Master Clock for your EtherREGEN

[R1200CL]

1 minute ago, DarqueKnight said:

Now would be a good time to post a question to @AfterDark. on the AfterDark forum about the provenance of their OCXOs.

So would internal pictures as well as answering my questions about generic design, upgrade program etc. 

 

One guy even believe it’s the same clock everywhere. That can’t be the case. 

[R1200CL]

https://www.aliexpress.com/item/4001245799329.html
 

I will soon post about a group buy for a 50X50X10 mm tungsten block. (About 480 gram). 

 

It would be nice if anyone purchased the AfterDark clock would like to check if it fits that clock as well. 

[R1200CL]

Here is group buy to add a block on top of your OCXO as the picture above b

 

[R1200CL]

We definitely need fiber optic clock signals in the future. If Uptone, (Sonore), and AfterDark built this interface into products, we solved this isolation issues and need of several power supplies. 
 

@Superdad

Isn't such an interface quite straight forward, as long as the physical interface is chosen ?

What’s the drawback, if any ?

[R1200CL]

I’m starting to think standardize on 75 ohm for EtherRegen was a wrong decision. It was probably right at that time, but now that most clocks we use is 50 ohm, I suggest 50 ohm is the new standard. 

 

What do you guys think ?
 

 

[R1200CL]

16 hours ago, JohnSwenson said:

With the external clock you need to be sure that the impedances match all the way, if the ER has a 75 ohm input (this is the standard impedance), then you need a 75 ohm cable and a 75 ohm output from the clock box. If the clock box is 50 ohms, then you need a 50 ohm cable and the special order ER with the 50 ohm input.

John

One should think that a converter will do. A google search give so many to choose among. 
Should adopters 75>50 or 50>75 ohm in general be avoided ?

And spitters ?

 

When looking at various data sheets of OCXO clocks, they all seems to be 50 ohm. They often offered in two possible power options. Wouldn’t this indicate that it’s easier (and better) to produce a 50 ohm clock, as no resistor network is needed ? 

I assume you can have a direct line from the OCXO out to the connector. 
 

 

[R1200CL]

4 hours ago, fsmithjack said:

It was Queen Square Wave 75ohm special audiophilestyle edition.

That one is supplied with a nice Belden coax. Why you want to change ?

[R1200CL]

4 hours ago, fsmithjack said:

Have any of you guys tried a Grounding Cable like this for your EtherRegen?

 

I had nothing to ground it to so thought this might work well? Anyone try anything like this? 

 

What makes you think you need a grounding cable?

And why can’t you just use a simple wire ?

 

If you want to wast your money, I recommend this one. 
https://www.nordost.com/qrt/qline-groundwire.php

With the most expensive Furutech plug.  

[R1200CL]

59 minutes ago, fsmithjack said:

I don't want to stuff a bare wire into my outlet? Not sure what hole to stick it into...lol 

You connect a simple wire to the earth screw in a socket. Meaning the plug that you stick into the wall. You can purchase them almost anywhere. If you bought that cable with resistor, I suggest you cut and splice it, so you’re leaving the resistor out. 
 

Here is a search for you. 
https://audiophilestyle.com/search/?&q=Ground cable&author=JohnSwenson&search_and_or=and&sortby=relevancy

 

Also please read EtherRegen user guide carefully. It’s there for a reason. 

[R1200CL]

1 hour ago, fsmithjack said:

I am going to use my UP JS-2 to power multiple items and read it shares a ground internally so wanted to get a good external ground to make up for any that I may lose because I read that matters.

This is John’s own words if at any help. 
 

“Are you going to be powering anything else from the other output of the JS-2? By doing so you may wind up bypassing the isolation of the EtherREGEN. The grounds of the two outputs on the JS-2 are the same, thus if you power the EtherREGEN and something downstream (streamer, DAC, DDC etc) from the same JS-2 you are shorting the isolation (both sides having the same ground).”

 

I suggest you continue this discussion in another tread. 
Use the search function and you’re finding the specific post, and can quote and continue to ask about how to power everything. 
Making yourself some schematic may help you understand where you break isolation etc. 

 

Of cause clock cable belong here. 
And they can be a source to break isolation, which is more of a concern than length. 
 

https://cdn.shopify.com/s/files/1/0660/6121/files/EtherREGEN_User_Guide.pdf?90

[R1200CL]

24 minutes ago, GryphonGuy said:

You are trying to corrupt an industry standard.

I totally disagree.

 

https://www.wilsonamplifiers.ca/blog/50-ohm-vs-75-ohm-which-is-best-for-you/

 

https://www.microwaves101.com/encyclopedias/why-fifty-ohms

 

Even Esoteric uses 50 ohm. 
http://www.area51musicfest.com/products/catalog/pdf/g01_en-p.pdf

 

[R1200CL]

7 minutes ago, GryphonGuy said:

The fact remains, and I clarify for the scope changers amongst us, that my "industry" implication was for the Professional Audio Industry, where AUDIO clocks have traditionally been used.

 

https://sound-au.com/articles/coax.htm
 

Are these clocks 10 MHz ?

 

The fact also remains is that most if not all OCXO data sheets for 10 MHz  stats 50 ohm. 

[R1200CL]

8 minutes ago, LowMidHigh said:

Mutec Ref10 is furnished with both. The balance is tilted towards 75ohm, which reflects the majority of slave devices out there, e.g, MC3+USB and the ER. 

My understanding is a master world clock uses a different frequency than 10 MHz. Just because studio has used 75 ohms, cause cables as cheap, shouldn’t be our reason to standardize on 75 ohm. 
 

Anyway, most people looking for a clock for the EtherRegen will look at the cheap Chinese one, or hopefully AfterDark clocks. His clocks is 50 ohm. He just changed one clock for those that has the 75 ohm EtherRegen. The SU-1 used 50 ohm input. 

 

So using Mutec as a reference isn’t relevant these days.  And do we even know if there’s a 50 ohm or 75 ohm inside. Not that it really matter. 
 

Another important discussion is if we should standardize on square vs sine. Or does it matter at all. 

[R1200CL]

7 hours ago, LowMidHigh said:

Sorry, but you should do more research. The MC3+USB data sheet explicitly states 75ohm for its clock input BNC. 

That’s not the my point. It can still be a 50 ohm clock inside. But this discussion has anyway no meaning. 
You need to know what specific clock is in use. Of cause any 50 ohm OCXO clock can be 75 ohm by resistor network. 

[R1200CL]

@AfterDark.

Your post, and it’s not the first time, has problems with showing pictures. Can you talk to Chris and have it fixed. 

[R1200CL]

My thinking is that more products will have external clock input.

I don’t have the full answer how to best incorporate several clocks into a system. Hopefully John’s upcoming clock paper will give some answers. 
 

How much the various products will benefit from a better clock I don’t know, but based on the experience with even the very reasonable priced $93 clock used on EtherRegen, it’s my expectations that a clock will squeeze out even better performance in the digital chain wherever it’s being applied. 

It is also highly likely AfterDark clocks is the standard from now, based on price and performance. 
 

All his clocks was 50 ohm. He made a 75 ohm special square wave for use with EtherRegen.

He also made a 3 output 75 ohm clock with internal power and isolated outputs. 
 

My AfterDark clock purchase is on hold. I know I will purchase one. I just don’t yet know what’s best for me.  So much need to be planned. 

 

I know I kan purchase individually clocks powered by LPS 1.2 and be quite certain I won’t create any unwanted loops by the coax cable.

 

Let’s say there is a new Rendu with external clock input.
Maybe an optical Module with external clock input. 
You like to use a SU-1 or a DI-20 upfront your DAC. (I have no choice, and must use a DCC). 

You may like a second EtherRegen in your chain. 
 

Then you probably would prefer the same impedance for your clock.

Now, forget about impedance for a while, as if you purchase a 50 ohm clock, you can always use an adapter to create 75 ohm. But at the moment you can’t go the other way. At least not with AfterDark and Cybershaft products.

And yet the discussion of the use of adapters hasn’t started. 

 

Here is the challenge:

How do I create a good clock network without braking any isolation in my (your) devices ? 
Anyone willing to make that schematic using 4 clock inputs ?

There are so many variables, that you for sure need to make a schematic.

Try and post some bulletproof setups 😀 

(What a support hell is coming, if new products have external clock interface). 

For me personally, I can’t use AfterDark triple 75 ohm version as both DCC under evaluation is 50 ohm. The designer of the DI-20 tells me sine or square doesn’t matter.

 

I don’t know how much, if any, if a isolation circuit and square wave conversion affect the phase noise. 
I don’t know if there is several technics to implement isolation, and if there is god or bad sides how isolation is done. When knowing how much John and Alex has put into isolation for their products, I really need some convincing words about designing isolated multiple clock outputs. As well as switching 50/75 outputs. And why not make the isolation on the receiver side ? It can’t be that easy or ?

This is also why I’m thinking, but I don’t know for sure yet, that a singel (50 ohm) clock with isolated power by LPS 1.2 and a splitter may be the best solution. 
 

AfterDark has already confirmed that the combination of a 50 ohm spitter and a 50 to 75 ohm converter will work very well. I should also avoid any isolation issues by using Uptone LPS 1.2. 
 

Also I’m asking myself if there is a limit to how good phase noise numbers I really need.

 

We are not there yet, and if so it’s probably at least 2 years ahead before, if ever, we can have optical clock signals. (John has posted about the challenge in this tread). 

 

I’m holding my clock purchase from AfterDark on hold until John’s clock paper is our, as well as we (I) need to understand how many of the new products from Uptone and Sonore has a clock input. And of cause if it’s a 50 ohm or not. 
 

My conclusion for now is that 50 ohm should be the standard in clock interfaces. 
Several items seems to support 50 ohm input. The OCXO’s itself seems to be 50 ohm. 
If you have a 50 ohm clock, you can always use it on a 75 ohm input by an adapter, but not the other way. 

The decision of standardize on 50 ohm will not affect those that own a 75 ohm clock today. 
Why: Cause if any upcoming products won’t match your only only possible 75 ohm clock output, I predict both Uptone and Sonore will allow for a custom made 75 version of their products. I also noticed most clocks has the 50 ohm option anyway. 

 

Here is some (most ?) common other clocks.
Mutec REF10 has six 75-Ohm outputs and two 50-Ohm outputs. Cybershaft clocks are selectable. So really not an issue for those owners as well. Antelope is 75-Ohm  

 

Standardize on 50 ohm will make us choose more variants og AfterDarks clocks. And even the cheap AliExpress ones.

If AfterDark is to modifies his products any more, it may be from sine to square. But what can’t this be done at the receiver side. I have asked AfterDark how he measure a square wave clock, but haven’t got an answer. If I’m getting a sine clock, the supplied measurements for that clock is taken from the BNC connector. How important is it to have a square wave clock ? Can a conversion affect phase noise if not done properly ?

Anyone purchasing an EtherRegen from now is highly likely to benefit from a 50 ohm version. Unless you know you’re in for the special custom made AfterDark clock. 
 

 

 

 

[R1200CL]

12 hours ago, Roasty said:

 

Am I shorting anything or screwing up isolation with this setup? 

 

One AfterDark clock to ER and a second AfterDark clock to an sotm streamer. 

 

Keces P8 lps supplying 2 AfterDark clocks. Is that OK? Or should it be separate power supplies to each clock? 

Hi @Roasty

Your question needs a proper answer as you have posted a sketch. A sketch should be a requirement in my opinion from now on. 
 

I must say I’m not 100% sure, but I think you’re braking isolation by this setup. 
 

I haven’t studied previous similar questions and answer from John and Alex before, but maybe same PS to the EtherRegen and one clock will keep the EtherRegen still functioning as intended. (If going from A to B only). If that can be said as a general rule, it may be helpful to many. 
 

Also I think your sketch is missing how you’re powering the SMS-200. But I assume it’s a separate PS of cause b

Drawing the sketch like turning the ER 180 degrees helps. And showing power is applied on A side. Good that you use different colors. 
 

You can split power from the Farad if it’s more convenient. Ghent supplies split DC cables. 
 

Another interesting twist here is how about only using one clock and a spitter. Yes that will also break the isolation, but if your single clock was powered by an Uptone LPS 1.2. Wouldn’t that preserve isolation ?

 

 

 

[R1200CL]

57 minutes ago, Roasty said:

For the ER, does the clock input reside on the A side or B side? 

It’s my understanding both power and clock is A side. 
 

[R1200CL]

@Roasty

 

I guess this is correct ?
 

[R1200CL]

36 minutes ago, GryphonGuy said:

 

There can be another valid viewpoint. Perhaps its your configuration as I can see all photos from everyone AOK.

 

Regards

GG

Very strange. 
 

 

[R1200CL]

I’m testing various apps for iOS to make sketches on my iPad.
 

I just draw this one. I’m posting the sketch as an input to understand or plan a digital chain where clocks will be a part of it. I would assume a DCC isn’t the most common item, as most people seems to have USB DAC’s these days. Several have still found a DCC can make a DAC sound better. 
 

I’m not sure if it’s possible to make some general rules how to avoid braking isolation. What I state below is just my personal assumption. It may contain several errors. 
 

There is an isolation between A and B side. (As well as B to A). 
Same LPS to power two or more units may create loops. 
The use of LPS 1.2 (or the early LPS-1) will create isolation.

I assume some endpoints (The Rendu’s) has isolated USB out ?

The use of separate power will help, but still an ethernet cable or clock cable can create loops. 
It should be possible to power a clock with an LPS-1.2 and use a spitter to clock two items, if one of them is powered by a LPS 1.2

Grounding of EtherRegen is left out. As user guide says it’s normally not needed. 

 

I have left out clocks with isolated outputs for now. (It may seem as a optimal solution, but I don’t know).  
I have on purpose not said what’s between DCC and DAC. It shouldn’t matter. 

I can try to draw some more (generic) diagrams upon request in order to make examples so hopefully we getting some good guidance of what should work.

 

 

 

 

[R1200CL]

45 minutes ago, MasterWarzombie said:

What does DCC please mean?

A very good question. I was trying to avoid USB to SPDIF converter. As it can also output I2S. 
A DCC could probably be anything that converts or recloock a digital signal ?
D=Digital C=Converter

So I’m missing on one C 😀

 

Here is a manufacturer using DCC

https://www.denafrips.com/ddc

[R1200CL]

3 hours ago, James Stephens said:

 

Adrian will so be so excited you are going to buy of his 3 clocks.

 

.....or I (and some of you as well hopefully), could convince him to make a DC powered 3 isolated selectable 50/75 ohm square wave output version. With sine tapping as well. 
 

That should please most of us, for some time. 
 

The challenge is what grade(s) to go for.

I like Emperor DOUBLE CROWN, and hope that level of phase noise is more than sufficient. 
A target not to get to much above $999 maybe ?

 

[R1200CL]

Here is some of the apps tested to draw on my iPad 

 

The one with red circle I preferred. 
 

 

 

Under is an example done with that app. 
 

 

 

It’s not totally strait forward everything, but I good good support from the designer. And then everything was just so easy and fast to do. And fun. 

 

The above sketch is equal to what @Roasty like an answer to. Is the configuration braking any isolation or possibly create unwanted loops. 

[R1200CL]

4 hours ago, GMG said:

After this experience I think I will go to the GAIA (or Hermes), before upgrading the clock (if at all)

Do you know the phase noise numbers from Denafrips ?

 

Reason i out ruled Denafrips DDC, was lack of external input clock. SU-2 is what I’m planning for.

But maybe you own a Denafrips Terminator DAC already, if not it doesn’t make any sense I would say. 
The clock inputs of those DCC is not 10 MHz.