|
Changing the dynamic range of an audio signal is inherently a non-linear process.
Unlike an ordinary line amp, the gain of a dynamic range processor is not constant – it varies with time depending on the specific control algorithm of the dynamics processor and the changing amplitude of the input signal. These variations in the gain, which represent the real control process, should take place without any bothersome side effects to the audio signal itself, effects such as pumping, signal distortion, sound coloration, or noise modulation. In other words, they should be inaudible.
The setting of the attack time parameter of a dynamics element effects how the unit will react to rapid amplitude changes in the audio signal. A long attack time leads to overshoots (and consequent distortion) because the system is not fast enough to reduce the gain. A short attack time minimizes the chance of overshoots, but the more rapid gain changes in such cases have audible side effects such as " clicks" and other modulation artifacts.
Traditional Compressor and Limiter Designs
Traditional compressor and limiter designs only have one control circuit with one attack time and one release time. They must be adjusted manually by the user to optimal settings for processing with as little disturbance as possible through a process of trial and error. A lot of experience and a lot of time is necessary to get acceptable results. These settings, once found, are only the right choice for a certain program signal and must be changed for other program types.
 Multi-band designs
These units split the audio frequency spectrum into several frequency bands. The attack and release times are set independently for each frequency band, giving independent processing for each band. The problem with this multi-band approach comes when the outputs of each band’s processor are combined together to produce the output audio. The spectral balance of this output signal is always different from the input. The balance of high, mid, and low frequencies is inherently disrupted, which is particularly objectionable when the signals are music, as in commercials, concerts, etc.
Multi-Loop designs
The Jünger Audio Dynamics Processors work according to a Multi-loop principle. The various loops each work over the entire frequency spectrum. They work in parallel, each with a different set of attack and release parameters. Each loop develops a control signal which is then summed with the controls from the other loops to produce a single gain control signal applied to one gain control element. Please see the figure below.
Look Ahead
The digital implementation of the Jünger Multi-loop design also permits a very short time delay to be introduced in the audio signal path. This lets the gain changing elements “look ahead” and determine the correction needed and to apply it to the delayed signal just in time to control even the fastest transients. This is particularly important for the limiter, which provides a precisely leveled output signal absolutely free of overshoots (clipping).
Adaptive Dynamic Range Control
The proprietary algorithms in the Jünger System also allow the automatic adjustment of the attack and release times according to the evolution of the input signal over time. This is called Adaptive Dynamic Range Control. By monitoring the waveform of the incoming audio, the System can set relatively long attack times during steady-state signal conditions but very short attack times when there are impulsive transients.
The Best Performance
The dynamic range processor principles developed by Jünger Audio make it possible to realize dynamics processors (compressor, limiter, expander) with very high audio quality, without signal coloration, pumping or breathing, and without distortion and modulation products.
In short, they offer the best possible performance -- inaudible dynamics control.
For more information, please Contact
Us. |
