[somestranger26]

Apples and oranges. The Ref10 and SRS PERF 10 are Rubidum clocks, the Cybershaft is OXCO. Just a 10Mhz OXCO. Relock the OXCO Antelope with another OXCO?

Where do you see that Ref 10 is rubidium? I cannot find anything even hinting at that. In the info sheet for the Ref 10 they even criticize the use of rubidium ("atomic") clocks as unsuitable for digital audio.
 
Quote:

http://www.mutec-net.com/downloads/Ref10_InfoSheet_2014_E.pdf
 
Our researches have shown that so-called »atomic clocks« perform their high clock stability in a time domain not suitable for digital audio.

 
How do you reconcile your thoughts that Rb > OCXO when the one sample that we have of someone using both (see my previous post) shows that they preferred the OCXO for 90% of their music?

 

[jabbr]

Apples and oranges. The Ref10 and SRS PERF 10 are Rubidum clocks, the Cybershaft is OXCO. Just a 10Mhz OXCO. Relock the OXCO Antelope with another OXCO?

Where do you see that Ref 10 is rubidium? I cannot find anything even hinting at that. In the info sheet for the Ref 10 they even criticize the use of rubidium ("atomic") clocks as unsuitable for digital audio.

.
http://www.mutec-net.com/downloads/Ref10_InfoSheet_2014_E.pdf
 
Our researches have shown that so-called »atomic clocks« perform their high clock stability in a time domain not suitable for digital audio.

How do you reconcile your thoughts that Rb > OCXO when the one sample that we have of someone using both (see my previous post) shows that they preferred the OCXO for 90% of their music?

I think the reference to "atomic" clocks is in the general meaning of clocks with long term stability, while saying nothing about short term stability. For digital audio the short term stability is what matters most.

But indeed I have also never seen reported what type of clock is being used inside the Mutec Ref10. My guess would be it is crystal based as that is where their expertise lies.

Cheers

 

[Tand2016]

Hi
 
First time poster here .
 
I am very interested in trying a Rednet 16 in my setup.
 
(which consists of Mac mini 2011 with Amarra iRC > Curious USB 0,8 > Regen with JS-2 PSU > Curious Regen Link > Berkely USB/Spdif converter > Shunyata Anaconca AES 1,5 m > Berkeley Ref Dac)
 
I got a very good offer on a Rednet 16 R (Redundant). It was pretty much same price as the 16 AES since the dealer had the 16 R on stock and the 16 AES had to be ordered from Focusrite.
 
After looking at the spesifications, I notice the 16 AES and the 16 R looks the same and the dealer confirmes I do not need to use both PS to use it. Is there any reason I should not go for the R?
 
Thanks in advance!
 
Tommy 

 

[rb2013]

I don't know if I would agree with this statement.
Phase noise is an indicator of oscilator short term stability and I would imagine this would be just as important for a 10MHz clock as it would be for a word clock.
The word clock is probably locked to the 10MHz signal by a PLL circuit as well. The word clock will then follow the fluctuations of a 10MHz clock signal in generating its word clock, how far it follows will be depending on the PLL circuit design parameters.

How do you view this, why would it for a 10 MHz signal not be important what its phase noise is? Why would it be decoupled?

Well you have to separate phase noise and frequency stability short term and long term.  The Rubidium clock only acts a reference point for the main clock to discipline to.  In other words it gives a ultimate frequency reference point to the main clock to make small adjustments as it's clock drifts.
 
I love that calibration feature on the LiveClock - so over time the drift of a TXCO or even a OXCO will be orders of magnitude greater then a Rubidium clock - the Cesium clocks are the best (and insanely expensive - that is what is being used now by the Bureau of Time Standards).
https://en.wikipedia.org/wiki/Atomic_clock

The master atomic clock ensemble at the​

U.S. Naval Observatory​

in​

Washington, D.C.​

, which provides the time standard for the U.S. Department of Defense.​

[1]​

The rack mounted units in the background are​

Symmetricom​

(formerly HP) 5071A caesium beam clocks. The black units in the foreground are​

Symmetricom​

(formerly Sigma-Tau) MHM-2010 hydrogen maser standards.​

 

 
I disagree with those who say that long term clock drift does not matter for audio.  It's not like the clock somehow  manages to magically re-calibrate itself on each turn on/off.  When a crystal oscillator drifts long term - it moves away from accuracy.  In other words, over time this longer term drift will move the clocks SR frequency away from the absolute std reference frequency - say 192.00000Khz - to something different - either plus or minus.  That ref rate will then have a short term movement or drift around that drifted ref frequency - compounding the problem.  Drift on top of drift.
 
The magic of digital audio reproduction is based at it's core on the recording, then playback centered on an agreed ref SR.  The more the recording clock and playback clocks differ the greater the inaccuracy of playback of the live event.  So that ref can be 44.100Khz, or 96Khz, or 192Khz, etc...
 
The Atomic clocks have orders of magnitude (1000's of times) less drift on both the short and long term ref frequency.
 
Same applies for a 10MHz ref clock - the device accepting this ref freq to discipline to - is designed to work with an exact 10.0000000Mhz freq rate - not more or less.  The internal clock process then uses this ref freq rate to discipline the internal clock to.
 
The ultimate audio SR is still derived from the internal clock of the device.
 
In any event the phase noise of the PERF10 is -130db at 10Hz and -155db at 10Khz.
 
OT - We are so fortunate in the audio community to have ever less expensive precision clocks available to us - curtiosity of the GPS program.  In order to get precise (to 3M) the clocks on the GPS satellites have to adjust the length of a second to account for Einsteinian General Relativity - that is the bending of Time/Space by the Earth's gravitational well and the speed of the satellites (about 8K/MPH) relative to the Earth's surface - taking into account the opposite effect of Einsteinian Special Relativity!
https://www.youtube.com/watch?v=5qlLW60wOjo (30 minute marker)

 

[Iving]

  Hi
 
First time poster here .
 
I am very interested in trying a Rednet 16 in my setup.
 
(which consists of Mac mini 2011 with Amarra iRC > Curious USB 0,8 > Regen with JS-2 PSU > Curious Regen Link > Berkely USB/Spdif converter > Shunyata Anaconca AES 1,5 m > Berkeley Ref Dac)
 
I got a very good offer on a Rednet 16 R (Redundant). It was pretty much same price as the 16 AES since the dealer had the 16 R on stock and the 16 AES had to be ordered from Focusrite.
 
After looking at the spesifications, I notice the 16 AES and the 16 R looks the same and the dealer confirmes I do not need to use both PS to use it. Is there any reason I should not go for the R?
 
Thanks in advance!
 
Tommy 

 
See this post:
http://www.head-fi.org/t/806827/audio-over-ip-rednet-3-16-review-aes67-sets-a-new-standard-for-computer-audio/1425#post_12785122
 
I don't think I have come across anyone owning or using an R (so that you could have first hand advice). I suppose that if you use only one PSU you would not provoke any additional electrical noise. If the price is advantageous to you, I'm not aware of any other significant issues - but I would read the respective specs carefully if I were in your shoes.

 

[Tand2016]

Thanks Iving!
 
I have sent a mail to Focusrite. As far as I can se the specs are the same.
 
Tommy

 

[rb2013]

  Where do you see that Ref 10 is rubidium? I cannot find anything even hinting at that. In the info sheet for the Ref 10 they even criticize the use of rubidium ("atomic") clocks as unsuitable for digital audio.
 
How do you reconcile your thoughts that Rb > OCXO when the one sample that we have of someone using both (see my previous post) shows that they preferred the OCXO for 90% of their music?

That is interesting - is the Ref 10 using a 1G XCO too?
 
The SRS PERF10 uses a special cross cut Rubidium crystal to achieve it's remarkable phase noise numbers in a atomic clock.  A very difficult achievement - so ultra, ultra precise and extremely stable (short and long term) clock stability WITH sota low phase noise.
 
The audio effects can be explained a possible cancellation occurrence - in other words say the clock on his DAC or DDC has long term drifted minus - the OXCO maybe be plus - the net effect closer to absolute ref SR. 
 
Or the audible effect of the SR drift may produce inaccuracies that he finds pleasing or compensate for other aspects of his system.  Funny he prefers the OXCO only 90% of the time - not 100%.  If it was the best, you would think he would always want to use it.  Audio Ref clock as 'tone control'?

 
So you have system peculiarities and personal preferences involved - all totally valid.  Hence the YMMV std.

 

[rb2013]

I think the reference to "atomic" clocks is in the general meaning of clocks with long term stability, while saying nothing about short term stability. For digital audio the short term stability is what matters most.

But indeed I have also never seen reported what type of clock is being used inside the Mutec Ref10. My guess would be it is crystal based as that is where their expertise lies.

Cheers

Well they both matter - if the long term drift of an oscillator is then the starting point the short term drift will be +/- from this new increasingly over time inaccurate ref point.
 
So here are some actual numbers:
 
Crystek CCHD-957:
Initial accuracy: Depends on temperature they quote a range of +/- 20ppm to 50ppm
Long term drift: <3ppm 1st year, <1ppm each yr there after
 
Antelope LiveClock OXCO:
Initial accuracy: +/- 0.02ppm
Long term drift: <1ppm each year
 
SRS PERF10:
Initial accuracy: +/- .05ppb
Long term drift:  <.5ppb 1st year, 5ppb after 20 years!
 
So here the PERF10 has amazing ST accuracy but the LiveClock actually has better long term drift numbers.
 
PS Edit the Long term drift of the PERF10 is .5ppb NOT 5ppm.  Sorry I got my scientific notation mixedup.  So the PERF10 is orders of magnitude better then the LiveClock OXCO.
 
The PERF10 is something like 20,000 time more precise then a CCHD 957 TXCO and 1000 times more precise then the LiveClock OXCO after one year.  Now compound that year after year...

 

[somestranger26]

 
That is interesting - is the Ref 10 using a 1G XCO too?
 
The SRS PERF10 uses a special cross cut Rubidium crystal to achieve it's remarkable phase noise numbers in a atomic clock.  A very difficult achievement - so ultra, ultra precise and extremely stable (short and long term) clock stability WITH sota low phase noise.
 
The audio effects can be explained a possible cancellation occurrence - in other words say the clock on his DAC or DDC has long term drifted minus - the OXCO maybe be plus - the net effect closer to absolute ref SR. 
 
Or the audible effect of the SR drift may produce inaccuracies that he finds pleasing or compensate for other aspects of his system.  Funny he prefers the OXCO only 90% of the time - not 100%.  If it was the best, you would think he would always want to use it.  Audio Ref clock as 'tone control'?

 
So you have system peculiarities and personal preferences involved - all totally valid.  Hence the YMMV std.

 
I don't think they have divulged any details as to what the Ref 10 is using, but there's no mention of "atomic" anywhere in its marketing material and companies scream from the rooftops if their product is "atomic". I am guessing it is OCXO based on the amazing phase noise numbers that are pretty much unmatched except for the PERF10. SRS says they cut that special Rb clock themselves and it still costs $3500, so I doubt Mutec could manage even better phase noise numbers in their $4000 package while using a Rb clock.
 
Yes, perhaps the PERF10 is the best clock since you get the best of both worlds in terms of short and long term stability, but the same $3500 would pay for my RN3, Mutec MC-3+ USB, future LiveClock, and part of this Cybershaft Premium OCXO. I doubt anyone is willing to spend so much on just a clock; that's more than most people spend on their DAC.

 

[rb2013]

   
I don't think they have divulged any details as to what the Ref 10 is using, but there's no mention of "atomic" anywhere in its marketing material and companies scream from the rooftops if their product is "atomic". I am guessing it is OCXO based on the amazing phase noise numbers that are pretty much unmatched except for the PERF10. SRS says they cut that special Rb clock themselves and it still costs $3500, so I doubt Mutec could manage even better phase noise numbers in their $4000 package while using a Rb clock.
 
Yes, perhaps the PERF10 is the best clock since you get the best of both worlds in terms of short and long term stability, but the same $3500 would pay for my RN3, Mutec MC-3+ USB, future LiveClock, and part of this Cybershaft Premium OCXO. I doubt anyone is willing to spend so much on just a clock; that's more than most people spend on their DAC.

You are right on - for me $3500 for a PERF10 is insane.  Maybe for a Hedge Fund Manager.
 
The Cybershaft Prem numbers are stellar - and really hard to believe.  Orders of magnitude better then the PERF10 in stability!
 
It would have been nice if FocusRite had put a 10M input on the REDNET's - so no need for the Antelope in between.

 

[jabbr]

 

I don't think they have divulged any details as to what the Ref 10 is using, but there's no mention of "atomic" anywhere in its marketing material and companies scream from the rooftops if their product is "atomic". I am guessing it is OCXO based on the amazing phase noise numbers that are pretty much unmatched except for the PERF10. SRS says they cut that special Rb clock themselves and it still costs $3500, so I doubt Mutec could manage even better phase noise numbers in their $4000 package while using a Rb clock.

Yes, perhaps the PERF10 is the best clock since you get the best of both worlds in terms of short and long term stability, but the same $3500 would pay for my RN3, Mutec MC-3+ USB, future LiveClock, and part of this Cybershaft Premium OCXO. I doubt anyone is willing to spend so much on just a clock; that's more than most people spend on their DAC.

You are right on - for me $3500 for a PERF10 is insane.  Maybe for a Hedge Fund Manager.

The Cybershaft Prem numbers are stellar - and really hard to believe.  Orders of magnitude better then the PERF10 in stability!

It would have been nice if FocusRite had put a 10M input on the REDNET's - so no need for the Antelope in between.

I still very much doubt that value of a 10MHz reference clock.
Grimm states eir CC1 master clock will not be bettered by adding a 10MHz reference clock and that many a studio clock based on a 10MHz reference clock will be bettered by adding a very good word clock.

I find the people at Grimm very open and honest about the added/non-added value different types of clocks including their own. And for me they make a strong cases why a very good word clock will not be bettered by an atomic clock that only offers a long term accuracy but not a short term stability perse. If you can find both in one device than, hurray, your lucky. But otherwise Imwould not invest in one if you've got a good word clock already.

Cheers

 

[rb2013]

I still very much doubt that value of a 10MHz reference clock.
Grimm states eir CC1 master clock will not be bettered by adding a 10MHz reference clock and that many a studio clock based on a 10MHz reference clock will be bettered by adding a very good word clock.

I find the people at Grimm very open and honest about the added/non-added value different types of clocks including their own. And for me they make a strong cases why a very good word clock will not be bettered by an atomic clock that only offers a long term accuracy but not a short term stability perse. If you can find both in one device than, hurray, your lucky. But otherwise Imwould not invest in one if you've got a good word clock already.

Cheers

Does Grimm give any hard numbers on their clocks?  Besides their opinions?
 
Not all Atomic clocks are the same of course - but I doubt even their short term stability and accuracy numbers are better then the PERF10. 
 
Not saying the Grimm is not a fantastic clock.

 

[jabbr]

 

I still very much doubt that value of a 10MHz reference clock.
Grimm states eir CC1 master clock will not be bettered by adding a 10MHz reference clock and that many a studio clock based on a 10MHz reference clock will be bettered by adding a very good word clock.

I find the people at Grimm very open and honest about the added/non-added value different types of clocks including their own. And for me they make a strong cases why a very good word clock will not be bettered by an atomic clock that only offers a long term accuracy but not a short term stability perse. If you can find both in one device than, hurray, your lucky. But otherwise Imwould not invest in one if you've got a good word clock already.

Cheers

Does Grimm give any hard numbers on their clocks?  Besides their opinions?
 
Not all Atomic clocks are the same of course - but I doubt even their short term stability and accuracy numbers are better then the PERF10. 
 
Not saying the Grimm is not a fantastic clock.

They give these jitter specifications in their manual:

 
and their jitter graph (blue trace is the CC1)

 
 
 
and the phase noise from their clock circuit (red trace is their design):

 
They use a slow PLL design with a bandwidth of 0.1 Hz and a 0.1Hz cutt-off frequency.
on the actual oscilator crystal they only say: "The clock PLL is a hybrid analog / digital design, based on a discrete design ultra-low jitter crystal oscillator."

 

[rb2013]

  They give these jitter specifications in their manual:

 
and their jitter graph (blue trace is the CC1)

 
and the phase noise from their clock circuit:

Not phase noise numbers - clock stability and accuracy numbers - short and long term.  Antelope does.  Did not see any posted on their website.
 
The phase noise numbers are good - right in line with the totl clocks.

 

[jabbr]

 
They give these jitter specifications in their manual:



and their jitter graph (blue trace is the CC1)



and the phase noise from their clock circuit:

Not phase noise numbers - clock stability and accuracy numbers - short and long term.  Antelope does.  Did not see any posted on their website.

The phase noise numbers are good - right in line with the totl clocks.

No, they don't disclose anything on their components, just measurements of their circuits and functioning of the complete device.

Their marketing speak only goes thisfar:

Owing to a radically redesigned discrete crystal oscillator, clock stability betters that of even the best test equipment available.

It is also their PLL design with a 0.1 Hz bandwidth which makes me think a reference clock will not improve this master clock. This bandwidth of 0.1 Hz indicates that any difference between internal oscillator and external reference clock that is greater than 0.1 Hz will be discarded and not applied to correct the internal clock. This means that virtually everything will be discarded, and they can only do that and still have a good master clock when their internal crystal oscillator is extremely good and stable otherwise their master clock would not give good results.