Questyle CAS192D Digital to Analog Convertor
Questyle CAS192D Digital to Analog Convertor
True is best. Questyle Audio CAS192D is the world’s first USB DAC support true DSD mode.
The Questyle Audio CAS192D is upgraded from Questyle’s previous flagship model. The “D” stands for “(True) DSD”. The Questyle Audio CAS192D is designed to process DSD files in their native format without conversion to PCM.
Now there are two ways to transfer DSD signal to a DAC through a USB port: DoP and True DSD (also called Native DSD).
So far most brands who claim that their DAC supports DSD, as it turns out use DoP (DSD over PCM). In the DoP, PCM protocol is used to transfer the DSD file, PC and media player pack DSD file into PCM and then send to DAC for converting. It can be treated, actually, as “fake DSD”, as it still utilizes PCM to process the signal. The advantage is, it’s easy design (media player can pack DSD file into PCM),cost is low (same hardware as in PCM version), but the most serious shortage is, obviously it can’t fully express DSD features.
The Questyle Audio CAS192D is totally different. When it’s used to transfer DSD signal, it doesn’t pack DSD into PCM, instead, its software directly sends the DSD source code to CAS192D. There are two individual circuits in CAS192D, one is PCM signal channel circuit with 4-pins, the other is True DSD channel with 3-pins. Once the Questyle Audio CAS192D detects the input signal is DSD, its hardware circuit will be automatically switched to the True DSD channel to process DSD signal. In this circumstance, all the digital filters become invalid, the volume control becomes invalid as well, the whole system is processing DSD files in their native format.
The power supply section is upgraded as well. Customized Plitron toroidal transformer, Schottky rectifier, 22pcs Nichicon 2200uF FG capacitors, 22 groups of individual power regulators, all to ensure each section a stable and purified power. The DAC chipset uses 4 levels of digital filters and power regulation.
Furthermore, Questyle Audio’s 3X Clock USB Asynchronous transmission structure is maintained in the CAS192D design. And in PCM mode, the Questyle Audio CAS192D still provides 5 switchable digital filters, in which the IIR (MP) filter eliminates Pre-Ring from pulse wave. The Upsampling button is switchable between on and off, allowing convenient sound performance comparisons. The DAC chipset is Wolfson WM8741, with an improved LPF and buffer stage, changed to DALE resistors, to achieve overall a more stable performance and more purified sound.
The Questyle Audio CAS192D aluminum chassis is produced by precise CNC tooling machine. The upper cover and bottom chassis “mutual bit” structure design, provides CAS192D with stable heat, excellent control of sympathetic vibration and excellent shielding of RFI/EMI radiation.
▪ Wolfson flagship DAC chip WM8741，with which the innovative application circuit design is officially affirmed by Wolfson.
▪ DAC power supply utilizes 4 levels voltage-regulating.
▪ Specially designed OPA627+BJT hybrid LPF stage eliminates TIMD (Transient Intermodulation Distortion).
▪ WIMA FKP2 capacitors are used in LPF and buffer to ensures a clean sound .
▪ IIR (MP) Digital filter eliminates the pre-echo from pulse wave; it is switchable for 5 different kinds of filters and is convenient for users to compare different sound to find their favorite one.
▪ Dual Clock integral upsampling technology: two ultra-low phase noise clocks makes upsampling integrally; the upsampling is optional for start or shut.
▪ Specially designed toroidal transformer by Plitron has the separate digital and analog power supply.
▪ Schottky rectifier, 22 PCS of 2200uF Nichicon FG audio capacitances and 20 sets of separate regulators are utilized in the whole device.
Input and output section
▪ Standard Coaxial, Optical and USB input, PCM 192KHz/24Bit.
▪ 3X clock structure for USB asynchronous transmission, which refers to3 independent ultra-low phase clocks respectively control USB data transmission, and data of integral multiples of 44.1KHz and 48KHz transmission, together with asynchronous technology, perfectly reduce Jitter.
▪ The dedicated USB driver guarantees the stability and compatibility of the whole system.
▪ XLR and RCA Output is optional.
▪ XLR output utilizes Neutrik connector.
Digital Input: USB Input, Optical,Coaxial, PCM 44.1K-192K/16-24bit signal
PCM 44.1K-192K/16-24bit and True DSD Source Code
Digital Filters in PCM mode: 5 groups of switchable IIR (MP) and FIR (LP) digital filters
Digital Filters in DSD mode: None
DAC Chip: WM8741
PCM mode up sampling: Dual clock integral up sampling; optional for open or shut
Supportive OS @ USB Input: Win XP,Vista,Win7,Win8 and MAC OS
Music Player @ USB Input: Any player
Kernel Stream Mode Supported by USB Data?: WASAPI，ASIO，KS
Output Interface: RCA , XLR
Output Amplitude: RCA :2.44Vrms,XLR :4.88Vrms
Frequency Response: DC-77.5 kHz（192K sample rate, +0,-3dB）
THD+N: < 0.005%
SNRRCA:115 dB,XLR:116 dB
Max External Dimension: 330*300*55MM