QLS Audio, HI-FI/HI-END Audio,DAC,WAV Player

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QA690--Full Digital Hi-Fi Stereo Amplifier


QA690 ( Without USB ) USD $620.00
QA690 ( With USB ) USD $710.00  ( All Exclude shipping cost ) ( in Stock )
How buy it: Click here       Warranty: Click here

  • QA690 is a Hi-End Full Digital Stereo Amplifier, It is based on the QA100 with improvementon the circuit, We spent over 3 years on developing and continuing optimizationthrough testing more than 10 major hardware version. This is a true competitor to most of the Stereo Amplifier, complicated power supply systems and clock circuits.
  • Our target: ^Perfectly and accurately recovery for the music recordings, and deep dark background ̄.
  • QA690 is able to drive 4Ω@160W-8Ω@100W2 way bookshelf and floor standing speakers smoothly with accurate, transparent, high dynamic range and excellent transient response sound style.
  • QA690 designed as open loop digital circuits, thus there is no stable problem even in driving speakers with very low impedance. Moreover DSP technology is employed to correct the expected deviation on the final outputs that made a significant improvement for the amplifier¨s line output characteristics.

24bit/192KHz wav and DSD Support

  • QA690 supports up to 24Bit / 192KHz and DSD64 / 1Bit / Stereo (DoP input or USB) .

QA690(With USB) Also have a XMOS USB Bridge to Computer

  • The QA690 (With USB) also is have an asynchronous High Speed USB to digital audio interface that extracts the highest possible audio quality from computer audio sources.
  • The QA690 (With USB) is have High Speed USB 2.0 input data connection C Sampling rates up to 192 kHz and word lengths up to 24 Bit are supported.
  • Great care was taken in the design of the QA690(With USB) to isolate the noisy computer/USB environment from the digital audio output. The USB receiver and processing are powered by the computer, while the output line drivers are powered by a separate isolated linear power supply.
  • The QA690 (With USB) USB is designed to work with both Apple Macintosh and Windows PC computers. Microsoft Windows PC¨s require the included Windows driver which works with Windows XP, Vista and Win7 / 8/ 10.


  • High quality sampling clock reform circuits.
  • Input: RCA Coaxial*2, Optical*1, Analog Line in*1, USB*1[Only for (QA690 with USB)]
  • Digital format: 16bit to 24bit, 32K to 192K Stereo (sampling rate and bit adaptive), DSD64(DoP input or USB)
  • Power Stage chip: TAS5624 *2
  • Master Volume: 0 ~ 80; L/R Volume Trim: -5 ~ +5; TREBLE Trim:0~5, BASS Trim:0~5 .
  • Use Low Jitter Crystal .
  • Total hamornic distortion (-2.5dBFS, 8 Ω) <0.02 %.
  • Dynamic Range, a-weighted 101 dB.
  • S/N ratio, a-weighted: 101dB.
  • Channel separation: 97dB.
  • Frequency response, audio range (20Hz - 20kHz) +/-0.5dB,8 Ω
  • Power: AC 90~120V and AC 200-240V selectable
  • Speaker Impedance range: 1.5Ω -16 Ω
  • Power output: 4 Ω 160W x 2CH;  8 Ω 100W x 2CH
  • Dimensions: 215mm x 315mm x 100mm
  • Weight: 5KG

Internal PCB board: (In order to improve the quality and sound quality, components are subject to change without notice.)


The following items are included with your Order:

  • QA690 ( Without USB ) USD $620.00

  • QA690 ( With USB ) USD $710.00 ( All Exclude shipping cost ) ( in Stock ) 

At the time of purchase, please indicate the following: Your couftry's voltage specs.

Payment methods 1: Direct remittance to PAYPAL, Our paypal account: cxqmcu@cxqmcu.com

QA690(Without USB) Amplifier (Exclude shipping cost) USD $620.00  

QA690(With USB) Amplifier (Exclude shipping cost) USD $710.00


Shipping by DHL/EMS Express to United States, Canada, Japan, Australia, India, Indonesia, Korea, Malaysia, New Zealand, Singapore, Thailand USD $50.00

Shipping by DHL/EMS/EUEXP Express to all European countries and Brazil, Israel, Kazakhstan, Russia USD $70.00   
If the list have not include your country, Please send email to cxqmcu@cxqmcu.com or clark_chen@yahoo.cn and ask.

  • We will send good by DHL/TNT/EMS Expres, and we will declare the sending for gift with a low value(For example: USD $100.00), to reduction reciever side to pay tax or try to avoid reciever side to pay tax.
  • If the list have not include your country, Please contact us for get your shipping by E-mail.cxqmcu@cxqmcu.com / clark_chen@aliyun.com / 315392961@qq.com
Payment methods 2:  You can go directly to our EBAY purchased online stores: http://www.ebay.com/itm/302422397364 

Payment methods 3: 
You alse can pay to our bank accout:

Our Bank of China Account:
    A/C NO: 4766938-0188-129144-0     IN A/C WITH: TANG YAN 
    POST CODE: 518033

Tip: The beneficiary name should be TANG YAN , Not is QLS Electronics.
After payment,please E-mail us the your recipient name. Recipient address. Zip Code. Contact phone number.
Our Email:  cxqmcu@cxqmcu.com  clark_chen@aliyun.com  315392961@qq.com

Payment Method 4:  Wester Union

  • You can select the nearest agency for westernunion, you only need my name, city and country to send money. They accept cash and online payment .After you send it, the workers of westernunion will give you a control number, i need this control number and your full name to draw money.
  • With more than 150 years of experience, Western Union is a global leader in money transfer services. It helps consumers and businesses send money quickly and reliably,only take 5 minutes to arrive.you can visit www.westernunion.com for more details.Also it is easy to find a close agent from this link: http://www.westernunion.com/info/selectCountry.asp and please click Find An Agent .

Here is my westernunion info:

Firstname: Yan
Familyname: Tang
Address: A4-1-3B,Qianlong Xinmao Garden,Longhua,ShenZhen,Guangdong,China
City: ShenZhen
State: Guangdong
Country: China

     After payment,please e-mail us The Sender's First Name, Last Name, Total Amount, Money Control Transfer Number and address on the payment sheet, so that we can track and get the payment.
Also Please tell to us the your recipient name、 recipient address、zip Code、 contact phone number.
Our Email address:  cxqmcu@cxqmcu.com  clark_chen@aliyun.com  315392961@qq.com

ADD:Room A1502,NiuLanQian Building,MinZhi Road,LongHua Town,ShenZhen,GuangDong,China
Postalcode:518131  TEL:+86-0755-28187975  FAX:+86-0755-28187976