「RU7」
Copec Japan released a portable USB DAC/amplifier “RU7” equipped with a 1-bit resistance ladder type DAC from the Cayin brand on June 9th. The direct sales price is 44,990 yen.
Equipped with an ultra-compact 1-bit DAC circuit made up of discrete components. Digital signal is converted to analog signal by 4ch DAC architecture of full differentiation.
This 1-bit DAC circuit is a network composed of 128 (4 x 32) high-precision thin-film resistors, and is said to closely resemble the discrete structure of the Cayin N7 DAP. The output of the resistor network is converted to a single-ended signal for volume control via a 3-level active LPF.
In addition, it is said that the integrity of the received data is important for the discrete resistor network DAC circuit, and it is recommended to set the digital volume of the smartphone (connected device) to full output in order to protect the quality of the digital signal.
Native playback of PCM up to 384kHz and DSD 256 is possible. All digital audio signals are converted to DSD 64/128/256 and fed to a discrete 1bit DAC circuit.
The circuit board is divided into two 6-layer boards to minimize interference. The digital and analog circuits are mounted on separate boards.
Dual amplifiers are arranged in parallel to achieve 4ch high power balanced drive. The second phone amplifier is a parallel unity gain inverted phase amplifier. The output terminal is 3.5mm single end (also used as line output) and 4.4mm balanced, and the output is 160mW @ 32Ω when connected with single end and 400mW @ 32Ω when connected with balance. The input is USB Type-C, and the cable is detachable.
The main unit is equipped with a 0.96 type / 128 x 64 dot organic EL display. You can easily check playback information. It also has hardware volume buttons. The housing is made of CNC aluminum.
The external dimensions are 66 x 24 x 12mm and the weight is about 25g. USB Type-C to Type-C cable (with shield), USB Type-A to Type-C conversion adapter, leather case, etc. are included.
