Audiolab launched the 6000A integrated amplifier with a DAC based on the ESS ES9018 chip, Bluetooth, phono input and headphone amplifier. The amplifier has four digital inputs on board – a pair of optical and coaxial, capable of receiving a signal of up to 24 bit/192 kHz. Three digital filters are provided: fast decay, slow decay and minimum phase. The amplification is designed in class AB, the device produces 50 W per channel at 8 ohms. Power is provided by a 200 VA toroidal transformer with capacitors with a total capacity of 60,000 pF. In the circuit design, much attention was paid to shielding the preamplifier section, protecting it from interference. In the headphone amplifier, the feedback works on current. The MM phono preamplifier circuit is made on field-effect transistors.
The Audiolab 6000A amplifier has three operating modes: the main one, where both the preamplifier and the power amplifier function, the Pre-Power power amplifier mode for connecting, for example, to a home theater system, and the Pre mode, in which the device operates only as a preamplifier.
The integrated amplifier is very similar to the older model 8300A – the same set of rotary controls on the front panel, the same oval OLED display. However, it has a much richer functional equipment. In addition to the standard analog linear inputs, there is a built-in MM phono preamplifier built on JFET transistors. The set of digital inputs includes optical and coaxial, there is also a wireless Bluetooth module with support for the aptX codec. All physical digital inputs support a PCM stream with parameters up to 24 bit / 192 kHz. The front panel also features an output from a separate headphone amplifier.
A lot of effort has been put into the Audiolab 6000A’s digital circuitry to ensure that it delivers the same level of sound quality as a high-quality standalone DAC. As usual, Audiolab has used the reference ES9018 Sabre32 DAC chip, with its 32-bit architecture for digital-to-analog conversion using HyperStream ECC technology, and its Time Domain Jitter Eliminator to ensure ultra-low noise and wide dynamic range.
No other company knows more than Audiolab how to make the most of all this technically superior, yet complex, DAC technology. If the circuitry that surrounds the ES9018 is not of sufficient quality, the resulting sound can seem a little cold and even hard; however, if treated correctly, the level of musical expression that this chip extracts from a digital signal can be incredibly captivating. The original Audiolab M-DAC, which earned widespread acclaim, was one of the first home audio components to use the ES9018 chip back in 2011, and the company has been relentlessly refining its digital-to-analog conversion implementation ever since.
The Audiolab 6000A power amplifier stage operates in class AB and delivers 50 W per channel into 8 Ohms, with maximum currents of up to 9 A even into the most difficult loads. The discrete output stage uses the CFB (Complementary Feedback) topology, providing excellent linearity and temperature stability, while the idle current remains independent of the temperature of the output transistors. A large 200 VA toroidal transformer, with 4×15,000 μF storage capacitors (60,000 μF in total), helps the amplifier precisely control the speakers, providing an excellent dynamic range.
The preamplifier section is implemented by the designers as simply as possible to preserve the purity of audio signals, while from the line inputs they go to a precision analog volume control. It covers a range from -80 dB to +8 dB in 2 dB or 1 dB steps (the step increases with increasing volume). Much effort has been put into optimizing the physical routing of the connections inside the Audiolab 6000A to protect the sensitive preamp section from the effects of noise. All this, plus the use of independent low-noise power supplies for the critical stages, helps to realize such high sound quality that this model rivals significantly more expensive analog amplifiers, even without taking into account the impressive digital capabilities of the Audiolab 6000A.
Recognizing the vinyl renaissance, Audiolab has included a high-quality MM phono preamp in the 6000A – a low-noise, JFET-based amplifier with precise RIAA equalization. In addition, more and more people today use headphones to listen to music, so Audiolab has created a dedicated headphone amplifier with current feedback circuitry. The wide bandwidth and high slew rate ensure dynamic, detailed and engaging playback with all types of headphones – another plus for this well-equipped integrated amplifier.
Audiolab 6000A Specifications
Output Impedance – 120 Ohms
Output Power – 2 x 50 W into 8 Ohms
Frequency Response – 20 – 20,000 Hz | THD – 0.0004%
Signal-to-noise ratio – 110 dB
Inputs – analog RCA (5), digital optical (2), digital coaxial (2)
Outputs – analog RCA (pre-amplifier)
Dimensions, mm – 445x 65 x 300
Weight, kg – 7.8.
