Cayin RU7 1-bit USB “dongle” DAC and Headphone amplifier announced

Cayin has announced their new RU7 discrete 1-bit dongle DAC. Following in the footsteps of the RU6, which was based around an a multibit PCM resistor-ladder DAC, the RU7 uses a 1-bit resistor ladder, with all regular audio converted to DSD upon input.

Like the RU6, the RU7 connects via USB-C to any capable device, such as a computer, tablet or smart phone.  The RU7 has a menu button and two volume/select buttons for controlling volume and function selection, including the ability to switch the DSD upsampling rate between DSD64, DSD128 and DSD256.

Output is via an opamp-based circuit and includes both a 3.5mm and 4.4mm (balanced) connectors, the latter of which can output up to 400mA of power, enough to drive even full-sized headphones.

Much like other Cayin products I’ve tested, the RU7 has better crosstalk numbers for the balanced 4.4mm output, suggesting that this will the best one to use for IEMs and headphones.

In talking to Andy Kong, Cayin’s social media representative, he said that the RU7 drives headphones better than the RU6, though some of that may be attributable to what is powering each of them. The Ru7, like the RU6, draws 100-110 mW, which is the maximum an iPhone will output. Like the RU6, the RU7 requires an iPhone to USB-C adaptor that allows 5V output from an iPhone, such as the  OEOTG Digital Cable.

At 12 x 24 x 66mm the RU7 is somewhat smaller than the RU6 in overall dimensions, no doubt the result of the smaller resistor ladders.

The suggested retail price of the Cayin RU7 is US$286.99.