Music Comes First
With Audirvana, convert your computer into a true
high-fidelity audio source that nothing will alter.
Audirvana takes control of the computer’s audio flow, minimizes the signal path, and ensures internal bit-perfect processing. It bypasses the internal audio mixer, avoiding sound events from other applications and unwanted changes to the audio format of your music.
Control of the Audio Flow
In normal use, computer audio playback consists of a sequence of independent tasks. After reception and decoding, the signal passes through an audio “mixer” that combines sounds from different applications. After reception and decoding, the signal passes through an audio “mixer” that combines sounds from different applications. This mixer modifies the resolution of audio samples under a “lowest common denominator” rule and uses a low-power algorithm to avoid extra latency, which adds quantification artifacts on top of quality loss. To avoid interference and damage, Audirvana reserves exclusive access to the audio device and minimizes the number of operations depending on the characteristics of the output converter. The format thus remains unchanged from end to end (bit-perfect). The implementation differs according to the OS: With Mac, it is necessary to impose an integer mode calculation (as opposed to floating) to neutralize the mixer. With Windows, the format remains consistent when the WASAPI driver has exclusive access.
Quiet on the Set, Please!
Audirvana’s SysOptimizer prevents jitter-induced glitches and possible signal interference by stabilizing the computer’s power supply and minimizing processor activity minus 0.5 percent CPU load. To do so, Audirvana operates with an extended buffer memory and performs digital processing and decoding of audio formats before playback.
Digital information is transmitted in your computer as a square-shaped analog electrical waveform, interpreted as “0” or “1” if below or above a voltage threshold. When this musical information is played in rhythm (synchronous SPDIF or I2S protocol), slight variations in the voltage around the limit induce slight time-shifts that alter the signal (known as digital jitter)
Two phenomena can cause these errors: voltage jumps from the computer’s power supply and electromagnetic interference. Indeed, your computer, like any electrical device—and the devices connected to it via USB—undergoes voltage jumps due to internal activity peaks. The printed circuits can act as antennas or transmitters if an alternating electrical current flows through them, and are even more sensitive downstream of the DAC when the signal has returned to analog. Thus they can be affected externally by radiation and internally by the processor’s high-frequency switching radiation.
Audirvana reduces these activity peaks by stabilizing and limiting processor activity, and by pausing other application activity and hidden tasks on the computer. It does this with an extended buffer memory which makes it possible to smooth and perform upstream most processes such as audio decoding. During playback, CPU activity is maintained at less than 0.5 percent of capacity. In addition, Audirvana takes priority over processor usage, and allows you to manage authorized or unauthorized tasks on your computer during playback (using SysOptimizer in MacOS and the Fidelizer tool under Windows).
Adapting Your System
Audirvana provides the internal or external digital-to-analog converter (such as a USB DAC, streamer. or wireless speakers) with a “ready-to-play” digital stream (properly decoded format) thus reducing its processing load. It is even possible to allow the DAC to avoid oversampling by running higher-performance algorithms (SoX) directly in the computer which offers much more computing power (in 64-bit systems).
Optimization of the DAC
The digital-to-analog converter, or DAC, transforms the signal from digital to analog before transmitting it to the speakers. It is a critical element of your system that plays a major role in overall audio quality. The computer has a DAC for its internal speakers or headphone output. The DAC is external if you use a hi-fi system or active speakers and signal processing is performed before reaching it. Today, all DACs switch at high frequencies, well beyond the sampling frequency of your music. They therefore carry out “oversampling” with calculation resources and algorithms that vary greatly depending on the quality of the DAC. Audirvana always transmits a “ready-to-play” audio stream, i.e. a PCM (or DSD) stream already decoded, that takes into account the characteristics of your DAC and reduces the tasks to be performed at speaker level. In addition, Audirvana offers you the ability to perform “oversampling” upstream, using the much more powerful resources of the computer with a high-quality algorithm (SoX).