About Dynamic Volume
The listening experience is greatly diminished when there are significant shifts in volume between television programs, commercials, and within program material. The user must constantly adjust the volume to maintain the desired listening level so dialog is clear and sound effects and commercials are not overwhelming.
Audyssey Dynamic Volume monitors the volume of program material moment-by-moment, maintaining the desired listening level for all content while optimizing the dynamic range to preserve the impact. With this innovative technology, the user no longer has to constantly reach for their remote control volume button.
Background
There are two main causes of differing volume levels within broadcast, commercials, and DVD content:
- Lack of volume standards among broadcast, content and equipment companies.
- Poor translation of content produced on systems with wide dynamic range and reproduced on systems with limited dynamic range such as TVs, HTiBs, and home theater systems not playing at full reference volume.
Attempts at solving this problem have been largely ineffective for several reasons:
- Most are designed to only look at the signal levels and not the perceived loudness
- Those that look at loudness do not make use of the correct psychoacoustic models
- They have no knowledge of the actual sound pressure level in the room
- They typically look at only a small number of frequency bands
- They perform simplistic dynamic range compression methods with fixed time constants
As a result, these attempts at leveling volume produce plainly audible artifacts, such as sudden increases and drops in level, that detract even further from the listening experience.
History of Dynamic Volume
Under the direction of Audyssey Chief Scientist Tomlinson Holman, it took years of research and experimentation for Audyssey researchers and engineers to make Dynamic Volume a reality. The first step was to carefully study how people interact with their volume controls over the course of their listening experience. This demanded extensive experimentation and hundreds of hours of data-gathering from a range of listeners, from typical consumers to professional mixing engineers.
Audyssey researchers instructed their participants to watch and listen to entire movies in differently-treated acoustical environments, from simple listening rooms to acoustically-treated theaters. Subjects were directed to adjust the volume control as if they were listening in their homes, yielding valuable data on how people compensate for changes in listening volumes such as:
- Raising the volume to hear dialogue nuances, and then readjusting when sound effects become too loud.
- Immediately reducing volume when loud, overbearing commercials start after a program break.
Multiple terabytes of data were collected and processed in the course of this research, a feat that, not long ago, would have been insurmountable. Audyssey researchers and engineers analyzed this vast amount of data and crafted an accurate representation of how a typical listener controls their volume range for home listening.
This data and the correlation to the measured content loudness, led to the development of Dynamic Volume. Audyssey engineers successfully implemented this technology so volume remains consistent across multiple sources, such as live and recorded television programs, commercials, and music. The creation of Dynamic Volume proved to be one of the most technically complicated problems Audyssey has tackled to date.
Audyssey technologies work together to solve the complex problems that arise when attempting to reproduce sound as it was originally conceived. Audyssey Dynamic Volume includes Audyssey Dynamic EQ, which compensates for deteriorating sound quality as volume is decreased by taking into account human perception and room acoustics.
As part of Dynamic Volume, Dynamic EQ selects the best possible frequency response and surround volume levels on a moment-by-moment basis. These two technologies enable the full frequency response of the source at its original level to be reproduced at any listening level. Even at lower listening volumes, Dynamic Volume ensures that the richness and dynamics of the response are maintained.
Dynamic Volume employs advanced audio signal processing that operates in both the time and frequency domains. The spectral content in individual channels and the surround mix are continuously monitored in order to maintain proper spatial volume. Both rapid and slow changes in level and dynamics are monitored in order to prevent the common artifacts produced by standard compressor methods.
Conclusion
Audyssey Laboratories was founded on the principle of producing the best possible translation of music, movies and television programs for the home. Its flagship technology, Audyssey MultEQ, measures and removes the distortion caused by room acoustics. Audyssey Dynamic EQ solves the problem of deteriorating sound quality as volume is decreased by taking into account human perception and room acoustics. Audyssey Bass XT delivers deeper bass response from smaller subwoofers by actively monitoring the incoming signal and pushing subwoofer excursion to maximum levels at all volume settings. And now, Audyssey Dynamic Volume delivers consistent volume playback levels, anticipating sudden spikes and dips in volume and compensating for them in real time. This newest technology frees listeners from having to constantly reach for the remote control when watching TV or DVD movies.