Multi-stage protection circuitry for reliability and easy
troubleshooting of audio system

• Installer-friendly setup and connections

• Can be converted easily between rack-mount and
tabletop configurations

• Heavy-duty steel chassis with brushed aluminum faceplate

• Switchable 115/230V input voltage

INSTALLATION:

Dayton Audio amplifiers are designed to help deliver a great audio experience. However, where you place the amplifier can
have a large effect on the performance you receive, and the life of the unit. If you are not rack-mounting the amplifier, posi­tion it with all feet resting on a solid level surface. Be sure that the amplifier is in a well-ventilated area and DO NOT install
the amplifier near a source of heat or in an extremely humid or wet location.

CAUTION: All connections and switching must be done with the amplifier’s power switch positioned to ‘Off’. Connect the
power cord last to be sure that the amplifier is off during all of your connections and set up.

FRONT PANEL:

1. Master Power Switch / Indicator LED

Front panel pushbutton power switch turns the amplifier
on and off. When the switch is on and the indicator LED
is red, the amplifier is in standby mode. The remote turn
on switch (located on the rear) is either in the “trigger”
or “auto” position. When the LED is blue, the amplifier is
fully active. The master power switch will turn off the am­plifier no matter which power mode has been selected.

2. Zone Status Indicators

Each pair of channels or zones has a bi-color LED to

Fuse:T8AL 250VAC FOR 115VAC 60Hz
Fuse:T4AL 250AVC FOR 230VAC 50Hz

Date Code:

indicate its operational status. These indicators provide quick
and easy troubleshooting of the system. If the circuitry deter­mines that a channel must be shut down due to excessive
heat or low impedance (a short), only the channels that are
affected will be turned off causing the zone LED to turn red.
The remaining zones will continue to operate and maintain a
blue LED status. Once the condition has been corrected for
the zone in question, the status LED will return to blue.

Note: When the power LED is red and the zone status LEDS
are not lit (off), indicates the unit is in standby mode.

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REAR PANEL:

3. BUS Line Inputs / Outputs

The MA1240a has two common or BUS inputs that
receives audio signals from standard line-level audio
sources and sends them to any or all channels. The BUS
line outputs are direct feed-through to allow the BUS
inputs to be fed to other amplifiers. Be sure to use high
quality RCA cables that feature low impedance, shielding
and high quality connectors.

4. Remote Turn-On Switch

This switch selects the turn-on stimuli that will put the ampli­fier in ready mode. “Trigger” setting relies on 3-30V AC/DC
voltage going into the trigger input to activate the amplifier.
“Auto” setting senses a signal on the RCA line-level inputs
and automatically puts the amp in ready mode. “On” setting
puts the amp constantly in ready mode so that it can be
controlled by the master power switch on the front panel.
In “Auto” mode, the amplifier will take approximately 15
minutes to return from ready to standby mode.

5. Trigger Input / Output

The trigger input is a handy feature when connecting the
amplifier to an automated audio system. The 3.5mm mini­plug jack will accept a 3-30V AC/DC output from another
device, or from a separate power supply. When the trigger
input is energized, the amp turns from standby to ON mode.
When using the MA1240a with a receiver without a trigger
output, the voltage can come from a 12V wall wart (3.5mm
tip-positive connector) plugged into the receiver’s switched
outlet and the trigger input. The MA1240a can also provide
an output trigger voltage (12DC @500mA max.) to turn on
and off other devices in the audio system. When the ampli­fier turns off (standby mode), the voltage will drop to zero.

Note: Remember there is a delay of approximately 15
minutes before the amplifier goes to standby when using
the “Auto” turn-on mode.

6. Channel Gain Control

Each channel has its own independent level adjustment.
This allows the output level of each speaker to be per­fectly matched to its area. It can also be used to limit the
maximum audio level in a certain area.

7. Bridging Switch

By simply flipping a single switch, two channels can be
combined to increase the total power output. This is helpful
when extra power is needed in certain areas.

Note: The minimum impedance for bridged channels is 8
ohms. Also, please observe the proper speaker wiring when
bridging channels. Input selection and volume settings for
bridged channels will be controlled by the left channel. “BR”
is bridged mode and “ST” is non-bridged or stereo mode.

CAUTION: Only change switch positions when the
amplifier is turned off.

8. Input Selection Switch

Each channel is capable of delivering the source from
many inputs. The three main inputs are BUS 1, BUS 2
and LINE IN. The selection for these inputs is done via
the Input Selection switch associated with each channel.
Select the desired source input. Set the Input Selection
switch to BUS 1 (will play source connected to the BUS
1 input), BUS 2 (will play source connected to the BUS
2 input) or LINE IN (will play source connected to that
channel’s LINE IN).

CAUTION: Only change switch positions when the
amplifier is turned off.

CLOSE UP OF CONNECTIONS

9. Speaker Output Terminals

The MA1240a uses high quality Phoenix style connectors
for the speaker connections. Use 14-18 gauge stranded
two-conductor loudspeaker wire. Ensure that at least
2 inches of each conductor are separated. Strip away
¼ inch of insulation from each conductor. Connect the
appropriate conductor to each screw terminal, observing
correct polarity. Also, please observe proper speaker wir­ing when bridging channels.

10. Individual Channel Input

All twelve channels have their own dedicated input that
allows the connection of audio sources in addition to
the common BUS inputs. This is useful when using the
MA1240a with an audio matrix switcher.

11. AC Voltage Switch

The unit is set at the factory for 115V U.S. operation; simply
connect the included IEC power cord to your wall outlet.
For 230V operation, move the voltage selector switch to the
230V position. When operating at 230V the internal fuse
located in the IEC socket should also be changed. In most
230V applications a separate power cord will be required
and is not included.

12. IEC Power Connector

The unit comes with an IEC jack that permits removal of
the AC power cord. This allows the flexibility of changing
the power cord for different countries. The IEC socket
also houses the main fuse holder. Plug the power cord
supplied with the amplifier into the amplifier and wall
outlet or appropriate surge protector.

CAUTION: DO NOT plug the amplifier’s power cord into
a switched outlet, such as what is provided on some Sur­round Receivers. If you wish to have the amplifier turn on
when the Receiver is powered up, use one of the power
modes, such as Trigger or Auto.

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TYPICAL 6-ROOM INSTALLATION

NOTES ABOUT HUM:

While the MA1240a has been designed to minimize the possibility
of hum in the audio system, it is still possible that a hum will oc­cur in rare circumstances. Its safety grounding can create a path
for small amounts of 60 Hz energy to travel through the line-level
audio system. Although not dangerous, this energy can cause
diffi culty with the auto signal sensing circuit, and at the very least
will interfere with the quiet enjoyment of your system. The fi rst
course of action should be trying to make sure that all of the audio
components are connected to either the same electrical outlet, or
at least into the same circuit branch. Next, cable TV systems are
notoriously the culprit, so be sure to try disconnecting all coaxial
feeds that are connected to the system. If this solves the problem,
install a coaxial line isolator and reconnect the system. In the very
worst case, a line-level audio isolator/transformer connected to the
line-in of the amplifi er will usually solve the problem.

Rated Power Output: 40 watts per channel RMS at 8 ohms
Bridged Power Output: 80 watts per channel RMS at 8 ohms

(8 ohm minimum)

Input Sensitivity:
Input Impedance: 18K ohm
Frequency Response: 5 Hz to 72 kHz
Distortion: .005% THD 20 Hz-20 kHz @ 30W (8 ohm)
Distortion (Bridged): .010% THD 20 Hz-20 kHz @ 80W (8 ohm)
Channel Crosstalk: 80 dB
Signal to Noise Ratio: 105 dB A-weighted
Effi ciency: 63%
Power Requirements: 115/230 VAC, 60 Hz/50 Hz
Stand-By Power Rating: 115V, 0.264W *
Auto Turn-On Sensitivity: 13.7mV
Dimensions: 16.7” W x 4” H (including feet) x 14.25” D
Weight: 33 lbs.

SPECIFICATIONS:

380 mV for full output with all level controls at max.

* The MA1240a complies with the ENERGY STAR and CE EuP directive.

IMPORTANT SAFETY INSTRUCTIONS

To reduce the risk of electric shock, do not remove cover. No user serviceable parts inside. Refer
servicing to qualifi ed personnel. To reduce the risk of fi re and shock do not expose unit to rain or
moisture. The unit should be connected to an earth grounded AC electrical socket. The unit should
be operated in a well ventilated area. Minimum clearance is 2 inches from the ventilation openings.

Note: Unit is set at the factory for 120V operation. Be sure to change the fuse (4A rating) before
switching to 230V operation.

Dayton Audio products are constructed by industry experts, and are thoroughly tested before shipment. Dayton Audio products are warranted for the period of one
year. This warranty is limited to manufacturer defects, either in materials or workmanship. Dayton Audio is not responsible for any consequential on inconsequential
damage to any other unit or component or the cost for installation or extraction of any component of the audio system. In the rare case of a product failure, please
contact your place of purchase or call our Customer Support Department at [phone].

There are no other warranties, either express or implied, which extend the foregoing, and there are no warranties of merchantability or fi tness for any particular
purpose. The warranty will not cover incidental or consequential damage due to defective or improper use of products. This includes but is not limited to burnt
voice coils, overheating, bent frames, holes in the cone, or broken lead wires.

This warranty gives you specifi c legal rights and you may also have other rights which vary from state to state.
Non-Warranty Service: If non-warranty service is required, the product may be sent to the Company for repair/replacement, transportation prepaid, by calling [phone]

for details, complete instructions, and service fee charges.

Warranty Information

Warranty Limitations

daytonaudio.com

tel + 937.743.8248
[e-mail]

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705 Pleasant Valley Dr.
Springboro, OH 45066
USA

© Dayton Audio®Last Revised: 1/7/2015