AfterDark. Project ClayX GIESEMANN Word Clock x 10M Master Clock for dCS

Optimised Clock for
Grade vs Phase Noise@10Hz
Audiophile 10M Master Clock

The development of Giesemann Word Clock x 10M Master Clock for dCS system

AfterDark. developed a new Master Clock for dCS user who want to try to maximise the performance for the dCS system with Word Clock on 44.1kHz or 48kHz. The Giesemann will included extra 10M Master Clock out for connecting audiophile switch such as UpTone EtherREGEN accepting 10M Master Clock signal bypassing the internal clock.    



The Giesemann Word Clock x 10M Master clock will have following features:

  1. Three independently outputs on 75ohm BNC connectors. Each group may be preset to a different clock frequency. 
  2. For dCS system: Output 1: 44.1KHz / Output 2: 48kHz / Output 3: 10M Master Clock
  3. AfterDark. Project ClayX Linear Power Supply build in to optimised the performance for Giesemann Clock, the power inlet is from Furutech NCF. 
  4. Customer can made to order and choose the grading on Giesemann OCXO Clock from Queen to Giesemann EVA
  5. Carbon Fiber shielding and machines aluminium chassis fitted with AfterDark Audiophile WoodMAT to reduces vibration.




Giesemann OCXO Features 
The product uses the selected audio grade OCXO, and through long-term calibration to select and install equipment with excellent stability.

  • OCXO that employs with qualitative measure equipment.
  • OCXO is enclosed and covered with Dynamat Extreme Corporation (Made in USA) which is used to stabilize and minimize heat separation,  addition EMI material from KEMET EMI Shielding is placed on top of OCXO,  the outer layer is covered with real leather to isolate the heat factors for maximizing OCXO performance . 
  • Alu material + Carbon Fiber material front and backplate, solid anti-vibration. In addition, due to the thickness used, 3mm / 6mm Carbon Fiber material material with plate can provide solid EMI/ magnetic coverage.
  • Advanced instrument Symmetricom 5125A calibrated with plotted characteristics. The phase noise, and Allen Derivation defines different grades of the OCXO. 
  • Audio Note Silver Solder
  • Duelund AC0.4 Silver Premium Audio Cable (Silver in Cotton / Oil impregnated) (Handmade in Denmark)
  • Ultra High Quality Large Factor 5151 SC Cut OCXO, very low phase noise and frequency stability compared to others small size OCXO specification 
  • SC Cut refers to stress compensated (SC) cut crystal resonators, which is more advance on performance of Frequency Vs Temperature changes, longer Crystal Aging. The pro is expensive to made and size is larger then normal OCXO. 
  • Then Large Factor size 5151 is around 5cm x 5cm dimension vs small factor 3cm x 2cm, 2 times bigger with better phase noise performances. 
  • OCXO are available in tailor made on various audio frequencies on special request. 



Level selection value
The OCXO installed in the product can calibrate the products used in industrial equipment for a long time, and use equipment with good characteristics. In order to optimally select the audio clock, we comprehensively evaluate with Symmetricom Flagship 5125A to analysis the phase noise characteristics and short-term stability (Allen dispersion) that can be determinate the OCXO grading accordingly.

The OCXO installed in this product uses a stable OCXO unit that has been calibrated for several months. In order to make the best choice of OCXO. We are conducting a comprehensive evaluation of phase noise characteristics and short-term stability (Allen dispersion) during detailed inspection. 

The final product will final measured and fine tuned with Keysight 53220A with reference to Atomic Clock , GPSDO. 



Quality of OCXO is determined by Phase Noise at 1Hz / at 10Hz
Phase noise: -119 to -113 dBc / Hz or lower at 1 Hz offset (Grades) -137 dBc / Hz or lower at 10 Hz offset


GRADE Phase Noise@ 10Hz Phase Noise@ 1Hz
PRINCE -131 -100
QUEEN -132 -103
KING -134 -107
Emperor Signature  -138 -110
Emperor CROWN -140 -113
Emperor DOUBLE CROWN -141 -117
Emperor TRIPLE CROWN -142 -118
Emperor Giesemann -143 -120
Emperor Giesemann EVA -145 -121


Allan variance short-term stability reference value

[Emperor Giesemann EVA]TAU = 1sec 2.50E-13 or less(0.00025ppb / s)

[Emperor Giesemann] TAU = 1sec 2.78E-13 or less(0.00028ppb / s)
[Emperor Triple Crown] TAU = 1sec 3.8E-13 or less(0.00038ppb / s)


[Emperor Giesemann EVA] indication on Phase Noise at 10.0Mhz (dBC/Hz) by FlagShip Symmetricom 5125Aimage.thumb.png.9738cb1f23359ba20f12d1139983e56b.png


[Emperor Giesemann EVA] indication on Allan Deviation by FlagShip Symmetricom 5125A


Technical index

  1. Ultra-low phase noise OCXO 10MHz oscillator
  2. Belden 75ohm BNC cables 1m x 3 units 
  3. Output 1: 44.1kHz / Output 2: 48kHz and Output 3: 10 MHz x 3 outputs at square wave
  4. Output impedance: 75 ohm 
  5. Body size: W235mm x D310mm x H110mm 
  6. Weight about 4.6 kg
  7. 2 years free maintenance warranty
  8. Design and specifications are subject to change without notice
  9. Made in Hong Kong 



Type: OCXO Clock

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Discount Code: CYBER