Questyle Audio CMA800i User manual

CMA800i
解码耳放一体机
用户手册
www.questyleaudio.cn
CMA800i
DAC with Headphone Amplifier
www.questyleaudio.com

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Contents
Check List .....................................................................................
Front View .....................................................................................
Rear View ....................................................................................
Current Mode Amplification Technology .......................................
True DSD Technology ...................................................................
Standard USB Asynchronous transmission......................................
PCM Version Digital Filters ...........................................................
PC System Requirement ..............................................................
Install Driver Program under Windows OS ...................................
Core Audio Stream Technology ...................................................
Setup Core Audio Stream on JRiver Media Center ......................
Setup DSD on JRiver Media Center .............................................
Installation in MAC OS .................................................................
Specification .................................................................................
Cautions ........................................................................................

In May 2014 the Munich High-end Audio show, CMA800i is officially launched to
international market. Since design stage, CMA800i is set as an integrated DAC,
Headphone Amp and Pre-amplifier questing for most Hi-end sound quality.
CMA800i headphone amplifier section follows Questyle flagship headphone amp
CMA800R current mode amplification patent design, most components used are
same. Ultra low distortion as to 0.00026%, ultra wide bandwidth up to 850kHz (+0,
-3dB), working in pure Class A status under Super-current, all these features
enables CMA800i amplification be most outstanding among all the all-in-one
models.
CMA800i DAC section, PCM version it adopts USB Asynchronous transmission 3X
Clock structure design, support 192kHz/24bit both USB and SPDIF input/SPDIF
output, more important is it support True DSD format digital to analog converting.
Different from current DoP (DSD over PCM) format, CMA800i drive program will
send DSD source code directly to DAC section for digital to analog converting, its
hardware is specially designed with DSD channel to process DSD signal in its
original format ,strictly comply with standard SACD format. Same as CMA800i,
CMA800i adopts Wolfson WM8741 DAC chipset with 4 levels of digital filters and
power regulation. In PCM version it’s designed with IIR(MP) digital filters to
eliminates pre-ring, while in True DSD version all digital filters are invalid.
Pre-Amplifier output is one more specific feature for CMA800i. Many brands, when
they design a all-in-one model, they use the headphone amplifier circuit loop to
support pre-amplifier function in the meanwhile, on the sake of cost. But CMA800i,
only care how to achieve best sound performance, is designed with totally indepen-
dent pre-amplifier, even the power supplier supporting pre-amplifier circuit is total
Check List
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independent located. Volume control adopts a ALPS27 potentiometer working in
pure analog format, supporting remote control, as well more suit for supporting
active speakers.
A good sound performance require Hi-end components to support. CMA800i is
assembled with suitable Hi-end components like DALE military resistors, WIMA
capacitors, Nichicon FG capacitors, customized Plitron Toroidal transformer, Neutr-
ik connectors...etc. Aluminum chassis is specially CNC tooled into “mutual-bit”
structure, 10mm thickness cover, reduce the CMA800i natural resonance to lowest
level. Even the feet is pure aluminum material, tooled by CNC machine, it can be
switched to 3-feet triangle structure or 4-feet quad structure as per user’s favorite.
CMA800i
Power Cord
CD-ROM
Remote Control
CMA800i User Manual
Test Report
User Manual of Remote Control
1pc
1pc
1pc
1pc
1pc
1pc
1pc

① USB input (type B)
② SPDIF output
③ SPDIF input
④ Left channel RCA input in “External” mode
⑤ Right channel RCA input in “External” mode
⑥ Pre-amp XLR output for Right channel
⑦ Pre-amp XLR output for Left channel
⑧ Pre-amp RCA output for Left channel
⑨ Pre-amp RCA output for Right channel
⑩ 230V/115V voltage switch button
AC power supply
Front View Rear View
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① Standby Button.
② PCM mode indicator.
③ DSD mode indicator.
④ USB input indicator.
⑤ SPDIF input indicator.
⑥ USB/SPDIF input switch.
⑦ 6.35mm Jack plug A.
⑧ 6.35mm Jack plug B.
⑨ Remote Control Sensor.
⑩ Digital filters. In PCM mode, digital filters are switchable by remote
control. In DSD mode, digital filter says “NO”
Internal &External switch. When the switch bar is moved to “External”,
CMA800i is used a pure headphone amplifier; when it’s moved to
“Internal”, CMA800i internal DAC works and becomes an all-in-one
model.
Volume control
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USB IN
DIGITAL HP AMP
EXTERNAL INPUT
SPDIF
OUT L
CH
R
CH
R CH STEREO OUTPUT L CH
L
CH
R
CH
SPDIF
IN
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3
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910
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511

(Global PCT No.: PCT/CN2014/075775)
Current Mode Amplification, means the amplification is processed in Current
version, instead of Voltage version.
Current Mode Amplification, same as Voltage mode, also take transistors as ampli-
fication components. But the amplification circuit loop is totally different from that in
voltage mode, in the whole closed-loop all the capacitors in between those transis-
tors which affects speed and bandwidth are working under ultra-low impedance, so
it can easily achieve large bandwidth and ultra low distortion.
Low distortion and large bandwidth is what all amplifiers want to achieve. Only with
ultra large bandwidth and high speed processing can an amplifier wonderfully
process sudden pulse wave signal, and achieve real playback of music signal
speed and transparency.
Traditional Voltage mode amplifiers always cause a Transient Intermodulation
Distortion (TIMD), which brings a harsh “metallic sound”, badly destroyed the
sound.To eliminate TIMD, designers usually adopts feedback circuit loop (low
feedback, partial feedback or negative feedback) in hardware but these don’t totally
settle the problem, and cost is very high.
While Questyle gives up the traditional voltage mode format, designed with a
“Current Mode” amplification. When the components is working in Current mode,
amplifier Slew Rate (SR) achieves a linear increase as input signal amplitude
increases, it is in proportion to input signal amplitude. When it’s input with large
amplitude signal, Current Mode amplifier SR is much larger than traditional Voltage
mode devices, it can totally eliminate TIMD and ensures large amplitude signal and
low distortion real playback.
Current Mode Amplification Technology
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(China Intellectual Property Office Patent No. 201520211945.X )
Unlike other DACs that claim DSD support, yet in actuality provide DoP (DSD over
PCM), the Questyle Audio CMA800i accepts the DSD bit-stream directly from your
computer, bypassing your computer’s audio processing and digital volume control
as well as the Questyle Audio CMA800i’s digital filters, to provide True DSD, the
way it was meant to be heard, without requiring expensive difficult to install propri-
etary connectors, or as is the case with DoP breaking up the bit-stream into 16bit
packets and compressing them into a PCM data-stream and then uncompressing
them at the other end, buffering them, then reassembling the bit-stream so that it
may be sent to the DAC as DSD, all of which requires an extreme amount of
processing at both the computer end and the DAC end to perform in real time
True DSD（Direct Stream Digital）Technology
WM8741
DSD
PCM
DSD
DAC
PCM
DAC
DSD
PCM
True DSD DAC
PCM
DSD
PCM PCM

(China Intellectual Property Office Patent No.201520212711.5)
Generated signals from piano, percussion and guitar contain a large amount pulse
wave. Studies of the sound psychology indicate that our ears are very sensitive to
the pre-ring of impulse wave. It makes music incoherent and unnatural. The
pre-ring, brought by FIR (finite impulse response) digital filters used in traditional
digital to analog conversion, can be tested and heard very easily. The Questyle
Audio CMA800i has the most advanced IIR digital filter, which completely
eliminates the pre-ring from the impulse wave and brings the most natural sound.
dCS is an example of a company using IIR digital filter technology.
Different digital filters have different impulse responses and group delay, creating
different subjective listening experiences. On the front panel of CMA800i, there is a
DFR button providing 5 different digital filters for user to choose. Among the five
digital filters, the pulse responses of IIR and FIR are totally different. Different FIR
or IIR digital filters have different frequency responses. The digital filters are
switchable based on user’s favorite.
Vibrating objects in nature produce a sound wave which has similar features to the
IIR digital filter. There is no pre-ring before the vibration and the vibration amplitude
decreases gradually after the vibration.
PCM Version Digital Filters
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CMA800i IIR digital filter pulse response CMA800i FIR digital filter pulse response
When the sample rate is as low as in 44.1k or 48k, the 5 digital filter options of the
Questyle Audio CMA800i will be:
- IIR Apodisting
- IIR soft-knee
- IIR Half-band
- FIR Apodisting
- FIR Half-band
When the sample rate is as high as in 88.2k, 96k or 192kHz, the 5 digital filter
options of the Questyle Audio CMA800i will be:
- IIR Apodisting
- IIR soft-knee
- FIR soft-knee
- FIR Apodisting
- FIR Brickwall
The Questyle Audio CMA800i will divide the user’s configuration of digital filters
into high and low groups and memorize the sample rate.

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PC System Requirement
(If you don't use the USB input function of CMA800i, you won’t need the following
settings)
1) Operating System
The Questyle Audio CMA800i driver and hardwares support Win XP, Vista, Win 7
32Bit/64Bit, Win 8 of 32Bit/64Bit operating systems. For Apple products, later
versions of the 10.5.7 Mac OS are supported, no special driver software need to be
installed.
2) Player Software
The Questyle Audio CMA800i doesn’t require special player software. Any
executable player software (including video program) on a PC can send music data
to CMA800i for decoding. For Windows system, we recommend JRiver Media
Center to experience the full benefits of True DSD.
3) File Type
Music file format playing is the province of the player software. As long as the player
software supports the playing of stereo music files, CMA800i can decode it. For
JRiver Media Center users, it can perfectly support DSD, FLAC, WAV, and MP3
files.
4) The dedicated driver of CMA800i
The Questyle Audio CMA800i can support Microsoft operating systems Win XP,
Vista, Win7 32bit/64bit, Win8 32bit/64bit. USB3.0 required for support the output of
24bit /192K USB Audio data.
5) PC Configuration Requirements
Win XP (SP2 or SP3), Vista, Win7 32bit/ 64bit or Mac OS 10.5.7 or later operating
system. At least one USB port. A quality USB2.0 high-speed cable of type A plug to
type B plug. We suggest using a high-quality USB cable to ensure the stability and
reliability of data transmission and guarantee the best performance from the
Questyle Audio CMA800i.
6) Other Requirement
Communication between CMA800i and PC is real-time and therefore requires
some available resources from the PC hardware and software platforms during
playback. Insufficient resources (available memory or processing) will cause
instability, as well as abnormal status from the CMA800i. In such cases, try running
dpclat.exe (http://www.thesycon.de/deu/latency_check.shtml ) to check whether
the Ethernet, Wireless LAN or other equipments have affected the working of
CMA800i.

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Install Driver Program under Windows OS
Driver installation is required for the Questyle Audio CMA800i to be recognized by
a PC. In this example we will use Win7 32 bit operating system to demonstrate the
installation process.
1) Power on the Questyle Audio CMA800i
2) Plug the USB cable into the Questyle Audio CMA800i and into an available USB
port on the PC, connecting PC and the Questyle Audio CMA800i.
3) Open the DSD-1.05-(CR) folder on the included CD and click “ ”to
access to installation interface
4) Here are tips on the installation:
Click ”Install”.
Click “Next”.

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Core audio stream technology is generally used by high-fi audio workstations. It
incorporates ASIO, KS and WASAPI, all of which are supported perfectly by the
Questyle Audio CMA800i.
According to PC general audio processing procedures, all sound from applications
and systems is processed by SRC, going through the lengthy system of processing
and hardware layer transmission, and then is output to the external device. The
output data is totally different after all those procedures. To output the pure, original
and “bit-perfect” data, we must open a high-speed and dedicated channel for the
audio device, that is the core audio stream technology.
5) Click "Finish" and restart the PC.
6) Installation on Win XP, Vista OS is the same. No more explanation here
Core Audio Stream Technology
The Questyle Audio CMA800i supports ASIO and KS on Win 7, Vista, Win XP
systems, and supports WASAPI audio output on Win7 32Bit/64Bit, Win8
32Bit/64Bit operating system. For example, when you enable WASAPI + Exclusive
Mode between the Questyle Audio CMA800i and player software (like
Foobar2000), you can't control the volume through system controller, the sound
from the system and other applications (such as Email Alerts) will not be heard
through the Questyle Audio CMA800i, because the system has opened the core
audio stream channel for the Questyle Audio CMA800i and the audio data is sent
directly get to the DAC of the Questyle Audio CMA800i with high-speed.
If you don't set the output to the core audio stream, you will find the sample rate
shown on the Questyle Audio CMA800i is different from that of playing the original
music, and it is locked at 48K or 44.1K. When you finish the following settings, you
will find that the shown sample rate is the same as that of the original music playing,
which is telling you that the PC is putting out "bit-perfect" data now.
Let’s take Win 8 32bit operating system as example, to see how to setup JRiver
Media Center.
1.Download and install
1)Click the website http://www.jriver.com/download.html , click “Windows Down-
load” to download the JRiver Media Center 19.
2)Install JRiver Media Center 19.
2.Import music
1)Open JRiver Media Center, find the “import...” item from “Tool” option, click it,
choose “Configure Auto-Import”. Then click “Next” .
Setup Core Audio Stream on JRiver Media Center

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2) Click “Add...”, then next screen click “Browse”, find the file where the music
stays, then click “OK” to complete it.

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3. JRiver output setup
1) Under “Tool” option there is an “Option” menu, click it to enter sub menu.
3）With above setting, now CMA800i can play the music files from PC (exclude
DSD files);
1) Open JRiver Media Center, click “Tool”--”Option”, entry the sub menu.
2) In “Audio” --”Audio Device”, choose “ASIO for C-Media USB Device [ASIO]”
3) Click “Device settings” menu to find ASIO setting sub menu, click “Open Driver
Control Panel”, bit-depth choose “24/24 bits”, Latency “10ms”, click “OK”.
Setup DSD on JRiver Media Center

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4) In “setting” menu, click “DSP & Output format”
5) Remove all the selected options, then close it.
6) In “Bitstreaming: None (recommended)” menu, choose “Custom..”

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Installation in MAC OS
7) Click “DSD”, then click “OK”.
8） With above setting, CMA800i can now both plays DSD and PCM (APE, WAV,
FLAC, etc) files from PC;
For Apple MAC Operation System developed later than OS 10.5.7 ,they are
compatible with USB 2.0 High-Speed firmware, so it doesn’t need to install the
Questyle Audio CMA800i driver program. The Questyle Audio CMA800i works
with standard USB Asynchronous transmission.
When PC is USB linked to the Questyle Audio CMA800i, user needs to set sound
output as “Questyle Hi-end USB Audio”.

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Specification
Headphone Amp section (External Format)
Gain 11.8dB (3.9times)
Max Output Power（Po）180mW（7.5Vrms）@300Ω；1W@32Ω
THD+N 0.00026%@1kHz，Po=100mW，300Ω
0.00050%@1kHz，Po=50mW，32Ω
SNR 118 dB
Frequency DC-200kHz(+0，-0.5 dB)；DC-850kHz(+0，-3 dB)
Sensitivity 2.2Vrms
Input Internal DAC output, or External RCA input,switchable
Output Dual 6.35mm Standard Stereo Jacks
DAC and Pre-Amp section
Input SPDIF input and output, USB Type B input
Signal
SPDIF input and output: Standard PCM 44.1-192K/16-24bit
USB: PCM 44.1-192K/16-24bit and DSD Source Code following
standard SACD format
PC OS to match USB input Win XP,Vista,Win7,Win8 and MAC OS
Digital Filter PCM Mode:Switchable IIR(MP) and FIR (LP)
Ture DSD Mode: No filter
USB supported Kernal stream WASAPI，ASIO，KS
Analog Output Balanced (XLR) and unbalanced (RCA)
Nax output amplitude XLR：8.6Vrms；RCA：4.3Vrms
THD+N < 0.005% for both XLR and RCA
SNR >107dB for both XLR and RCA
Whole device
Voltage 100-120V or 220-230V switchable
Power Consuming 13W
Dimension 330*200*55 mm
Note: Data listed above are collected from Audio Precision AP2722 testing.
The information in this manual is subject to change without notice.
All right reserved. ©2016 Questyle Audio Technology Co.,Ltd.
Code: EN-UM004-800iV170710
Cautions
1. Do not use your CMA800i in a hot or humid environment.
2. Unplug your CMA800i in lightning weather or during a long period without using.
3. Do not have your CMA800i covered by anything.
4. Only the specified or manufacturer-supplied power cord can be used for your
CMA800i.
5. Clean your CMA800i with a piece of dry cloth or the special cleanser.
6. If your CMA800i fails to work, please contact your dealer or manufacturer.