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The newly developed volume control called AAVA (Accuphase Analog Vari-gain Amplifier) is totally different from conventional controls using resistors. It allows
precise listening level adjustment while maintaining top-notch performance and sound quality over the entire range. Because the music signal does not pass
through variable resistors, it is not affected by changes in impedance. This means that high signal-to-noise ratio and low distortion of the signal are maintained.
Internally, a dedicated CPU selects the current switches that determine the gain of the amplifier. With regard to the music signal, the AAVA circuit is a fully analog
volume control.

AAVA operation principle
AAVA operates by feeding the music signal to a V-I (voltage - current) converter
where it is weighted in 16 steps [1/2, 1/22, ... 1/215, 1/216]. The 16 current steps
are turned on or off by 16 current switches, and the combination of switch
settings determines the overall volume. The switching operation is controlled
by a CPU according to the position of the volume control knob. The combined
signal current forms a variable gain circuit that adjusts volume. Finally, the
combined current is converted back into a voltage by an I-V (current - voltage)
converter.

AAVA resolution
AAVA adjusts the listening volume by means of 16 current switches. The
number of possible volume steps set by the combination of these switches is
2 to the power of 16 = 65,536. When maximum output voltage is 5 V, resolution
is an amazing 0.07 mV.

Minimal distortion and no thermal noise
Because AAVA is an electronic circuit, the music signal does not pass through
any variable resistors. Thermal noise caused by resistors is totally absent.
Because there is no impedance that affects the signal, S/N ratio remains at
the logical optimum. The circuit configuration also assures ultra-low distortion.

Simple circuit configuration
AAVA unifies the amplifier and volume control functions, resulting in a circuit
that is electrically very simple. Right and left channels are fully independent,
and frequency response does not change regardless of the volume control
knob position. Channel separation is excellent, and sonic performance remains
totally uniform over the entire range.

AAVA means analog processing
The AAVA circuit converts the music signal from a voltage into a current, alters
gain by means of current switches, and then reconverts the current into a
voltage.

Same operation feel as a conventional high-quality volume control
The actual volume control knob is linked to a variable resistor. However, this
resistor is only used to detect the absolute position of the knob. Operating the
control therefore feels exactly the same as with a conventional control, and
operation via the remote commander is also possible.

Attenuator and balance control also realized via AAVA
The functions of the attenuator and the left/right balance control are covered
by the AAVA circuit as well, eliminating the need for additional stages. Keeping
the configuration simple helps to maintain high performance and sonic purity

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Men är "AAVA" någonting nytt egentligen?...det är väl en Multiplicerande DA-omvandlare bara?

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With regard to the music signal, the AAVA circuit is a fully analog
volume control.

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