Questyle Audio CMA800P User manual

CMA800P
Current Mode Pre AMP
POWER
INPUT VOL
BAL UNBAL MUTE WORK
CMA800P
Current Mode Pre AMP
POWER
INPUT VOL
BAL UNBAL MUTE WORK
CMA800P
电流模前级功率放大器
用户手册
www.questyleaudio.cn
CMA800P
Current Mode Pre-Amplifier
www.questyleaudio.com

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Features .......................................................................................
Check List ....................................................................................
Front View ....................................................................................
Rear View ....................................................................................
Instructions ...................................................................................
Technology ..................................................................................
Specifications ...............................................................................
Contents

Thank you for selecting Questyle Audio CMA800P Pre- Amplifier. We are sure it will
provide you with countless hours of uninterrupted musical bliss. At Questyle Audio
it is our goal (our “Quest” so to speak) to provide elegant, precision manufactured
audio products with a no-compromise approach to sound. Whether you intend to
drive a conventional amplifier, a headphone amplifier or a headphone amplifier with
an integrated preamp, the Questyle Audio CMA800P will produce a sound that is
rich and detailed with an extended and more controlled bass, greater dynamics and
authority, as well as, high frequencies that exhibit an airiness and musicality, that
simply cannot be found elsewhere.
The Questyle Audio CMA800P employs an all discrete, all Class A architecture
implementing Questyle Audio’s patented "Current Mode Amplification" technology,
producing no measurable TIMD while boasting THD levels of less 0.00021%
across the entire audible spectrum with a linear bandwidth of over 100kHz. With
performance like this, the Questyle Audio CMA800P can easily challenge all
pre-amps in current production.
In our unending quest for audio perfection, even the chassis is an active audio
component, the Questyle Audio CMA800P employs heat-leaking aluminum cases
to maintain proper temperature control, and shield from unwanted external EM
radiation.
To insure precise and reliable production the Questyle Audio CMA800P undergoes
strict levels of quality control. To this end, all metalwork for and final assembly of the
Questyle Audio CMA800P is carried out at Foxconn, under the highest standards of
operation, and each Questyle Audio CMA800P carton box contains a test report
made by AP2722, detailing its performance during final testing.
Features
Check List
CMA800P
Power Cord
User Manual
1pc
1pc
1pc
02 03
- Patented Current Mode Amplification, 0.00021% ultra-low distortion and
ultra-high bandwidth amplification
- Balanced (XLR) and Single Ended (RCA) inputs
- Customized Plitron toroidal transformer
- Nichicon 2200uF FG Audio capacitors
- WIMA capacitors
- All discrete transistors working in a pure Class A configuration
- ON/OFF Anti-Pop Noise protection and DC protection
- Each device has its AP test report attached with the User Manual

① Function selection button
②AC Power indicator
③Balanced input indicator
④Unbalanced input indicator
⑤Mute indicator
⑥Status indicator: it is on for working normally.
⑦Volume control
04 05
Front View
CMA800P
Current Mode Pre AMP
POWER
INPUT VOL
BAL UNBAL MUTE WORK
12 3 6 7
4 5
Rear View
11
①Right channel balanced input
②Right channel unbalanced input
③Left channel unbalanced input
④Left channel balanced input
⑤Right channel balanced output
⑥Right channel unbalanced output
⑦Left channel unbalanced output
⑧Left channel balanced output
⑨220V/110V voltage switch button. Please make sure the indicated
voltage confirms to local voltage.
⑩AC power supply
AC power ON/OFF Switch
BAL R
STEREO OUTPUT
BAL L
UNBAL R UNBAL L
BAL R
STEREO OUTPUT
BAL L
UNBAL R UNBAL L
1
2
3
6
7
8
910
4
511
DIGITAL HP AMP
EXTERNAL INPUT
R CH STEREO OUTPUT L CH

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1)Current Mode Amplification
(Global PCT No.: PCT/CN2014/075775)
Questyle Audio’s Current Mode Audio Amplification features the use of transistors
to amplify, with a disaggregate structure designed in, to wit: voltage input and
output, while the core amplification takes place in the current domain operating in
a pure class A state, and allowing the output stage (OPT) to be changed to either
class A or AB. It is completely different from the traditional voltage mode amplifier,
in the structure of the amplification circuit. Capacitance between the transistors,
which affect the speed and bandwidth, operates at a very low impedance, and the
full-power bandwidth of the entire amplifier loop is very close to the bandwidth of a
closed loop, while the Slew Rate grows linearly with the input signals, together with
a strong and speedy negative feedback loop (the speed of the circuit is hundreds
of times faster than that of conventional voltage amplifiers). All these attributes are
quite different from that of a traditional voltage amplifier. It not only eliminates the
TIMD, it also easily achieves amplification with a wide bandwidth and ultra low
distortion.
2)Rigorous Test and Sound Control
During the development stage, we first use AP (Audio Precision) to analyze signal
data for objective test. Once the desired performance specs are achieved, exten-
sive listening tests are undergone to determine the sonic qualities that the objective
tests can’t measure. Subjective tests go hand in hand with objective tests, aiming
to achieve a perfect feeling as well as unbeatable specifications. Each CMA800P
will be tested by over 30 factors of specification before being shipped out, and copy
of the test report will be put into carton box, while another copy will be kept as a
record.
Technology
1) HIGH/LOW GAIN switch of CMA800P
Open the top cover of CMA800P, put the 4 switch buttons on the PCB to LOW for
LOW GAIN, and switch them to HIGH for HIGH GAIN.
2) LOW GAIN is recommended for matching with STAX SR-009.
When STAX SRM-727 is used as a power amplifier, it is necessary to open its top
cover and switch to “DIRECT” mode, bypassing the volume control for STAX
SRM-727.
Instructions

08
Specifications
Gain Gain High: 6dB
Gain Low : 0dB
Max Output
Amplitude
13Vrms, full balanced mode
6.5Vrms, unbalanced mode
SNR 131 dB, full balanced mode
124 dB, unbalanced mode
THD+N
0.00021%@1kHz, 10KΩ, full balanced mode
0.00023%@1kHz, 10KΩ, unbalanced mode
Frequency
Response
DC-100kHz(+0, -3 dB)
(Built-in Input Low-pass Filter)
Input
Impedance
2.9K Ω
Input XLR Stereo
RCA Stereo
Output XLR Stereo
RCA Stereo
Work Status
Pure Class A
Voltage 100-120V or 220-240V
Power
Consumption
9W
Dimension 330*300*55 mm