The development of AfterDark. Project Clay X - Netgear M4250 Audiophile Switch for Merging HAPI MKII x Giesemann OCXO

[AfterDark.]

The development of AfterDark. Project Clay X - Netgear M4250 Audiophile Switch for Merging ZMAN x Giesemann OCXO 

 

AfterDark. received a special request from Merging customer, who would like to enhance with the external 10M Clock with the latest ZMAN via RAVENNA network. We are delighed to found a possible solution after extensive reading on Merging advanced guideline and study on the Merging RAVENNA. AfterDark. will made use of the Netgear M4250 Audiophile switch or Solarflare 8522 NIC to help customer with Merging HAPI MKII and other new device using ZMAN for sound optimisation. 

 

What is special on Netgear M4250 Audiophile Switch?

• Certified to work for Merging AES67 Audio Profile
• The switch is fanless 
• Full managed switch and build in automatic configuration for VLANs
• Support PoE for power up the Merging Anubis 
• The Giesemann Clock Sync Module can be installed and enable the 10M Master Clock Input functions for Audiophiles. 
• By bypass the internel clock, and use of Giesemann Clock Sync Module (GCSM), the ultra high quality clock can be connect via external BNC port and accepting 10M Reference Master Clock.
• The PTP network protocol will apply hardware time-stamps to incoming and outgoing Ethernet frames to synchronize the Giesemann Clock Sync Module (GCSM) via the PTPv2 to performs clock lock via Merging ARS67 Audio Profile. 

 

Merging HAPI MKII audiophile customer can make use of the Netgear M4250 and activiate the AES67 Audio profile for enable the hardware time-stamps to incoming and outgoing Ethernet frames to synchronize the Master Clock via the PTPv2 for Merging ZMAN.

 

Since we bypass the internal clock of Netgear M4250 with Giesemann Clock Sync Module (GCSM) with external Giesemann 10M Master Clock , the performance will be outperforms and exceed the expectation.

 

About PTP residency time stamping

Precision Time Protocol (PTPv2, IEEE 1588) is a protocol that enables precise synchronization of clocks with a sub-microsecond accuracy across a packet-based network. PTPv2 lets network devices of different precision and resolution synchronize to a grandmaster clock through an exchange of packets across the network. The switch supports a PTPv2 end-to-end transparent clock that is used in the PTPv2 residency time stamping feature, which, by default, is enabled globally on the switch. 

 

 

 

The development of Netgear M4250 x Giesemann OCXO version: 

1. Improve the outlook which make it more like a audiophile gear
2. The device should be powered externally with audiophile grade LPS
3. The power section should be enhanced with more exotic audio capacitors
4. The Giesemann Clock Sync Module (GCSM) will be optimised to Cascade of Netgear M4250.
5. The internal wire with optimised with Duelund Silver Cable, and solder with Audio Note 
6. The chassis will be using Carbon Fiber to tailor made for fitting the motherboard at once, or there will be single version of Netgear M4250.  
7. The EMI shielding from KAMET corp. will apply to the RJ45 ports
8. Enhancement on Industrial Grade Thermal material from Shin-Etsu  (Made in Japan) will apply to CPU again.

 

Which model should I choose between two M4250 with models GSM4210PD or GSM4210PX?

• We recommended to use GSM4210PX, the two SFPs version one. 
• The SFP can supports both 1G/10G SFP+ speed, it will be future proof. 

 

Netgear M4250 GSM4210PX (1G x 8 / SFP+ 10G x 2)

 

 

 

Why use OCXO Master Clock? 

You will get an improvement in dynamic's, a lower noise floor and more natural flow in the sound.

• For us a OCXO Master Clock is one of the most important factor's in ensuring the best possible sonic platform for any hifi system!

 

• The Giesemann Master Clock is designed for high precision audio equipment to enhance the integrity of the signal, the top of the line Giesemann OCXO ensure the accuracy of the master clock prodvide a time domain reference for reading data, its transfer and decoding. As a result, the Master Clock could minimize jitter and ensure the improvement on sounding.

 

• The Giesemann EVA OCXO Master Clock is designed to generate a very accurate, ultra low phase noise 10M Master Clock signal that delivers more accurate transfer and conversion of digital signals.

 

• The addition of the external 10M Master Clock can improve the soundstage and details of the Music Server, the extraction of details from the background is just amazing and help to achieve optimal music playback with enhanced timbre, full tone, and escpecially pace, rhythm and timing. 

 

 

[The Computer Audiophile]

Very nice!

[The Computer Audiophile]

Wonder if there's a way to tie into @El Guapo's work here - 

 

[AfterDark.]

Hi! Chris,

 

The latest development from Netgear M4250 implemented a GUI interface with AES67 , a standard template for Merging RAVENNA, the coding and instruction was tested and embedded in the OS of the managed switch. This is an excellent choice for most audiophiles who likes plug and play. 

 

 

We can now just tick the box at the admin page of M4250 and enable the PTPv2 time stamp function now. According to Merging, they tested to work well with minimise user setup. 

 

For external Master Clock, the Giesemann Clock Sync Module will bypass the internal clock on Netgear. So, when we using the Giesemann External OCXO clock as Reference Master Clock. There will be huge improvement for Merging HAPI MKII.

 

When connecting multiple device with Netgear M4250 switch, the PTP setting of Merging HAPI MKII can set Netgear M4250 as Master for time stamp, so all Merging device or Roon Server from the network can be optimised when playing streaming music from Roon Server to Merging HAPI MKII.

 

 

 

Thanks and have a nice day.

 

Best Regards,

Adrian

AfterDark. 

 

 

 

 

[Erik Haas]

@AfterDark. this is very exciting news, thank you for developing this product!

 

When it comes to using this switch as a grand master clock with the Hapi MK2 and Streaming computer as a slave.   Does the streaming computer also need to be equipped with a network card that is PTP compatible?

[El Guapo]

10 hours ago, AfterDark. said:

Merging HAPI MKII can set Netgear M4250 as Master

The role of M4250 is simply a PTP transparent clock, TC. @Erik Haas the M4250 is not the boundary clock (cost issue, maybe). It cannot be the master clock in Ravenna/AES67 network. M4250 only update the time stamp when packet leave.
 

Normally the M4250 needs a local NTP server to calibrate the internal clock for more accurate time stamp. Install a ref clock module to calibrate the internal clock of M4250 surely helps offline operations.
 

@The Computer Audiophile in my recent Intel E810 project I found the M4250 still needs to change some switch settings before selecting AV template. For example the switch’s DSCP value 34 and 46 default priority were the same. Must assigned it correctly otherwise the PTP message and the audio stream would be treated equal. Usually we use DSCP 34 for audio / 46 for PTP by AES67 media profile standard. But some times I prefer using Ravenna standard 46 for audio / 48 for PTP.

 

1. manually select trust mode to DSCP

 

2. set the priority mapping correctly 

 

3. assign the proper DSCP priority

[El Guapo]

7 hours ago, Erik Haas said:

Does the streaming computer also need to be equipped with a network card that is PTP compatible?

90% condition you don’t need specific NIC for Ravenna/AES67 on computer. I tested some Realtek, Aquantia, Broadcom and Intel’s they are all good for Ravenna network. The only exception is the 10GbE on Mac has driver issue that prevent you to use Ravenna/AES67.
 

The driver in computer side don’t need hardware time stamp. Only in software mode. Computer side don’t even send PTP delay request…

[AfterDark.]

Hi! EI Guapo,

 

Thanks for your sharing. It is always good to have experts in areas of Ravenna/AES67 network to share with Merging user how to get the best setting of the Merging devices. In the last 6 months, we have been investigate with possible solution for Merging customers for external clocking. The advancement of network surprised me with PTP. 

 

We was thinking using Cisco PTP switch, but it is too expensive for us for testing. Netgear M4250 is just right for us to try. 

 

Yes, the turnaround solution to install a ref clock module, to calibrate or bypass the internal clock of M4250 is more flexible for us to get more accurate time stamp. So, it can save us some budget to purchase a local NTP server. We believe the mininise design will be the right direction. 

 

Thanks again and have a nice day.

 

Best Regards,

Adrian

AfterDark. 

 

[GryphonGuy]

On 8/4/2023 at 9:52 AM, El Guapo said:

The role of M4250 is simply a PTP transparent clock, TC. @Erik Haas the M4250 is not the boundary clock (cost issue, maybe). It cannot be the master clock in Ravenna/AES67 network. M4250 only update the time stamp when packet leave.
 

Normally the M4250 needs a local NTP server to calibrate the internal clock for more accurate time stamp. Install a ref clock module to calibrate the internal clock of M4250 surely helps offline operations.
 

@The Computer Audiophile in my recent Intel E810 project I found the M4250 still needs to change some switch settings before selecting AV template. For example the switch’s DSCP value 34 and 46 default priority were the same. Must assigned it correctly otherwise the PTP message and the audio stream would be treated equal. Usually we use DSCP 34 for audio / 46 for PTP by AES67 media profile standard. But some times I prefer using Ravenna standard 46 for audio / 48 for PTP.

 

1. manually select trust mode to DSCP

 

2. set the priority mapping correctly 

 

3. assign the proper DSCP priority

 

If I may offer a tweak to your DSCP Queue Mapping above, Netgear uses queue 7 for its own switch management routines so if you run clock signals (PTP) in queue 7 the CPU of the switch will be racing near 100% and you will notice that it takes a long pause to let you in to manage the switch. Just drop those settings marked with red outline by one so DSCP 56 in queue 6, DSCP 48 in queue 6, DSCP 46 in queue 5 and the audio transmission of AES67 in DSCP 34 should go to queue 4. You will not notice any change to the audio (well I didn't) and your switch is MUCH happier and able to do its job with greater ease.

 

Regards

GG

 

Edit: Dante users, the same applies but for some reason Audinate recommends giving a priority to DSCP 8 one lower than DSCP 34. So in El Guapo's post DSCP 8 would go to queue 4 or in my tweak, queue 3.

 

Ciao.

[GryphonGuy]

Hi Adrian,

 

Your marketing information states:

 

"2. The device should be powered externally with audiophile grade LPS"

 

Do you know of any currently available audiophile grade LPS that can output 5 amps at 54 volts?

 

If not, do you have plans to build one or have one built?

 

Regards

GG

[AfterDark.]

2 hours ago, GryphonGuy said:

Hi Adrian,

 

Your marketing information states:

 

"2. The device should be powered externally with audiophile grade LPS"

 

Do you know of any currently available audiophile grade LPS that can output 5 amps at 54 volts?

 

If not, do you have plans to build one or have one built?

 

Regards

GG

 

Hi! GryphonGuy,

 

Thanks for your information and questions.

 

There may be a possible solution to solver the high power requirement on this switch. We may disable the PoE hardware inside the M4250, so that the switch can operated with normal 12V -24DC. 

 

The Giesemann Clock Sync Module (GCSM) will be required to operated with LPS at 12V or 5V. 

 

Thanks again for your sharing on the Dscp/ DoS with repect to PTP setting. 

 

Have a nice day.

 

Best Regards,

Adrian

AfterDark.

 

 

[Mantheunknown]

5 hours ago, GryphonGuy said:

 

Do you know of any currently available audiophile grade LPS that can output 5 amps at 54 volts?

 

 

Hi

 

I do not know if these qualify as 'audiophile' grade

 

https://www.acopian.com/store/9-(7).aspx?min=36&max=70

 

I believe they can also be customized. Thx.

 

Cheers

[mumford]

Just wondering if you guys have considered other M4250 switches?

 

For example, this one has no POE and 2.5G ports

 

https://www.bhphotovideo.com/c/product/1663784-REG/netgear_msm4214x_100nas_m4250_12m2xf_av_switch.html

[AfterDark.]

Hi! Mumford,

 

This version is good choice too. We can bypass the switch power supply inside the chassis and use 12V DC for external LPS. The 2.5G and 1G SFP ports is controlled by latest Boardcom CPU with fanless design. 

 

Thanks and have a nice day.

 

Best Regards,

Adrian

AfterDark.