Предусилители — Audio Analogue Absolute

The Absolute is a reference line preamplifier from Audio Analogue, the Italian brand of AF Group Srl, and part of its ABsolute line designed by Airtech, which forms the company's reference range. Its intended partner is the ABsolute Monoblock, a pure Class A mono power amplifier, and the circuit is fully differential and dual mono from the power supply onward.

Key specs that matter

There are three RCA inputs and two balanced XLR inputs, all with 47 kOhm input impedance, and two RCA and two XLR outputs. Gain is 5.58 dB at the unbalanced outputs and 11.62 dB at the balanced outputs. Frequency response extends to 200 kHz at -0.5 dB with no attenuation. Balanced output noise is 20.4 µV from 20 Hz to 80 kHz and 7.7 µV A-weighted. Referred to 1 V RMS, signal to noise ratio is 93.8 dB from 20 Hz to 80 kHz, 98.3 dB from 20 Hz to 22 kHz and 102.3 dB A-weighted. Standby consumption is 0.5 W. The preamplifier measures 480 x 140 x 385 mm and weighs 22 kg.

Engineering and use context

The power supply filters the mains with inductors to reduce noise and uses two transformers of about 50 W each, both shielded electrostatically and magnetically and coated in resin. Each stage sits on its own board, the layout is fully dual mono from the supply onward, and the preamplifier boards are mechanically shielded from the power section. The circuit uses no global feedback and remains differential from input to output. Volume is controlled by a relay-switched resistor network, which Audio Analogue chose for lower distortion than semiconductor volume chips, and input switching is also done with relays that disconnect unused inputs completely. The gain stage is Audio Analogue's proprietary SeGeSTA design. Oversized military-grade through-hole resistors and audio-grade capacitors are used throughout, a microcontroller manages the functions, and internal wiring and the power cable come from Airtech. The balanced gain is twice the unbalanced figure in voltage terms, reflecting the differential output stage, and the two pairs of each output type allow bi-amping or a subwoofer connection.

Pairing

The ABsolute Monoblock Class A mono amplifiers are the intended partners, connected through the balanced outputs. With two XLR and two RCA outputs, the preamplifier can also drive a pair of stereo amplifiers in a bi-amped system, or one amplifier plus an active subwoofer.

Alternatives

The Audio Analogue Bellini is the line preamplifier of the brand's Anniversary line.