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HD-MA35
INSTALLATION AND OPERATION
INTRODUCTION
Congratulations on your selection of an RDL HD-Series High-Efficiency commercial mixer amplifier. The HD-MA35 is part of the world’s highest performance full-featured high-efficiency mixer
amplifier series for commercial installations. This product includes a studio quality microphone input stage, line-level transformer isolation, equalization, remote control capability and integral
analog compression coupled to a sonically pleasing analog-filtered high efficiency Zone 1 Class D output stage. The HD-Series mixer amplifiers are designed and manufactured in the U.S.A.
using the most advanced automated manufacturing and testing processes for years of reliable high performance and cost savings.
CONNECTIONS
USE ONLY THE POWER SUPPLY
SUPPLIED WITH THE MODULE.
HD-MA35 4Ω/8Ω
Connections are made on the rear panel. All connections are on detachable terminal blocks or connectors. The Zone 2 mixer, Input 1 MIC/LINE switch, ducking controls and assignments and phantom
voltage selector are also provided on the rear panel. The Zone 1 mixer, tone controls, indicators and power button are on the front panel.
INPUT WIRING
Balanced MIC or LINE source connected
using a single-pair shielded audio cable
Balanced LINE signal from phone
PBX or audio transformer
Unbalanced MIC or LINE source connected using
a single-conductor shielded audio cable
Three inputs may be connected. Each input is available on the primary Zone 1 front-panel mixer and on the Zone 2 rear-panel mixer. If used, the paging source is usually connected to Input 1.
INPUT 1
INPUTS 2 & 3
PHANTOM VOLTAGE
If a condenser mic may be connected to INPUT 1, set the phantom voltage ON (switch up).
LEFT
MIC or LINE Gain
Set the Input Gain to MIC or LINE/TEL according to the input
signal connected.
INPUT 1
Connect a MIC or LINE source. This is normally a paging mic or the line-level paging output from a phone PBX. The line-level
input is transformer balanced (providing galvanic isolation) and may be connected balanced or unbalanced.
PRIORITY PAGING
INPUT DUCKING SELECTOR
Select one or both inputs (2 and/or 3) to be ducked when a paging priority is detected (VOX activated by audio signal on INPUT
1, or MANUAL activation by an external switch. Selected inputs are ducked only in Zone 1 (the primary amplified output). Set
the switch ON (switch up) to duck the input in Zone 1; set the switch OFF to prevent ducking. Inputs are not ducked in Zone 2.
VOX (VOICE-ACTIVATED PRIORITY)
If a paging signal is to automatically “duck” (fade down) other
audio inputs, feed a normal paging signal into INPUT 1 and adjust
the SENSITIVITY trimmer until the LED flashes regularly. Set the
SENSITIVITY trimmer fully CCW to disable the VOX function.
STEREO SOURCE
RIGHT
MONO SOURCE
INPUTS 2 & 3
Connect a mono or stereo standard unbalanced -10 dBV audio
source to INPUTs 2 and/or 3. The two input jacks associated with
each input provide active summing of the left and right channels,
thereby preserving the stereo separation of the audio source.
MANUAL PRIORITY
If a swich (such as a momentary paging mic push-to-talk switch) should “duck” (fade down) other audio inputs, connect the switch to the DUCK and Ground terminals.
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REMOTE CONTROL FOR ZONE 1 AMPLIFIER OUTPUT
MASTER VCA REMOTE CTRL
Connect the VCA terminals directly to an RDL remote control. (Examples providing a single volume control location: RLC10K or RLC10KS; RLC10KM or RLC10KMS with pushbutton muting) Other RDL remote
controls are available to provide multiple control locations. Visit rdlnet.com for details. The VCA may be controlled by an external 10 kOhm linear pot or from other equipment control outputs that provide 0 to 10Vdc.
External 10k Pot
(Linear Taper)
CW
CCW
External Control
0 to 10 V
Wiring may be unshielded or single-pair shielded (connect the shield between the ground terminals). Shielded wiring is recommended for installations in
environments where radio frequency emissions may be present.
EXTERNAL MODULES
MODULE MOUNTING AREA
This area is reserved for mounting RDL STICK-ON
or TX-Series modules. The example shows a mixer
module that provides additional inputs to the mixer
amplifier. Other possibilities include equalizers, signal
detectors, crossovers or processors.
MODULE POWER
24 Vdc, 100 mA is available to power external modules.
3 Mic/Line Inputs
ZONE 1 OUTPUT CONNECTIONS
DO NOT GROUND EITHER SPEAKER OUTPUT TERMINAL
IMPEDANCE SWITCH
IMPEDANCE SWITCH
Set to 8 Ohms
Single 8 Ohm speaker
ZONE 2
Two 8 Ohm speakers
Set to 4 Ohms
IMPEDANCE SWITCH
Set to 4 Ohms
Single 4 Ohm speaker
INPUTS
Adjust for desired
output level
Balanced LINE signal feeds phone PBX
0 to 10 V
Ground Reference
IMPEDANCE SWITCH
Set to 8 Ohms
Two 4 Ohm
speakers
Connect an 8 Ohm speaker or multiple
speakers configured to present an 8 Ohm
load to the amplifier.
The Zone 2 mixer operates from the same 3 inputs as the front-panel Zone 1 mixer. Ducking assignments do not affect the signals in
LINE OUTPUT
Transformer isolated
ADDING ZONES OPERATION
Zone 2. Each input source should be adjusted to the desired output level. Turn down unused inputs to remove them from the mix. Two
Zone 2 outputs are provided. The 600 Ohm output is transformer isolated (providing galvanic isolation) to drive a phone PBX paging
input or the input of another power amplifier. The 8 Ohm output drives an 8 ohm speaker with up to 2 W RMS.
TONE CONTROLS
Adjust BASS and TREBLE as desired.
POWER BUTTON
Latching pushbutton turns the amplifier
ON or off (STANDBY).
POWER INDICATOR
Glows dimly when unit is in standby (off)
mode; glows bright when amplifier is on.
ADDITIONAL ZONE AMPLIFIERS
Connect the LINE OUTPUT to the line input of one
or multiple additional RDL amplifiers to permit the
Zone 1 mixer to feed other zones. The LINE OUTPUT
is not controlled by the master VCA remote control so
each additional zone may have its own master level
control. The LINE OUTPUT provides “flat” audio without
equalization by the front-panel tone controls. The LINE
OUTPUT may also be used to feed recording equipment or
an audio distribution amplifier.
RDL• 659 6th Street • Prescott, AZ • USA 86301 • Sales: 800-281-2683 • 928-443-9391 • Tech Support: 800-933-1780 • 928-778-3554 • RDL Europe Sales & Support: (31) 20-6238-983 • www.rdlnet.com
891-3400A
Copyright © 2011 Radio Design Labs, Inc. RDL, Radio Design Labs and the RDL logo are registered trademarks of Radio Design Labs, Inc. Data reflects product at publication time, subject to change without notice. “Made in USA” applies to all HD products except power supplies. Other trademarks, if any, are the property of their respective owners.
SIGNAL PRESENT 1 - 3
MIXER LEVEL 1 - 3
Adjust each level control for the desired output level. If a master remote control is connected, it will adjust the final
mixer output level feeding the Zone 1 amplifier.
The green LED glows when audio is present at the input. The indication is not affected by the setting of the mixer level control.
COMPRESSION INDICATOR
LED flashes when audio compressor is
acting on the amplified audio.