Cayin RU7 dongle amp/1bit-DAC
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 Minimize Interference
To minimize interference, RU6 circuitry
is split into TWO 6-layers PCB, with
digital and analog circuit
installed in separate boards.
Safeguard signal integrity, make
sure the noise from reference clock
and DSP will not bleed into
amplification circuit.
Functional Diagram for RU7 1-Bit Dongle DAC
Low Power Consumption
Compatible with Common Platforms
Discrete resistor network is a low-power DAC circuit when compare to other highly integrated DAC chipset, minimize 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
