Интегральные усилители — Ayre Acoustics AX-5 Twenty

The AX-5 Twenty is a stereo integrated amplifier from Ayre Acoustics that combines a line preamplifier section and a two-channel power stage in a single chassis. Its signal path is built from discrete parts in a balanced layout, with zero feedback, an approach the company applies across its Twenty series of separates, and it has no digital section or phono input listed among its specifications.

Key specs that matter

Continuous output is rated at 125 W per channel into 8 ohms and 250 W per channel into 4 ohms, so the power figure doubles as the load impedance halves. Overall gain is 26 dB. Input impedance is 1 megohm on the unbalanced inputs and 2 megohm on the balanced inputs, which works out to 1 megohm per phase. Ayre states a frequency response reaching from DC up to 250 kHz. Power draw is 48 W in the low-current mode and 230 W when the amplifier is fully on with no signal present. The case measures 44 cm wide, 48 cm deep and 12 cm high, and the amplifier weighs 22 kg.

Engineering and use context

Volume is handled by Ayre's Variable Gain Transimpedance circuit, known as VGT, which adjusts how much the amplifying stage amplifies with no separate attenuator in the path. It offers 46 steps of 1.5 dB each. Input selection runs through a Shallco switch with solid-silver contacts. The output section uses the Double Diamond output stage developed by Ayre, and the active gain devices are paired with the company's own EquiLock circuitry. The supply is linear and analog rather than a switching design, and the whole amplifier is housed in a case of roughly the same footprint as Ayre's VX-R Twenty stereo amplifier. Through the AyreLink communication system the amplifier can exchange control commands with other Ayre components fitted with the same link, so a connected system can respond together to power and input changes.

Pairing

Because the balanced inputs present a very high load to the source, any line-level player or DAC with balanced outputs can drive the AX-5 Twenty without difficulty, and Ayre sources with AyreLink sockets can be tied into the same control loop. The doubling of power into lower impedance gives headroom for loudspeakers whose impedance dips, and the moderate gain suits sources with standard line-level output.

Alternatives

The Ayre EX-8 is a smaller integrated model from the same maker, specified at 100 W per channel into 8 ohms and 170 W per channel into 4 ohms.