Despite the digital revolution in the pro audio industry, many of today’s top albums are still mixed with analog outboard gear. Mixing with analog devices often still sounds better to many people. There is a very elusive and almost "magical" quality imparted from analog signal chains that is missing in the digital realm. There appears to be more weight to a mix, and the overall sound is more three dimensional. Analog devices produce electrical artifacts that affect frequency response, add harmonics, cause signal clipping and increase noise. These artifacts, which audio engineers often consider the character of a particular device, result from a combination of factors such as component grade, technology type (i.e. vacuum tubes, ICs, transistors), power supply specifications, equipment casing and other variables.
Depending on the circuit characteristics, input signal frequency response varies. Some circuits cut frequencies, others boost them. This behavior is part of the overall device character and should not be confused with user adjustable EQ.
Total harmonic distortion (THD) is based on the levels of the odd and even harmonics of an input signal, usually at a level much lower than the fundamental level. THD balance and decay are circuit dependent, and thus differ from device to device.
CrossTalk and Noise are two elements which every designer tends to avoid to not affect the audio quality. Since in the analog world they can't be avoided, fortunately in digital domain with Volterra Technology we have reduced the noise at less of -120dBfs and completely avoided CrossTalk during the sampling.
The result is an optimum full quality sound from a like-new working condition hardware.

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