Cause of Subwoofer Burn Out: Amplifier Distortion

Cause of Subwoofer Burn Out: Amplifier Distortion


This year, we received feedback from a customer who purchased 2.0 DJ speaker systems from another supplier. They experienced a recurring issue where the subwoofer would burn out during extended playback sessions, and they reached out to us for technical assistance.

Cause of Subwoofer Burn Out: Amplifier Distortion
DJ/Karaoke Speaker System with Lights show

The Problem About The Subwoofer Burn Out From Customers
This year, we received feedback from a customer who purchased 2.0 DJ speaker systems from another supplier. They experienced a recurring issue where the subwoofer would burn out during extended playback sessions, and they reached out to us for technical assistance. 
Manufacturer AUSMAN AUDIO, with over a decade of experience in developing, manufacturing, and delivering 2.0 DJ speakers, is committed to helping customers resolve product issues.

The Main Causes of Subwoofer Burn Out Is Amplifier Distortion
In fact, there are several reasons why a subwoofer might burn out, but one of the primary culprits is amplifier distortion. When an amplifier receives a signal that is too large, it can enter a state of distortion known as clipping or overload distortion. Once distortion occurs in the amplifier, the distorted output signal can quickly lead to an increase in the temperature of the subwoofer's voice coil. If the input signal to the amplifier is not promptly reduced, it can result in the voice coil of the subwoofer burning out due to excessive heat.

The larger the power delivered to the subwoofer when amplifier distortion occurs, the faster the temperature of the voice coil rises, and the higher it gets. Since the power of the high-frequency driver in the speaker is much lower than that of the subwoofer, during amplifier distortion, the voice coil of the high-frequency driver warms up more slowly and to a lower temperature, making it less prone to burning out compared to the subwoofer.

Built-in Amplifier Speaker Rarely Cause Subwoofer Burn Out
Currently, most speakers are equipped with built-in amplifiers, known as active speakers. Speaker manufacturers design these products to create a balanced and sustainable system. During the design phase, factors like power ratings, voltage, current, and components such as internal batteries are carefully adjusted to ensure the system can perform reliably. Therefore, in everyday use, instances of subwoofer burn out in active speakers are quite rare.

China Manufacturer AUSMAN AUDIO specializes in active speaker systems, which are not only portable and convenient but also versatile for various settings, including indoor/outdoor events, classrooms, commercial functions, meetings, and gatherings.

Additionally, after the manufacturing process is completed, speaker factories conduct continuous playback aging tests on the speaker systems. This aging test involves powering the speakers, cranking the volume up to the maximum, and playing audio continuously for 48 to 72 hours. If any issues, such as abnormal sound, no sound, or circuit damage, arise during this test, they are identified and addressed before the products reach customers.

Analyzing the Cause of the Customer's Product Issue Above
Through our analysis of the customer's product, we determined that one of the primary causes of the subwoofer burn out was amplifier distortion. An indirect contributing factor to this incident was that the supplier failed to conduct thorough 48/72-hour aging tests after completing the production. Because the entire batch of speakers had already been shipped to the customer's country, we recommended that they negotiate with the supplier and consider replacing the components at a local speaker assembly facility. This approach would help minimize costs and losses.

the ampifier for tha passive speaker
How Can You Prevent Amplifier Distortion?
Understanding the operating status of the amplifier is crucial. Here, we'll use an external amplifier as an example because built-in amplifiers are pre-set, and regular users don't typically adjust their settings. Please check the picture above.

The signal indicator lights on the amplifier panel not only display the input signal's magnitude but also indicate the amplifier's current operating status. A green light signifies that the signal and amplifier are operating normally, a yellow light indicates a relatively high input signal, with the output approaching 50% to 80%, signaling a need to control the signal. A flashing red light indicates a very high input signal, with the amplifier output already at 100%. In this case, you should not increase the signal any further.

If the red light remains constantly lit, it means the amplifier has entered a state of overload distortion, which can burn out the subwoofer's voice coil within seconds. To prevent amplifier distortion, always monitor the input signal indicator light and, if you notice the red light coming on, immediately reduce the volume control on your mixer to prevent excessive signal levels.

Balancing the Speaker System To Prevent Burn Out Problem
Each speaker system's amplifier, drivers, working voltage, and other components are part of a balanced "design." This design is the result of extensive testing and engineering by the technical department. It ensures that the system can operate continuously and stably while meeting market demands. AUSMAN AUDIO works closely with each customer to develop unique designs, ensuring both brand distinctiveness and competitiveness in local markets.

What Can Speaker Manufacturer AUSMAN AUDIO Help You?
If you're experiencing issues with your speaker system, such as burned-out driver units, overheating during operation, or distorted sound playback, please don't hesitate to contact AUSMAN AUDIO. We're here to provide technical assistance and solutions for your audio needs.

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