Why Phone Call Audio Quality Remains Poor Despite Technological Advancements

The audio quality of phone calls has been a concern for many users despite significant technological advancements. While modern systems and codecs have improved the situation, several factors continue to affect the clarity and overall quality of voice transmissions. This article delves into the reasons why phone call audio quality still struggles and identifies potential solutions.

Compression Techniques and Codecs

To transmit voice over cellular networks efficiently, audio is often compressed. This compression technique reduces bandwidth usage but can lead to a loss of audio quality. Different codecs are used, and their primary focus varies. Some codecs prioritize clarity (quality) over compression efficiency, while others prioritize the latter. The choice of codec can significantly impact the perceived audio quality of a phone call.

Network Limitations and Infrastructure

The quality of a phone call heavily depends on the network infrastructure. Weak signal strength or high network congestion can degrade call quality. Although Voice over LTE (VoLTE) and 5G technologies aim to improve this, they are not universally available. These advanced systems can enhance call quality, but coverage is limited in many areas.

Background Noise and Acoustic Interference

Most phone calls occur in environments where background noise is present. While noise-canceling technology has made significant improvements, it is not always effective. In some cases, noise-canceling technology can even lead to muffled audio. The interference from background noise can make it difficult to understand and communicate clearly on a phone call.

Device Microphone and Speaker Quality

The quality of microphones and speakers in smartphones varies significantly. Lower-end devices might use components that cannot capture or reproduce sound as accurately. High-quality microphones and speakers are crucial for maintaining a clear and lag-free audio experience. Users anticipate the best possible audio quality, and lower-quality devices often fail to meet these expectations.

Latency and Jitter in Digital Communication

Latency and jitter in digital communication can disrupt the natural flow of the conversation, making it seem less clear. These technical issues can be attributed to delays introduced during the transmission of audio data. Ensuring consistent and low latency is essential for maintaining a smooth and high-quality audio experience.

Legacy Systems and Inheritance

Many calls still route through legacy systems designed for basic voice transmission. These systems often limit the potential for high-quality audio. The audio quality in these systems is constrained by their design and infrastructure, which can be significantly different from modern systems.

User Expectations and Traditional Experience

Many users are accustomed to the traditional phone call experience and may not notice the difference in quality unless they use high-fidelity audio services. The convenience and familiarity of the traditional phone call often overshadow any improvements in audio quality.

Compatibility and Bandwidth Constraints

The bandwidth of old analog telephone lines is limited to 300–3000 Hz, requiring approximately 8 kbps to sample audio data. When digital telephony was developed, the goal was to ensure compatibility with older analog systems. As a result, the format was kept similar to accommodate both digital and analog devices. This historical constraint can limit the quality of audio transmitted over some phone lines.

Conclusion

While advancements like HD Voice and improvements in network technology aim to enhance call quality, several factors continue to limit the overall experience. To improve phone call audio quality, a comprehensive approach is required, addressing compression techniques, network infrastructure, device hardware, and user expectations. Moving towards higher-quality devices, ensuring robust network coverage, and continuing to innovate will ultimately enhance the phone call experience for all users.