All about jitter: causes, effects and solutions
What is jitter?
Jitter is a timing deviation in the transmission of audio signals. This irregularity can lead to poor audio quality and unsynchronized audio-video playback. Causes of jitter can be network delays, electrical interference or hardware problems.
Interface jitter
Interface jitter describes timing deviations when transmitting an audio signal from one device to another. This can be caused by different response times between devices and affects both analog and digital audio signals. High interface jitter can cause sound distortion. There are different types:
- Synchronization jitter: Caused by a lack of synchronization between devices.
- Transmission jitter: Caused by unsuitable transmission lines.
- Reception jitter: Occurs when a receiver does not process the signal correctly.
High-quality, synchronized sources and special jitter reduction technologies can be used to reduce interface jitter.
Sampling jitter Sampling jitter occurs when the sampling times vary when converting an analogue audio signal into a digital one. These variations can lead to sound distortions, such as noise or distortion, especially at high frequencies. Sampling jitter can be reduced by high-quality Analog-to-digital converter and minimize synchronization procedures.
How does jitter manifest itself?
Jitter can cause various symptoms:
- Irregular clicking noises in the audio signal
- Sound distortion, especially at high frequencies
- Unsynchronized audio-video playback
- Loss of clarity and dynamics in the sound
Does jitter affect the sound of audio?
Yes, jitter can significantly affect the sound. It causes distortions that appear as noise, blurring or loss of dynamics A higher jitter value usually leads to greater sound distortion.
How is jitter measured?
Jitter is often measured using special measuring devices called jitter analyzers. These devices record the time difference between incoming audio signals and display it graphically. There are also software solutions that can analyze jitter. Industry standards such as AES11 provide guidelines for the measurement.
What are good jitter values?
Acceptable jitter values vary depending on the application. Professional music recordings require very low values, often less than 1 nanosecond (ns). In everyday use, values as low as 50 ns can be acceptable without significantly affecting sound quality.
How to avoid jitter?
To minimize jitter, you can:
- Use high-quality, synchronized sources
- Use high-quality, galvanically isolated transmission media
- Use high-quality audio interfaces
- Use jitter reduction technologies
- Maintain and clean devices regularly
What is the jitter in the speed test?
In the speed test, jitter measures the variability of the latency times (delay times) during data transmission. A lower jitter value means a more stable connection.
What is high jitter?
A high jitter value is greater than 30 ms and can cause interruptions and poor performance in real-time applications.
What is jitter in VoIP?
In VoIP (Voice over IP), jitter means that voice data packets arrive unevenly. This can lead to poor voice quality, distortion or dropouts in calls. Low jitter values are particularly important here for clear communication.
