Cayin RU7

Fully Balanced Resistor Networks

Discrete 1-Bit DAC for DSD Format

Purposively designed micro-miniaturized 1-bit DAC circuit from discrete components   Convert digital signal to analogue signal through a fully differentiate 4-ch

DAC architecture

The 1-Bit DAC circuit is a resistor network composed of 128 pcs (4 x32) high

 precision Thin Film Resistors, this is closely resemble to the discrete DAC of

our N7 DAP

The output of the resistor network will go through a 3-level active LPF and

then converted to single-ended signal for volume adjustment. 

Dual amplifiers in parallel,  providing 4-CH high power  Balanced Driven output   The second phone amplifier  is a parallel unity gain  inverting phase amplifier

An impressive upgrade in  phone output power : 3.5mm SE, 160mW @32Ω 4.4mm BAL, 400mW @32Ω

Shared Line Out Conveniently Connected

The shared line out function will  configure the 3.5mm or 4.4mm  phone output into fixed voltage  output (bypassing volume control): 3.5mm Single-ended, 1.2Vrms 4.4mm Balanced, 2.4Vrms

The line out voltage are carefully  selected to retain as much details  and dynamic of the 1-Bit DAC with  minimum noise and distortion. 

Enable you to connect the RU7 to  portable/desktop amplifier or home  audio system and used it as an  miniature 1-Bit DAC 

Discrete Volume Control

Discrete Resistor Network DAC circuit is very demanding on incoming data integrity,  we recommend users to keep the digital volume of mobile phone at full output to  safeguard the quality of audio digital signal. 

When off-the-shelf analog  volume options cannot meet high  precision, low noise, low power  consumption requirement of RU7,  we developed our own discrete  resistor network volume control 

100 steps volume control through  3 segments of resistors and  switching relays *,  offer precise control over  a wide volume range,  satisfy even the need of  most sensitive IEM users: Segment 1: 1-49 Segment 2: 50-79 Segment 3: 80-100 

Outstanding Digital Audio Capability with

User Selectable All-to-DSD

RU7 supports PCM up to 384kHz and native  DSD from DSD64 to DSD256. Its Audio Bridge will receive different audio format and  go through high precision signal enhancement.

All digital audio signal will convert to designated DSD format (DSD64/DSD128/DSD256) before feeding to the discrete 1-bit DAC circuit.

Dual PCB to Minimise Interference

To minimize interference, RU6 circuitry  is splited into TWO 6-layers PCB, with  digital and analog circuit  installed in seperate  boards.

Safeguard signal integrity, make  sure the noise from reference clock  and DSP will not bleed into  amplification circuit.

Low Power Consumption

Compatible with Common Platforms

Discrete resisotr network is a low-power DAC circuit when compare to other highly integrated DAC chipset, minimise power drain from mobile source.

Redesigned amplification  circuit increase  output power dramatically  while maintains the overall power drain at 100-110mA

Low power consumption allows RU7 compatibles with the following digital audio sources:  • Android  based mobile devices • iOS and  iPad OS mobile devices • macOS computers • Window 7/8/8.1/10 computers • Digital Audio Players with USB Audio output

An All-Rounder

Bundled Protective Case

Soft and tender handmade  magnetic leather case  Custom make for RU7,  precise cutout  offers tight-fit protection  and elegant presentation  Two circular metal plate with  adhesive tape pad are included.

A Compact and Nimble Powerhouse

Weight:  25g , small enough to slip  into your smallest pocket

Dimension: 66*24*12 mm

Package List:  ① RU7 Dongle DAC  x1 ② Type-C cable  x1 ③ USB A to C adapter  x1 ④ User Manual  x1 ⑤ RU7 Protective Case x1