Discrete 24-Bit R-2R Ladder Resistor Network Explained The basic idea of R-2R ladder is a matched pair of two resistors, the first is "R" and the other is "2R" which has twice the value of R. To achieve 24bit R-2R decoding, Cayin need 48 pieces of resistors (23xR and 25x2R) for one channel, or 96 pieces of high precision resistors for stereo. R-2R is famous for its natural and realistic sound signature, it'll offer a very different experience to music lovers. NOS or OS Dual DA Mode Non-Oversampling: Maintain the original sampling rate of the source bitstream. Digital filter-less, no post-processing, optimised in time domain, low phase distortion and jitter, no ringing artefact. Musical with vivid emotions, sounds natural, organic and coherent. Oversampling: Increases sampling rate (upsampling) through interpolation before DA. Enhances resolution, reduces noise and improves anti-aliasing, optimised in frequency domain. Impressive details and frequency extension, clean and sharp presentation with darker background. Discrete Volume Control R-2R DAC circuit is very demanding on incoming data integrity, the digital volume of mobile phones will damage sound quality badly. When off-the-shelf volume options cannot meet the high precision, low noise, low power consumption requirements of RU6, Cayin developed their own discrete resistor array volume control. 0-99 steps volume control through 9 segments of resistors and switching relays, meet all the RU6 requirements and transparent to maintain the natural sound signature of R-2R DAC. Intuitive and Versatile Hardware volume buttons for convenient control, doubled as menu selection when entering Mode settings. 1" OLED screen displays playback information with good visibility. 3.5mm and 4.4mm phono out to fit your earphone collection. Ultimate Dual Main Boards Layout To minimise interference, RU6 circuitry is split into TWO 6-layers PCB, with digital and analogue circuit installed in separate boards. Safeguard signal integrity, make sure the noise from reference clock and DSP will not bleed into the amplification circuit. Low Power Consumption Highly Compatible Discrete R-2R is a low-power DAC circuit when compared to other highly integrated DAC chipset on the market, minimising power drain from mobile sources. USB Audio with shielded USB-C connector, compatible with a wide range of mobile, consumer electronics and computers. RU6 is compatible with the following digital audio sources: iOS and iPadOS macOS computers Windows 7/8/8.1/10 computers * Android mobiles and tablets Digital Audio Players (Requires USB Audio Output support from the DAP) *Requires to install a proprietary USB Audio 2.0 Driver developed for RU6, free to download from Cayin’s official website. High Resolution and High Fidelity High-end digital audio compatibility. PCM: supports up to 384kHZ DSD: supports DSD64/128/256 Choice of High/Low gain to enhance performance with different IEM or portable friendly headphones.