Montarbo NM250A Active Loudspeaker User Manual

1. Introduction

Thank you for choosing the Montarbo NM250A Active Loudspeaker. This powerful bi-amplified active loudspeaker delivers 250 watts of total power, combining high sound pressure with a compact size and simple operation. It is designed for versatility, suitable for small shows, presentations, conferences, home recording, MIDI playback, and personal monitoring in rehearsal rooms. The NM250A performs exceptionally well in various environments, including medium-sized spaces, restaurants, clubs, and small auditoriums, providing excellent audio results with maximum ease of use.

This manual provides essential information for the safe and efficient operation of your Montarbo NM250A loudspeaker. Please read it thoroughly before use and retain it for future reference.

2. Safety Instructions

To ensure safe operation and prevent damage, please observe the following safety precautions:

• Power Supply: Connect the unit only to the specified voltage and frequency. Ensure the power cable is undamaged and properly grounded.
• Ventilation: Do not block ventilation openings. Ensure adequate airflow around the unit to prevent overheating.
• Moisture: Do not expose the unit to rain, moisture, or excessive humidity. Avoid placing liquids on or near the speaker.
• Placement: Place the speaker on a stable, level surface. When using pole mounts or stacking, ensure all connections are secure.
• Hearing Protection: Prolonged exposure to high sound pressure levels can cause permanent hearing damage. Use appropriate hearing protection when operating the speaker at high volumes.
• Servicing: Do not attempt to service this unit yourself. Refer all servicing to qualified personnel.

3. Package Contents

Please check that your package contains the following items:

• Montarbo NM250A Active Loudspeaker
• Power Cable
• User Manual (this document)

4. Product Overview

The Montarbo NM250A is a professional-grade active loudspeaker designed for clarity and power. Its robust construction and advanced features make it suitable for a wide range of audio applications.

Figure 1: Front view of the Montarbo NM250A Active Loudspeaker. This image shows the speaker's compact and robust design, featuring a protective grille over the woofer and a horn for the mid/high driver.

Key Features:

• Professional 2-way bass reflex design.
• Custom components built to Montarbo specifications.
• 8-inch woofer with a 2-inch voice coil, offering high efficiency and excursion.
• Mid/high driver with a 1-inch voice coil and constant directivity (H90° x V60°).
• Integrated bi-amplification with 2 Mosfet power units in Class AB.
• Maximum power output of 250 watts (200W for bass, 50W for mid/high).
• Active electronic crossover at 1600 Hz with 24 dB/octave slope.
• Neutrik-Combo input for versatile XLR and 1/4-inch jack connections.
• Balanced XLR output for linking multiple speakers.
• Multi-angle cabinet construction allows use as a stage monitor.
• Lightweight and robust polypropylene cabinet with a durable steel grille.
• Equipped with 2 x M8 threaded inserts, self-locking feet, a pole mount socket, and a side carry handle for easy transport and installation.

5. Setup

5.1 Positioning the Loudspeaker

The Montarbo NM250A can be positioned in several ways:

• Stand-alone: Place the speaker on a stable, flat surface.
• Pole Mount: Use the integrated pole mount socket to place the speaker on a standard speaker stand.
• Stage Monitor: The multi-angle cabinet design allows the speaker to be placed on its side for use as a floor monitor.
• Stacking: Multiple NM250A units can be securely stacked using their integrated feet and recesses.

Figure 2: Illustration of stacking two Montarbo NM250A loudspeakers. The image highlights how the speakers interlock for stable vertical placement.

Figure 3: Montarbo NM250A loudspeakers configured for stage monitor use. This image demonstrates the multi-angle design allowing the speaker to be angled on the floor.

5.2 Connecting Power

1. Ensure the speaker's power switch is in the OFF position.
2. Connect the supplied power cable to the AC inlet on the rear panel of the speaker.
3. Plug the other end of the power cable into a suitable grounded electrical outlet.

5.3 Audio Connections

The rear panel of the NM250A features various input and output options:

Figure 4: Front view and detailed rear control panel of the Montarbo NM250A. The rear panel shows the input/output connectors, volume, and tone controls.

• MIC/LINE Input (Neutrik-Combo): This input accepts both XLR and 1/4-inch (6.35mm) jack connectors. Use an XLR cable for microphone signals or a 1/4-inch jack for line-level signals from mixers, instruments, or other audio devices.
• LINK Output (XLR): This balanced XLR output allows you to send the audio signal to another active speaker or audio device. This is useful for daisy-chaining multiple NM250A units.

1. Connect your audio source (e.g., mixer, microphone, instrument) to the MIC/LINE Input using an appropriate cable.
2. If linking multiple speakers, connect an XLR cable from the LINK Output of the first speaker to the input of the next speaker.

6. Operating Instructions

6.1 Powering On/Off

1. Before powering on, ensure all volume controls are set to their minimum position.
2. Flip the POWER switch on the rear panel to the ON position. The power indicator LED will illuminate.
3. To power off, set the POWER switch to the OFF position.

6.2 Adjusting Volume and Tone

The rear panel features controls for adjusting the sound:

• VOLUME: This knob controls the overall output level of the speaker. Start with a low setting and gradually increase to the desired level.
• HIGH: Adjusts the high-frequency (treble) content of the sound. Turn clockwise to boost treble, counter-clockwise to cut.
• LOW: Adjusts the low-frequency (bass) content of the sound. Turn clockwise to boost bass, counter-clockwise to cut.

Adjust these controls to achieve the desired sound balance for your environment and audio source.

7. Maintenance

7.1 Cleaning

• Always disconnect the power cable before cleaning.
• Use a soft, dry cloth to wipe the exterior of the speaker.
• For stubborn dirt, a slightly damp cloth with mild soap can be used, followed by a dry cloth.
• Do not use abrasive cleaners, solvents, or waxes, as these can damage the cabinet finish.

7.2 Storage

When not in use for extended periods, store the speaker in a dry, dust-free environment. It is recommended to use the original packaging or a protective cover to prevent dust accumulation and physical damage.

Figure 5: Close-up of the side handle and M8 threaded insert on the Montarbo NM250A. This image illustrates the robust construction and practical features for handling and mounting.

8. Troubleshooting

If you encounter issues with your Montarbo NM250A, refer to the following common problems and solutions:

• No Power:
  • Check if the power cable is securely connected to both the speaker and the electrical outlet.
  • Verify that the power outlet is functional.
  • Ensure the power switch on the speaker is in the 'ON' position.
• No Sound:
  • Check the volume knob on the speaker and ensure it is not set to minimum.
  • Verify that the audio source is active and sending a signal.
  • Check all audio cables for secure connections and damage.
  • Ensure the correct input is being used and the input sensitivity is appropriate for your source.
• Distorted Sound:
  • Reduce the volume level on both the speaker and the audio source.
  • Check if the audio cables are damaged or improperly connected.
  • Adjust the HIGH and LOW tone controls to see if they are causing the distortion.
• Hum or Noise:
  • Ensure all equipment is properly grounded.
  • Try using different audio cables.
  • Move the speaker or audio cables away from power cables or other electronic devices that might cause interference.

If the problem persists after trying these solutions, please contact Montarbo customer support.

9. Specifications

10. Warranty and Support

The Montarbo NM250A Active Loudspeaker comes with a limited warranty. Please refer to the warranty card included with your product for specific terms and conditions. For technical support, service, or warranty claims, please contact your authorized Montarbo dealer or visit the official Montarbo website for contact information.