The A2D2 is a compact converter, powered via its USB‑C connection (PSU not included), that works with your own Wi‑Fi network to send audio from a source device to any other device on your network — things like computers, tablets, smartphones, smart TVs and smart speakers. The A2D2 offers direct integration with AirPlay, Chromecast and Sonos. While there’s a more elaborate setup routine for working with Amazon smart speakers, step‑by‑step instructions are provided.
Working at up to 192kHz/24‑bit quality, FLAC, MP3 and WAV codecs are supported. Audio goes into the A2D2 through a pair or RCA phono connectors, with another pair providing analogue audio pass‑through. The manufacturers claim that the device works with pretty much everything that puts out analogue audio and they mention playing your vinyl over the system. Note that you can’t just plug in any old turntable because most require a separate RIAA preamp (https://sosm.ag/q-do-i-need-an-riaa-preamp), but you may have a suitable audio output on your hi‑fi amplifier or preamplifier.
The A2D2 seems happy to accept headphone‑level signals, so if no other source is available you can always use that. There’s also a headphone mini jack on the side of the unit for local listening, as well as a USB 3 port and an RJ45 Ethernet socket for direct connection to your network. A rotary volume control is located on the front panel. Small LEDs on the side of the unit indicate powering, and blue LEDs flash until a Wi‑Fi connection is established.
Once you’ve gone through the install routine (about half a dozen steps), for most networked devices you can find the A2D2 by entering http://A2D2.local on your device, at which point you can select standard or high‑sample‑rate playback. Further instructions are available for connecting to smart speakers. There appears to be quite a long buffering delay between feeding in the audio and hearing it played back, which I suspect is intentional, as this would give the system plenty of time to avoid dropouts caused by marginal Wi‑Fi connections.
While the A2D2 is intended as a high‑quality consumer device for sending audio over wi‑fi, there are potential studio applications too.
While the A2D2 is intended as a high‑quality consumer device for sending audio over Wi‑Fi, there are potential studio applications too, including sending mixes to alternative listening systems around the house to check for compatibility with consumer devices. I have no complaints regarding the audio quality, and providing you are not too far from the Wi‑Fi router when setting up, the setup procedure seems very smooth.