Tag Archives: Public Address Systems

Public Address Systems Set-up & Services

We offer installation, setup and repair services for public address systems, sound systems, home theatres and electronics. We also install and assemble sound systems for customers in and around Nairobi Kenya.

What Can Go Wrong With a Public Address Speaker?

Public address speakers often fail as a result of improper use. Some of the most common issues with these speakers include: public address systems services in Nairobi Kenya

1. A damaged enclosure that exposes internal components to damage
2. A blown electrical fuse
3. A blown thermal fuse
4. Faulty voice coil
5. Faulty crossover network
6. Damaged solder connections
7. Faulty cables
8. Improper cable connections
9. Damaged driver cone
10. The speaker might not be in phase
11. Broken level controls

How to Identify PA Speaker Problems

Tip 1– In case the loudspeaker is not producing any sound, check that the source component is properly connected and adjusted. If the components are well-connected, you’ll need to disassemble the cover.

First, power it off from the main power before any disassembling. Check the fuse for any signs of damage. If the fuse is blown, replace it.

Tip 2– If there is no sound from the drivers, try testing the fuse, drivers, and crossover wiring. Replace any damaged part. If possible, test the components on a similar speaker. If you still fail to get sound, the receiver may be faulty.

Tip 3– If one driver is not producing any sound, you’ll need to test it. You can press the cone lightly with your finger to check for any vibration. In case it’s not vibrating, then you should replace the driver.

Tip 4– If you’re getting distorted sound, try flexing the sound cable at low volume. If the sound changes while flexing the cable, clean the connectors and replace the cable. Also, check whether you’ve connected the cable properly. If no sound, press the cone with your fingers repeatedly. In case it’s not moving smoothly, replace the cone.

Tip 5– If the loudspeaker sounds noisy, the voice coil may be damaged. You’ll need to check it for any signs of damage such as holes. In case you find a hole, seal it with rubber cement. If the damage is major, replace the driver. If the cone has no signs of damage, try cleaning the volume control using an appropriate electronic contact cleaning agent.

Tip 6– In case you’re getting intermittent sound, check whether all connections are fixed properly. Also, check the coil and test the fuse.

Tools Needed For Fixing PA Speaker Problems

You’ll need these materials and tools to repair your loudspeaker:

• Replacement component
• Speaker repair kit
• Foam
• Wire
• Rubber cement
• Multimeter

How to Repair a PA Speaker

Step 1-Turn off the main power and unplug the power cable. If it’s not powered by AC, unplug any speaker cable.

Step 2– Next, start disassembling the speaker. Remove the grill to expose the drivers and crossover. Depending on the make of your loudspeaker, the grill may be secured with screws, snaps or glue.

Step 3– Detach the drivers. Some drivers are screwed while others are sealed. In case it’s sealed, use a sharp knife or blade to detach it. When reattaching the driver after repair, use an appropriate sealant in case it was sealed in place.

Step 4– Lift the speaker driver to expose wire connectors. Remove the connectors carefully with a pliers. Some connector wires may be soldered in place.

Step 5– Remove the crossover if necessary. Most crossovers can be accessed easily from the front while others can only be accessed after removing the main driver.

Step 6– Test the fuse using a multimeter.

Step 7– Using the multimeter, test the resistance on the crossover network, terminal block and the driver. The resistance of most drivers is written on the back in ohms.

Step 7– Replace any damaged component and reassemble the unit.

Repairing a Damaged Cone

If you found a small hole or tear on the cone, you’ll need to seal it. Apply some rubber cement on either side of the hole. In case the tear is extremely large, the cone may need replacement.

How to Obtain the Correct Polarities (Speaker Phasing)
If you have incorrectly attached the speaker cable, you’ll get poor sound or no sound at all. Thus, you need to ensure that the speaker is in phase. This means that the terminals should be properly connected. The positive terminal is usually red in color whereas the negative terminal is black.

However, if your cable is not colored, ensure the positive terminal of the source is connected to the positive terminal on the loudspeaker. The negative connector should go to the negative terminal. This way, you’ll get rich sound.

While identifying and fixing PA speaker problems, you might wonder whether to repair or replace some components. It’s often inexpensive to replace the fuse, cables and sealing tiny holes on the cone.

However, replacing the driver might be a bit more expensive depending on the brand. If it’s beyond your budget, you can have the driver re-coned. If an issue is beyond repair or replacement, consider buying a new PA speaker.

MORE ABOUT PUBLIC ADDRESS SYSTEMS

A public address (PA) system is a communication system used to broadcast audio messages to a large group of people in public spaces, buildings, or outdoor areas. It serves as a means of transmitting important information, announcements, music, emergency alerts, and other messages to a wide audience efficiently and effectively.

Components of a typical public address system:

1. Microphone: The primary input device used by the speaker to deliver their message. There are various types of microphones, such as handheld, headset, or lavalier microphones.
2. Mixer: The mixer is a control unit that allows the operator to adjust the volume and balance of different audio sources before sending the combined signal to the amplifier.
3. Amplifier: This device takes the low-power audio signal from the mixer and boosts it to a level suitable for driving the speakers. The power of the amplifier depends on the size of the area to be covered and the number of speakers connected to it.
4. Speakers: The speakers are responsible for converting the amplified audio signal into sound waves that can be heard by the audience. They are strategically placed throughout the area to ensure uniform sound distribution.
5. Audio Source: This can be any audio playback device like a CD player, MP3 player, or digital audio player that provides pre-recorded messages or background music.
6. Wiring/Cabling: These are the cables that connect the various components of the system, carrying the audio signal from the source to the mixer, amplifier, and finally to the speakers.

Purpose of public address systems:

1. Information Dissemination: PA systems are commonly used in places like schools, airports, train stations, and shopping malls to make important announcements and provide general information to the public.
2. Emergency Announcements: In emergencies such as fire, natural disasters, or security threats, PA systems play a crucial role in broadcasting evacuation instructions and other safety information to ensure people’s well-being.
3. Entertainment and Background Music: Public address systems are used to play background music and enhance the ambiance in public places, waiting areas, and commercial establishments.
4. Crowd Management: At events, concerts, or rallies, PA systems help event organizers communicate with the attendees, guide them, and maintain crowd control.
5. Advertising and Promotion: In some cases, PA systems are used for promotional purposes, such as advertising products, services, or upcoming events.

Public address systems are essential tools for effective communication and information sharing in public spaces, making them safer, more organized, and engaging for the audience.

Common Public Address System Problems

Public address systems can encounter various problems due to wear and tear, technical issues, or improper maintenance. Some common problems include:

1. Feedback: Feedback occurs when the sound from the speakers loops back into the microphone, creating a high-pitched, screeching noise. It can happen if the microphone is too close to the speakers or if the system’s gain settings are not properly adjusted.
2. Distorted Sound: Distorted or fuzzy sound can result from issues like damaged speakers, amplifier overload, or incorrect audio source settings.
3. Dead or Weak Batteries: In portable PA systems or wireless microphones, dead or weak batteries can lead to intermittent or no audio transmission.
4. Wiring Issues: Problems with cables and connectors can cause audio dropouts, static, or one-sided audio.
5. Faulty Microphones: Malfunctioning or damaged microphones can result in low or no audio output.
6. Inadequate Coverage: If the number or positioning of speakers is inadequate, some areas may experience poor sound coverage or be too loud in other areas.
7. Grounding Noise: Ground loops can introduce unwanted hum or buzzing sounds into the audio, especially if the system’s components have different grounding points.
8. Power Problems: Power failures or issues with the power supply can cause the PA system to stop functioning.
9. Interference: External sources like radio frequency interference or electromagnetic interference can disrupt the audio signal.
10. Incorrect Settings: Incorrect settings on the mixer or audio source can lead to imbalanced audio levels, making it hard for the audience to hear or causing sudden loud volume changes.
11. Aging Equipment: Over time, components of the PA system may degrade, resulting in reduced performance or increased susceptibility to technical issues.
12. Environmental Factors: Outdoor PA systems can face challenges from weather conditions like rain, wind, or extreme temperatures, affecting the equipment’s durability and functionality.
13. Software or Firmware Issues: If the PA system includes digital signal processing or advanced features, software or firmware bugs could lead to unexpected behavior.
14. Lack of Maintenance: Neglecting regular maintenance, cleaning, and inspection can lead to the accumulation of dust and debris, potentially causing performance problems.

To prevent or minimize these issues, regular maintenance, proper setup, and professional installation are crucial. Routine inspections and testing can help identify and address problems early, ensuring a reliable and effective public address system.

Repair solutions to common public address system problems

Repairing common public address system problems may require some troubleshooting and technical expertise. Here are potential solutions for some of the common issues:

1. Feedback:
   • Adjust the microphone position: Move the microphone away from the speakers to reduce the chance of feedback.
   • Use a directional microphone: Directional microphones are less prone to picking up sound from the speakers.
   • Lower the system’s gain: Reducing the gain on the mixer or amplifier can help prevent feedback.
2. Distorted Sound:
   • Check speaker condition: Inspect the speakers for physical damage or signs of wear. Replace damaged speakers if necessary.
   • Reduce the amplifier’s volume: Lower the volume on the amplifier to prevent distortion caused by overloading.
3. Dead or Weak Batteries:
   • Replace batteries: Install fresh batteries in portable PA system components or wireless microphones.
   • Use rechargeable batteries: Consider using rechargeable batteries to reduce long-term costs.
4. Wiring Issues:
   • Check cables and connectors: Inspect cables for damage or loose connections. Replace faulty cables or connectors.
   • Secure connections: Ensure all connections are properly seated and tightened.
5. Faulty Microphones:
   • Test with a different microphone: Verify if the issue lies with the microphone itself by using a known working microphone.
   • Repair or replace the microphone: If the microphone is damaged, seek professional repair or replacement.
6. Inadequate Coverage:
   • Re-position speakers: Adjust the placement of speakers to improve sound distribution throughout the area.
   • Add more speakers: If needed, consider adding extra speakers to cover dead zones.
7. Grounding Noise:
   • Use ground lift adapters: Ground lift adapters can help eliminate ground loop hum by breaking the ground connection.
   • Proper grounding: Ensure all components are grounded properly to minimize interference.
8. Power Problems:
   • Check power supply: Confirm that the power supply is functioning correctly and providing the correct voltage.
   • Use surge protectors: Protect the system from power surges by using surge protectors or uninterruptible power supplies (UPS).
9. Interference:
   • Identify and remove sources of interference: Identify and eliminate nearby devices causing the interference.
   • Shielding: Use shielded cables and equipment to reduce susceptibility to external interference.
10. Incorrect Settings:
    • Re-adjust settings: Check the mixer and audio source settings to ensure proper levels and configurations.

For more complex issues or if you are unsure about performing repairs, it’s best to seek the help of a professional audio technician or a qualified PA system service provider. Regular maintenance and inspections can also help identify potential problems early and prevent major issues in the future.