GENERAL FEATURES
Conformity with “E” norms
VRx models have a RF filter which makes them suitable to the new norms about radio-frequency disturbances
emission inside cars before any others. A “common mode”, adequately dimensioned filter choke was inserted
next to power supply input in order to prevent sudden voltage drops which commonly occur in similar circuit
typologies.
Thermal limiter onto transformers
A very effective protection circuit was put onto transformers to prevent them from exceeding temperatures
which might be dangerous for the amplifier integrity. This circuit intervenes by having VRx stop; the amplifier
will start to function again only after the necessary cooling and reset operation (on and off again) will have to
be carried out.
LNS (Line Noise Suppressor) circuit
LNS circuit allows the system low frequency disturbances rejection, reducing the ordinary noise due to car
electrical parts (alternator, electronic injection, etc.). It does not affect sound and is effective in most cases. The
special switch which is onto all models except VRx 6.420 (where it is not indicated since it is constantly active)
permits to check if its intervention is necessary in case there are several VRx configured in cascade.
TPC.2 (Twin Power Controller) power supply stage handling system
TPC.2 allows to increase power supply stage handling speed (10 times approx.). This implies higher available
impulsive power and lower stress of filter capacitors.
OCN (Off Current Null) and DVP (Damaging Voltage Protection) circuits
Thanks to OCN circuit, VRx models are the only ones to be in conformity with max absorption new standards
when amplifier is off. Their value (0.00005A) makes them be 10 times below the maximum allowed limit. DVP
circuit protects VRx amplifiers from voltage increases and electrostatic discharges.
Synchro-PWM power supply
Power supply stage consists of two totally separate and synchronised sections: one for positive and one for
negative voltages. It is therefore possible to satisfy the final stage current demands more promptly,
guaranteeing higher energy and speed with low frequencies.
Final stage driver modules: LD1.2 and DHF.1
Final stage driver modules (LD1.2 for VRx2-4-6; DHF.1 for VRx1) sum up all audison’s experience of amplified
sound characterisation. Subjected to continuous studies and improvements, they further increase linearity and
acoustic impact with low frequencies in the current VRx version.
DFL (Distortion Frequency Limiter) circuit
DFL circuit is a real electronic protection for speakers. It limits max distortion factor to 6% onto low frequencies
and to 2% onto high ones. This implies constant and systematic control onto all audio range and wide safety
margin for all speakers in the system.
Sub input (VRx6.420)
VRx6.420 PRE OUT output can be used as IN Sub input in order to use this model with the head units which
have a third preamplified output for the subwoofer, exploiting the amplifier internal filter.
RGP input stages protection
(Resettable Ground Protection)
RGP is an electronic protection able to detect high direct current passage onto input ground; it acts by putting
the device in “stand by” condition (safety). The main feature of this circuit is its being able to work even when
the amplifier is off, allowing the interruption of current passage towards input stages in case of power supply
transformers short circuit. It perfectly guarantees the system safety since it consists of several sensors.
Three way, big size terminal block
VRx terminal block can accept cables up to 2 gauge section. A third positive pole houses the external capacitor
(+C) which, thus, directly acts onto power supply voltage seen by the amplifier. This minimises voltage drop
and cable overheating. Fastening screws are protected by a polycarbonate door. Inside the terminal block there
is also a location for a strip fuse which can be inspected through the device bottom, that protects electronic
circuitry and external capacitor. This solution allows the installation to be cleaner and the terminal block-fuse
holder system to have 300A approx. max capacity.
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Front/Rear configurations
Multichannel Configurations
A, B and C bridged amplifiers configurations
= Released switch.
= Pushed switch.
IN2 = Sub level: Sub is driven by IN1 + IN2. Fader is used to adjust sub level.
IN2 = Not used: Sub and Front driven by IN1.
Channels are driven by PC36 (PC36 always takes signal from IN1)
Sub is driven by IN1 + IN2 NO FADING SUB (with active Constant Bass)
Note:
Channels are driven by PC36 (PC36 always takes signal from IN1).
Sub is driven by IN1 + IN2.
Note:
MA, MB and MC on position 2 (mono)
VRx6.420
=Switch involved
in configurations.
