ЦАПы — ONIX Beta XI2

The Beta XI2 is a portable dongle combining a USB DAC with a headphone amplifier, made by ONIX, a British audio brand established in 1979 whose current products come from a partnership with Shanling. It follows the Alpha XI1 dongle, is slightly longer and wider than that model, and adds a pair of miniature vacuum tubes that can be switched into the output stage. Launch pricing was USD 349, and the warranty covers the DAC and amplifier sections for one year.

Key specs that matter

Two Cirrus Logic CS43198 chips perform the conversion, with PCM decoding up to 32-bit and 768 kHz and native DSD512. The amplifier stage combines four BUF634 buffers with two OPA1662 op-amps, and the tube stage uses two JAN6418 tubes. Maximum output is 550 mW into 32 ohm from the 4.4 mm balanced jack in either mode. From the 3.5 mm single-ended jack the figures are 45 mW in low gain and 180 mW in high gain with transistors, or 37 mW and 152 mW with tubes. In transistor mode the single-ended output measures 0.0006% THD+N at 2 V with a 124 dB signal-to-noise ratio and 0.3 ohm output impedance, and the balanced output reaches 0.0008% at 4 V, 128 dB and 0.6 ohm. The body measures 69.8 x 39 x 14 mm and weighs 45.3 g.

Engineering and use context

The two JAN6418 tubes sit inside the aluminium housing, and two side windows let their glow show through. With the tubes engaged, distortion rises to 0.06% on both outputs, while the signal-to-noise ratio stays at 122 dB single-ended and 127 dB balanced, and the single-ended output impedance is unchanged. In balanced tube mode the low-gain level drops to 52 mW. A 22 mm monochrome OLED display shows playback format, volume and settings, and three multifunction buttons control the menu. Five digital filters can be selected, and gain switches between high and low. Signal and power arrive through a single USB-C socket that works in both UAC 2.0 and UAC 1.0 modes. A gold-plated OL1 cable with silver-plated copper conductors is supplied.

Pairing

Compatible hosts are Android and iOS devices as well as Windows and macOS computers, all connected through the USB-C input. Headphones can be connected through the single-ended jack or the balanced one.

Alternatives

The ONIX Alpha XI1 is the earlier and simpler dongle DAC of the brand, also built on two CS43198 chips but without tubes, rated at 500 mW into 32 ohm balanced and priced at USD 109.