The section is currently under development ...

Four-channel Car Amplifier X1 mk2

Online Catalog

Our Four-channel car amplifiers of Hi-End class with TOSLINK optical & RCA analogue inputs have selectable “tube” and “transistor” play back modes and DSP modules to adjust sound levels to match your preferences and requirements.



Change the program in the DSP individually!



Class AB power amplifiers supplied with MOSFET output transistors can operate in the tube mode producing extraordinary sound effects, dynamic & realistic sound images.


Listen to the tube sound without distortions!


Static power supply units are spaced on separate boards & isolated from the amplifier boards with electromagnetic shields. This type of construction minimizes the electromagnetic interference and separate voltage regulation ensures the steady operation of the power amplifier.

X1-models discussion on the ""

Reviews about X1-model on the ""


Х1 mk2 Features

Audio inputs:

·        Toslink optical input/output (PCM / SPDIF-format / No Dolby Digital);

·        analogue RCA-type jacks.


Power amplifier specifications:

·        selectable "tube" and "transistor" play back modes;

·        MOSFET output stages with customized transistors made on our specifications operate in AB-class;

·        cascode type of power amplifier with phase-splitter, based on the differential circuit of MOSFET transistors;

·        discrete circuitry of each channel;

·        double-sided printed boards with 70 μm copper foil;

·        twisted pair cabling of power circuit;

·        the usage of chip-elements reduces the amount of electromagnetic interference and maintains the temperature balance of the circuit;

·        relay-actuated switch of the amplifier output, built in current sensor;

·        high-quality LowESR electrolytic and film capacitors;

·        short signal paths (for both analogue and digital sound).


DSP board:

·        Toslink optical input/output

·        all digital signals are processed into the 24 bit/96 kHz format with Cirrus Logic’s CS8422 Digital Audio Receiver.

·        56-bit DSP (ADAU1702 by Analog Device Inc.) for high quality sound processing;

·        24-bit ADC and DAC with sampling rate 96 kHz;

·        analogue signal is processed into the 24 bit/96 kHz format with integrated AD converter ADAU1702;

·        You can change the program in the DSP using the "Sigma Studio” visual programming by connecting your personal computer to the DSP block via the interface block, analogue to USBi (see here);

·        analogue signal, the amplifier receives, is formed either by the 24 bit/96 kHz built-in DA converter (integrated AD converter ADAU1702) or passes directly via RCA output through the only feed-through film capacitor and volume control;

·        stabilization of the clock frequency of the DAC and Digital Audio Receiver via high-precision shielded quartz crystal-controlled generator powered from a separate stabilizer;

·        the crossover of the 3-rd order with passive high-pass filter realized by operational amplifier OPA4134 powered by separate stabilizer;

DSP Board (ADAU1702)


Power Supply Board:

·        galvanic isolation of in-/output of the power supply unit, the feedback loop, TL431 reference-voltage source stabilizer;

·        separate voltage regulation;

·        protected from polarity reversal, short-time input voltage overlapping, the power supply unit overheating and short-circuit at the output;

·        minimal interference to a vehicle electrical system;

·        input/output filters with the cores made of amorphous metal;

·        LowESR electrolytic and film capacitors ensure high peak current and minimal interference; 

·        double-sided printed boards with 70 μm copper foil. 


Power Amplifier Construction:

·        massive housing enables the amplifier output stages heat removal;

·        the twisted-pair wires are used;

·        double-sided printed boards ensure the minimal level of distortions;

·        electronic system of short-time input voltage overlapping, the power supply unit overheating and short-circuit. 


Technical Specifications:

Number of channels 4
Class of power amplifier operation АВ
Total power output (RMS) 4 x 80 W
Selectable "tube" and "transistor" play back modes Yes
Types of speakers connections Standard / Bi-Amping
Toslink optical input (SPDIF/PCM format) Yes
RCA analogue output Yes
Built-in digital sound processor (DSP) Yes
Direct leakage (Direct) Yes
Built-in ADC, DAC modules (AD1702 от ADI) 24 bit, 96 kHz
Crossovers of 2-nd order for frequency response correction Yes
High-pass filter* (HPF) 10 –150 Hz
Low-pass filter* (LPF) 11 – 20 kHz
Analogue input impedance (RCA) 10 kOhm
Frequency range of power amplifier 10 – 50 000 Hz
Signal to noise ratio, min 90 dB
Total harmonic distortion index (THD), max 0,02 %
Intermodular distortion index (IMD), max 0,03 %
Operating supply voltage in vehicle network (+12V)
Syandby current 2 А
Fuses 2 x 20 А
Overheat control Yes
Output fixed bias protection Yes
Short circuit protection Yes
Operational temperature range –40 ... +80 оС (up to the protection operation)
Dimensions(H x W x D) 431 x 248 x 55 mm
Weight 5 kg

*factory settings can be changed by the user.

Our company follows the policy of continuous development and product improvement. Therefore technical specifications and amplifier construction can be changed without prior notification.

Power amplifier manual

The firmware program for DSP can be found here

The firmware program of DSP for bridging can be found here

Free version of archiver is available on the official web-site

See more about "SigmaStudio".

Please, visit our web store to purchase the introduced products

Online Catalog