You may know, with countless digital audio-related data, that it is imperative that digital audio devices have clock signals.

 The digital audio devices express very delicate audio signals using a digital data comprised of ‘0’s and ‘1’s, and although the digital audio devices can also transmit the audio signals to other devices, the digital audio signals have to be converted eventually to analogue signals to reach us because the digital data cannot be felt or understood by our senses. This process is called a Digital to Analog Conversion, and the digital data in this process is converted to an analogue signal in response to a signal (clock signal) where ‘0’ and ‘1’ are repeated at a predetermined time interval.

 Theoretically, although a perfect clock signal must repeat ‘0’ and ‘1’ at a predetermined time interval, the perfect clock signal unfortunately does not exist in this world. All clock signals have a time error, and a more perfect analogue signal can be made when the number of errors grows fewer.

 The time error, that is, the accuracy of clock is measured and managed not in the digital domain, but in the analogue domain such that the digital audio may be called a part of the analogue audio domain. A method to more easily and more clearly understand and feel the accuracy of the clock is to experience the sCLK-EX, which is a clock module of SOtM.

 If you have ever experienced at least once the sound changes in an audio system incorporating an sCLK clock module, there will be no need for further deliberate explanation of what results can be obtained when the sCLK-EX clock module is used. It is on another level in terms of function and audio quality.

 The sCLK-EX can be used for all digital devices that require clock signals such as a DAC, a USB host card, a CD player, a PC main board and a LAN controller. The sCLK-EX can simultaneously use four (4) clock outputs so that one single sCLK-EX board can be used for various frequencies including the system clock, LAN port clock and USB clock in your PC.

 Furthermore, the device can be used synchronously with a high precision clock such as a rubidium clock by using the Master clock option.

 You can easily reach a completely new sound stage with a single sCLK-EX board. You are requested to please experience a different dimensional world brought by sCLK-EK, which is an upgraded version approved by already advanced technology and sound.

Key Features

  • Custom designed ultra low phase noise oscillation circuit
  • Isolated differential clock signal distribution
  • Four outputs clock
  • Wide operating voltage input range
  • Ultra low noise regulator circuit
  • External master clock input
  • Clock control input


Internal reference clock
  Custom designed ultra low phase noise oscillation circuit
  Isolated differential clock signal distribution
Clock output
  Isolated clock output : U.FL connector x 4
  Supply matching board for connecting target board
Single clock frequency for interface system
  sCLK-EX12 : 12MHz
  sCLK-EX25 : 25MHz
  sCLK-EX48 : 48MHz
  sCLK-EX22/24 : 22.5792MHz / 24.576MHz selectable by SEL0 input
  sCLK-EX45/49 : 45.1584MHz / 49.152MHz selectable by SEL0 input
  Optionally other frequencies available
Dual independent clock frequency for digital audio system
  sCLK-EX1412 : 14.318MHz, 12MHz
  sCLK-EX1448 : 14.318MHz, 48MHz
  sCLK-EX1425 : 14.318MHz, 25MHz
  Optionally other frequencies available or selectable by SEL0, 1 input
Triple independent clock frequency for mother board & interface
  sCLK-EX142512 : 14.318MHz, 25MHz, 12MHz
  sCLK-EX142548 : 14.318MHz, 25MHz, 48MHz
  Optionally other frequencies available or selectable by SEL0, 1 input
Quad independent clock frequency for mother board & interface
  sCLK-EX14252612 : 14.318MHz, 25MHz, 26MHz, 12MHz
  sCLK-EX14252648 : 14.318MHz, 25MHz, 26MHz, 48MHz
  Optionally other frequencies available or selectable by SEL0, 1 input
Clock control input
  Isolated control input connector x 2
  Non isolated control input x 7
External master clock input : Optional
  Input frequency : 10MHz (Optionally other frequencies available)
  Isolated 50Ω external clock input : U.FL connector x 1
  Isolated 75Ω external clock input : MCX connector x 1
  Differential clock signal input & internal distribution
Power input
  Input Voltage : 9Vdc(Standard)
                          Optional 12Vdc
                          Optional 6.5Vdc ~ 8.5Vdc
  Operating current : 1A >
Power output
  All outputs use an ultra low noise regulator circuit
  5V, 0.5A x 1
  3.3V, 0.5A x 1
Power regulator circuit
  Custom designed ultra low noise regulator circuit x 3
  Standard ultra low noise regulator circuit x 1
  Active noise canceler circuit
  Audio grade film capacitors
  Audio grade tantalum capacitors
Operating environment
  Operating temperature range: +10 ~ +30oC
  Storage temperature : 0 ~ +40oC
  Operating & storage humidity : 10% ~ 90%


Yes, it is possible to customize the sCLK-EX by your request. To do this,  you should give SOtM or the store  where you will purchase the correct information about the clock which you would like to replace to sCLK-EX.

To do this, high technical information should be required to check about the correct frequency, type of component, required voltage and other specifications and details to change your current clock system to sCLK-EX. If you are not proficient in such information or doing the process, please ask SOtM or the store from where you will purchase to do it. Otherwise, we highly recommend using the sCLK-EX combo packages such as ‘tX-USBexp + sCLK-EX48, tX-USBhubIN + sCLK-EX12, tX-USBexp + specific maind board + sCLK-EXXXXXX, etc)

And if you ask the customization of the sCLK-EX or your main board to SOtM or the store where you will purchase, some labor charge and  a round trip shipping fare should be required. 

 If the main board doesn’t work normally after the customization, SOtM or the store will take care of 50% of the repair cost . 

sclk-ex_tx-usbhubasus-b150m-plus-stcom_1 sclk-ex_tx-usbhubasus-b150m-plus-stcom_2 sclk-ex_tx-usbhubasus-b150m-plus-stcom_3 sclk-ex_tx-usbhubasus-b150m-plus-stcom_4

You can choose the wire between stranded UPOCC copper or stranded UPOCC silver, and the length choice could be made among 30cm, 50cnm or 100cm.

Normally the copper wire sounds relatively calm and neat, and the silver wire is relatively open and more delicate. 

  • 7N UPOCC Copper cable : it brings a very clean sound without having any distortion in sound.
  • Stranded 7N UPOCC standard Copper cable : it brings a clean sound with much musical nuance without having any distortion.
  • Stranded 7N UPOCC silver cable :Compared with copper wires, it brings more detailed and dynamic scenes, and brings the distinctive bright and precise sound propensity of silver wires.
  • Stranded 7N UPOCC Copper cable :Compared with the standard copper wire and silver wire, the sound character is middle of their propensities, it bring very detailed musical nuance.

Depending on which type of cable is used, it effects sound in your system hugely, so select the proper cable type for your system according to your sound taste.

The standard power cable which is supplied as a basic accessory is stranded UPOCC copper wire.

Single clock output Qty. 4 1
Dual clock output Qty. (EX. 22.5792MHz <-> 24.576MHz) 4 1
Internal reference clock isolation Yes No
Output clock isolation Yes Yes
Master clock input Yes No
Maser clock input isolation Yes X
Differential clock system Yes No
Frequency configurable by F/W upgrade Yes No

The super clock module, sCLK-EX has been improved a lot from sCLK, even though it is already very good quality clock module, especially the expressions in the ultra low range has been much improved providing much diversity of textures and transparency and also the mid-low range expressions get become significantly plentiful.

And connecting master clock to the sCLK-EX, you are able to make the best possible sound in your audio system.

No, even though you have the master clock input for the sCLK-EX, you don’t need to connect the external master clock device all the time. You can keep the master clock input for the future use if you currently don’t have the external master clock device. We are planning to build the good quality master clock device soon~.