|
Description:
QA350 MOD V2+ is an all-in-one portable SD card HiFi wav
music player. It has a high quality DAC and headphone
amplifier integrated into its tiny body. The headphone
output is able to drive most 16-300 headphone in the
market.
It is upgraded from QA350 with huge improvements regardless
of the balance of frequency and timbre, resolutions,
accuracy, low and high frequency extension and dynamic
range.
QA350 MOD V2+ upgrades the headphone amplifierfrom MAX9722A
to AD8397 by taking advantage of AD8397 s Rail-to-Rail and
high output current technology. In order to push the
performance of QA350 platform to the maximum potential, the
engineering team put a lot of efforts in optimizing power
supply systems and PCB, and more than 10 versions of PCB
were tested to get the final PCB design.
QA350 MOD V2+ employs 7.4V Li-polymer battery normally used
on aircraft models. This type of battery has very low
internal resistance and high discharge rate. The momentary
discharge current is able to reach couple of amperes easily.
This gave QLS design team the opportunity to get rid of the
voltage boost circuits and voltage reversal circuits that
are very common to see in the portable players. Therefore
QA350 is able topresent the music with enhanced bass and
transient response, as well as ultra-low high-frequency
noise and full of details.
The good thing kept on
QA350 is the single threaded real time audio play program
with SD card. This unique technology is QLS s guarantee to
be HiFi. It is without any interrupt to steam the music
files, other control functions are carried by another
separated microprocessor. It achieved extremely high
accuracy on the time sequence when streaming music files
from the SD card. Moreover a special customized 11.2896 2ppm
TCXO with jitter lower than 10PS is used as the main
sampling clock.Thus the whole system reached our goal on the
recovery of musics.
Specifications:
- Support format: 16bit
44.1K WAV (the same with CD ripping and file format).
- SD/SDHC up to 32GB with
FAT32, 90 folders up to 900 music tracks
(Please use TOSHIBA original card, other brands of sd
card may be a problem.)
- Firmware upgradeable
- Digital output chip:
CS8406.
DAC Chip: Wolfson WM8740.
LVP: AD8656.
Headphone Amp chip: AD8397.
- Output:
- Digital Coaxial RCA
- Digital Optical(round)
- Analog Line out: 2V (RMS), frequency response
20Hz-20KHz, SNR> 100dB, Distortion <0.002%
-
Headphone out: 500mW/16 ; 250mW/32 ; 49mW/300 ;
Frequency response: 20 Hz-20Khz;
THD + N (total harmonic distortion plus noise): <0.003%,
matching impedance: 16 ohm --- 300 ohm
- Battery Type: 7.4V
Li-Po battery of Model General Specifications, maximum
size: 55mm * 31mm * 16mm; the capacity is usually among
800-1100mAH.
- Battery life: 4 to 6
hours.
- Charging time: 1.5-3
hours (when charging, playing music can available
powered by the external power supply)
- Charger: 110-240VAC,
800mA/S, balanced 2 cell charger.
- Power: 150-180mA (LED
backlight OFF), 200-300mA (LED backlight ON), 9VDC
external input.
- Remote control
- Dimension: 135mm * 78mm
* 27mm (excluding the output socket, switch, button,
etc.)
150mm * 78mm * 30mm (with all the sockets, VR button,
switch, button)
- Package size: 235mm *
135mm * 55mm
- Single Weight (with
battery): 0.3kg
Packing Weight: 0.75kg
About WAVs...
WAV files are the favourite format choice
of people who can't bear the sonic difficiencies of the
lossy compressed MP3 format yet want to store, preserve and
playback treasured CD collections from their computer hard
disk drives.
Up until now, these people would simply be
content to use their computer as their main Hi-Fi source
component.
Whilst excellent at converting CDs to WAV
files, the PC / Mac is still not the ideal music plackback
device. The majority if PCs don't have the best
powersupplies and are absolutly packed with noisy,
interference inducing components. Multiple noisy fans buzz
away constantly and due to components fighting over limited
resources, "pops" and stutters on the audio are not
uncommon.
In these days of hugely expensive utility
bills, the electricity consumed in putting a computer to use
for considerable periods just for music playback is also
quite considerable as is wear and tear to the hardisks.
Reasons why the QA-350 is a better music transport than a
PC...
- Silent
(no moving parts)
- No pops
stutters or audio glitches (assuming that WAVs were
extracted with love by EAC)
- Uses
nowhere near the amount of energy that a PC needs
- Far more
compact than even the smallest laptop PC
- Useful
remote control functionality
|
Internal PCB board:
(In order to improve the quality and sound quality, components are
subject to change without notice.)
If you are an
electronics&HiFi enthusiasts, and if you need this product's
circuit schematics by PDF file, please
contact to Clark:
cxqmcu@cxqmcu.com for get
, (Please make sure that the files can not be used for
commercial purposes, and also can not be share in network,
and you are already has this product or will buy it.)
|
