DACs — Ayre Acoustics QX-5 Twenty

The QX-5 Twenty is a digital hub from Ayre Acoustics of Boulder, Colorado, combining a streaming network input, a multi-input DAC, a digital volume control and a headphone amplifier, all housed in one enclosure. The Twenty suffix belongs to the series of upgraded Ayre models, and the listed price starts at USD 14,000.

Key specs that matter

An ESS ES9038PRO chip does the conversion, timed by a crystal oscillator developed jointly by Ayre and Morion. Ten digital inputs are fitted - Ethernet, asynchronous USB, two AES/EBU, three optical and three coaxial S/PDIF. The USB port takes PCM from 44.1 to 384 kHz at 16, 20 or 24 bits and DSD64 or DSD128 as DoP, while the optical, coaxial, AES/EBU and network inputs cover PCM up to 192 kHz with DSD64 as DoP. The line outputs deliver 4.5 V RMS balanced or 2.25 V RMS single-ended, and the headphone outputs reach 9.0 V RMS balanced or 4.5 V RMS single-ended. Operating draw is 60 W. The case measures 438 mm wide, 330 mm deep and 95 mm high and weighs 7.3 kg.

Engineering and use context

All analogue circuitry after the chip is discrete, fully balanced and runs without feedback. Ayre applies its own Minimum Phase digital filter with single-pass 16x oversampling rather than the filters built into the ESS chip. The output stage uses the Ayre Diamond topology, and gain stages use the Ayre EquiLock circuit. The S/PDIF input works asynchronously, so the internal clock rather than the source sets the timing. Level is set digitally across 100 steps of 1.0 dB, and Ayre states that full resolution of the source file is kept down to -60 dB. A linear analogue power supply feeds the circuits, the mains input passes through the Ayre Conditioner filter against radio frequency interference, and the boards use high-speed circuit board material. The AyreLink bus lets the unit communicate with other Ayre components in the same system.

Pairing

With the volume control and a high-level balanced output on board, the QX-5 Twenty can be wired straight to a power amplifier with no preamplifier in between, and Ayre offers a matching power amplifier within the same Twenty generation. The high-voltage balanced headphone output is aimed at demanding headphones, while the network input allows the QX-5 Twenty to work as the streaming front end of the system.

Alternatives

The Ayre QB-9 Twenty is a smaller DAC from the same Twenty generation that takes its music data over USB.