As of this post, there are only two Apple Certified AirPlay Streamers featuring high-quality DAC’s. The Arcam airDAC and Myro:Air. Both streamer/DAC combos are very capable but offer different features and components. As far as streaming capabilities both offer AirPlay streaming and are compatible with devices (e.g. Windows & Android) that can stream content to UPnP DMR’s (Myro:Air has been tested with the following media types).
The first major difference between the two is the DAC, Myro:Air uses the flagship Wolfson WM8741 DAC, whereas the airDAC uses the Texas Instruments PCM5102 DAC. You can do a google search to research the differences between the two — just for reference the raw component costs are $13.42 (mouser) for the WM8741 and $6.73 (mouser) for the PCM5102 — the WM8741 offers better SNR over the PCM5102 and the WM8741 seems to have overall better performance specs.
Second major difference is connectivity, hence the reason why I choose the back side images above. Myro:Air offers both analog and digital audio outputs that run in parallel. Whereas the airDAC only offers analog RCA outs. The airDAC does offer SPDIF (Coax), Toslink Optical inputs so it can be used as an outboard DAC. The Myro:Air only offers a USB input (more on that later). The airDAC has both WiFi and hardwired ethernet port while the Myro:Air only offers a hardwired ethernet port. This is because during testing, it was found that there was better performance (less audio quality dropouts) when using the ethernet connection. Obviously, you can still stream via your device wirelessly to Myro:Air, but Myro:Air needs to be connected to your wireless router/network via a hardwired connection — it is even suggested by Arcam that you hardwire the unit for “the most reliable results”.
While Myro:Air does not offer digital inputs, it does offer a “Made for iPod, iPhone and iPad” USB port that allows you to charge your iOS device directly using your Apple sync cable (30pin or lightening). This also allows you to stream audio directly via the sync cable bypassing AirPlay all together — think of it as a dock — you get better audio quality as a result as well. The USB port is also used for firmware updates.
Third major difference, still somewhat related to connectivity, Myro:Air has a plethora of connections that allow systems to control it. Since Myro:Air is made by Myro:Control, a home automation company at heart, they wanted to offer the ability of 2-way control of the AirPlay stream, iOS devices and UPnP clients streaming to it. Myro:Air offers both a RS-232 port for integration with systems like Crestron, Control4, RTI and Myro:Link which can be used with Russound whole house audio systems that have RNET capabilities.