giesemann reference sfp optical isolator pa1 on sale

AfterDark. Project ClayX Netgear GS105 x Giesemann OCXO Video Switch for Netflix and 4K YouTube

Netgear Units
Grade vs Phase Noise@10Hz

The development of Cascade Netgear GS105 x Giesemann OCXO Video Switch for Netflix and 4K YouTube 


We received some customer asking for better switch for Netflix and 4K YouTube, they requires to have better picture quality and demand high speed in 1000Mb to provide the smoothness and better picture quality in large OLED. They are trying to isolate, separate the switch independently for video and audio switch. 



This Netgear GS105 x Giesemann OCXO may be the very 1st switch in the world, which build-in OCXO at this sizes. Thanks you to the latest tecnhology and circuit design build by AfterDark's R&D!!!

Therefore, we started to modified some switch to fullfill the requirement for "Videophiles". We modified a well known Netgear ProSafe GS105 network switch. There is some special reason to choose this switch. It is well design, small factor in demension, very low heat and it is good to apply modification on power section on CPU, again most important is to bypass the clock section on the motherboard, so all the ports on the switch would benefit with OCXO, provide the best picture quaility for demand applications.   

The Cascade SE Edition

  • Since we cascade the Buffalo GS-BS2016 in last Project ClayX, we planned to release the cascade version for "Videophile"
  • The Single and Double version will comes with AfterDark. AudiophileMAT Carbon Fiber 3mm at the top. This can provide the best EMI protection for OCXO and motherboard. 



The size is so small in dimension, the size is around 9.5cm x 10cm x 3cm. So, the most difficult part is how we feed the OCXO module inside and enhance the power section on CPU. The new Giesemann OCXO module was redesigned and much smaller in size to be placed inside the Netgear GS105. All the modification is hand solder with cares.  

c.thumb.jpg.fa052f151b4506225addb2c332aae3f4.jpgSetting of Cascade is very possible and flexible for the small square dimension. Looks really nice with Carbon Fiber. 


The OCXO module is at the right bottom, it provide the 25Mhz output to the motherboard

For the power requirement on CPU section, the CPU requires 1.2V DC. For the OCXO module, this requires 3.3V DC. All the power supply is enhance with LT3045 and TI's TPS7A4701 LDO Voltage Regulartor

Question and Answer

Will this OXCO modified switch good for Audiophile for audio?

  • Yes, we test this unit on both Audio and Video, it can enhance audio perfromance too.
  • The soundstage is much wider and mirco dynamic increases, the sound is much smoother, analog and laid back. 
  • We found the noise at the background is reduced on Video, so the back colour is more clean. 

Why this OCXO switch can improve picture quality?

  • The CPU inside the switch is bypassing the internal clock, using the OCXO clock will provide better phase noise and reduce jitter in signals. Thus, the picture quality is greatly improved, darkness and black color will vivid nicely. 
  • The linear power supply with ultra low noise is apply independently to CPU, OCXO and motherboard, it provide the best isolation for each devices. Much details representaion on video can be achieved, especially one dark background
  • The black become much darker with graduation on grey levels, it will be more impressive in large screen or projectors. 

What is the DC voltage requires?

  • One 5V 2.0A Linear Power Supply (LPS) is recommended 

Why Netgear GS105? 

  • This is well know to smooth sounding in normal retail version. The design is well implemented, five port in one direction, and power plug at the back. The motherboard is at 5th edition, very stable and easily to implement the mods. 
  • Size and low heat is another factor, for customer put inside the carbin and work fine without ventilations.
  • Commercial grade from Netgear, some good features like ProSafe, Jumbo Frame, QoS, utlra long MTBF Failure time (3,197,945 houes) are extra bonus
  • Non-Blocking swiching architecture for maximum throughput for all 5 ports at 1G Copper Wire Speed 
  • No configuration necessary - perfect for entertainment such as ROON, Netflex, YouTube. 
  • Standard - Based Design which ensure intercoperability with any standards based network, 
  • Fast boot up time at 3 seconds. 
  • Fanless design means zero added noise wherever its located, make it ideal for audiophile enviroments. 
  • Metal Case, very durable and rugged. 


Why does the mod changed it to 5V DC input, while the normal verison is 12V?

  • The power section on the motherboard is all bypassed and upgraded to better power supply and regulators. 
  • For example, the CPU 1.2V, OCXO 3.3V, motherbaord is all changed to linear power supply instead of DC-DC switching

What is the maxmium throughout speed for this 1000Mbp switch?

  • Bandwidth is 10Gbps, so all 5 port can support 4K video/ Netflex, retrieving data at the same time
  • All the port is supporting Jumbo Frame Support (Up to 9K packet size) 

What is the maxmium tempature for full modified Netgear GS105?

  • The is the lastest version called V5, it is complaint to Energy Efficient Ethernet (IEEE802.3az), much less heat even all ports is playing 4K Video
  • The temparature is aound 38 degrees on full loading 
  • We believe when it is less temparture, the the Video is less noisy and sounding will become much smoother. 

Is there a fan inside the switch?

  • Pressive cooling for CPU and no fan is required

Is there Traffic Prioritization for Video on NetFlex and YouTube?

  • This vesion V5 is build in to cope with prioritize mission-critical applications such as video Support IEEE 802.1 p and DSCP-based QoS for delivering data based on priority and type

How long is the boot up time?

  • The modified OCXO switch can boot up in 3 seconds. It works plug and play immediately. 

What is the quality of OCXO inside the switch?

  • The Giesesemann OCXO Clock - Prince Grade is build inside as stardard option for Netgear GS105 switch 

Why OCXO is become a startard for audiophile switch?

  • The quality on Phase Noise and Allan Derivation is much better performed when compared to other TCXO, FETMO clock.
  • The sound will be more smoother without digital feelings, more organic music and details  
  • The all-in one design will give you more space for Cacade x 2 Double or x 4 Quad switch for extreme audiophiles. 
  • The single unit version will outperform any non-OCXO switch in huge mergins. 


This OCXO switch is easily implemented and can improve Video and Audio quality on all NetFlex, YouTube in few minutes. Just plug and play, it will boot up in 3 seconds time. 




Type: OCXO Clock

Related Items

Let's celebrate!

AfterDark. is delighted to have successful shows at HighEnd Munich 2024.🙂

Please feel free to share the discount code with friends.We love to hear more music lover to enjoy this great product. 

Discount code: PA1