Reality is Cruel : Cybershaft new Ultimate OCXO 10M Clocks Shootout OP20 vs OP17

SCAudiophile

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To get the best measuring clock and then introduce impedance mismatches has seemed counter-intuitive to me. Some are saying though that impedance mismatches matter far less though with sine wave than with square wave. Which type of clock signal yielded the side effects you folks heard?
Both; varying degrees of impact.

People tend to focus on square versus sine wave, using that to argue the point, and yes, I do get the difference certainly.

It "may" matter less with sine wave than square (stress this word as those who have said that had a long way to go to prove it so I categorize it as just opinion and something that is possible but not proven), however, that is not to say it does not matter at all.

I've always wondered though why this is one area of audio where some would advocate ignoring the fact that the manufacturer
had thought to pick a spec to follow, mark it, include it in the manual, etc..

I don't know all the answers, far from it; I do tend to practice "RTFM" figuring if the vendor followed a spec, I probably should too.
 

kennyb123

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Nov 30, 2012
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I've always wondered though why this is one area of audio where some would advocate ignoring the fact that the manufacturer
had thought to pick a spec to follow, mark it, include it in the manual, etc..
In a hobby where we repeatedly see that “everything matters”, it is a little surprising that some would ignore this. But maybe some have to because they face constraints. It surprised me that so few clocks support simultaneous 50 ohm and 75 ohm outputs.

As an aside, on Friday my REF10 returned from Mutec with the SE120 upgrade. The oscillator they selected actually measures -121 dBc at 1 Hz. The clock has barely settled in and yet it brought a tremendous upgrade.
 

SCAudiophile

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I agree with you kenny123 on that and are there are those that face constraints. Also, the truth is, going back a few years there were not many high quality 50-ohm cables. At that time we have Esoteric Mexcel 8N-A2000 (an excellent cable, owned 2) 50-ohm, Evolution Acoustics 50-ohm, and a very few others that all commanded steeper prices so those who would rationalize (as there were constraints) did so more frequently. Now, years later, there are many high-quality 50-ohm cables with proper 50-ohm terminations available from quite a few vendors including Habst, Shunyata and a quite a few others at various price points.

Some make the statements out of ignorance and others for various other reasons. There are still others, e.g. one dealer, who was quoted on his forum as saying "his actual testing verified that it didn't matter and it so happened that his favorite for-sale brand's 75-ohm cable was the best...." when in fact that brand did not make a 50-ohm cable. Seemed a bit convenient to me at the time,...perhaps I'm just cynical on this point <LOL>.

The differences are subtle in some cases and more pronounced in others however I do tend to believe based upon much trial, error and focused listening that it does make a difference.
 

QuadDiffuser

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From AXPONA 2022, the world-debut of Aurender’s MC20, with a MSRP of US$30k+ Personally, I’m confused about the merits and necessity of the expensive rubidium clock; its ultra-low long-term time drift is actually not as relevant as low phase noise offset (ideally, less than -120dBc at 1Hz), already available through calibrated and stable OCXOs in proven designs from Cybershaft and Mutec.
 

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CKKeung

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Hi John,
USD3xk is a big sum!

But I examined you photo carefully and noted that there were already two ocxo clock modules on the circuit board of this MC20 ext clock.
Why need the rubidium clock module?
IMG_20220427_173508.jpg

And I have never seen an ext clock with replaceable rubidium clock module.

I think Aurender must have some tricks up their sleeve!
:p
 
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QuadDiffuser

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Hi John,
USD3xk is a big sum!

But I examined you photo carefully and noted that there were already two ocxo clock modules on the circuit board of this MC20 ext clock.
Why need the rubidium clock module?
View attachment 92102

And I have never seen an ext clock with replaceable rubidium clock module.

I think Aurender must have some tricks up their sleeve!
:p
CK, the OCXOs are for 44.1k and 48.0k word clocks, whereas the rubidium oscillator is for the 10.0000MHz sine master clock. It’s the latter which I have reservations about.
 
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cykin

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Hi everyone,

I have just brought OP21A-D and found there is an Output level switch; LOW: 1.6 Vp-p HIGH: 3.0 Vp-p (4 system common switching 50 ohm). I am not quite sure of the function/difference of both selections.

I am going to connect it to N01XD. Please advise, thanks.
 

stevebythebay

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Oct 21, 2012
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Hi everyone,

I have just brought OP21A-D and found there is an Output level switch; LOW: 1.6 Vp-p HIGH: 3.0 Vp-p (4 system common switching 50 ohm). I am not quite sure of the function/difference of both selections.

I am going to connect it to N01XD. Please advise, thanks.
Seems that it would be advisable to contact Esoteric and Cybershaft (Kenji, who’s email is hasegawa@cybershaft.jp) to ascertain both the specific function of the setting and what is preferred based on whether using 50 or 75 ohm for the specific OP21 output. I’m assuming your dealer won’t have that level of knowledge, but I may be wrong.

Maybe others on this forum have more specific insights.
 
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SCAudiophile

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The N-01XD's only clock input is 50-ohm so make sure the dip switch (or switches if you bought a multiple output
model) are set to the 50-ohm setting. As an aside, if you bought a multi-output model of clock and will only connect
the N-01XD for now (or anything less than max number of outputs), I'd suggest using 50-ohm terminators on the
unused outputs. This is good hygiene in general for any clock, master clock, word clock, Cybershaft or not IMHO.

The switch you are referring to is for signal output strength as I understand it. For my own setups involving P03-U/D-03,
P-02/D-02 and now Grandioso P1/dual D1 stacks, "LOW" works perfectly and also yields a touch better sonics and
consistently shorter sync times. "HIGH" is reserved as I understand it for units that may expect or need higher signal
strength on their clock inputs to achieve sync.

As mentioned, in 3 generations of Esoteric gear, I've found LOW best and this has also tied with testing I've heard was done
by Cybershaft as well as many of their users.

I do not own the N-01XD however; I'd suggest writing Cybershaft at either the email given above ( hasegawa@cybershaft.jp ) or cybershaft777@yahoo.co.jp.

I'd also hazard a guess that like the multiple models I've owned the switch was set to LOW out of the box as that is
how it was tested and certified before shippings.

There is also a toggle switch for GROUND on later models (Chassis or ISOLATE); please consult the instruction guide and/or
write to them to seek advice for your setup as to which setting works best.
 

cykin

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Mar 23, 2022
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I have talked to Kenji and he is very helpful with my questions.

The input specification for the external 10MHz clock of the Esoteric N01XD you are using is 50ohm 1.0Vrms.

Therefore, the OP21A-D settings that meet the specifications are as follows.

Clock cable : BNC 50ohm Impedance ( The cable you have already ordered from us. )

Output level : LOW 1.6Vp-p

Output impedance : 50ohm

GND setting : isolate

Theoretically, the above settings are valid, but for audio equipment, the theory and practice may differ.

This is because the environment and circumstances in which the device is used vary from user to user.

Other than the above settings, you may get the situation you like.

Therefore, we recommend that you try all combinations of Output Level and GND settings.

There is no risk of damaging connected devices in all settings.
 
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zbub

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Jun 27, 2013
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New OP21A user report --

Happy Thanksgiving to everyone and it is also a good time to thank all the contributors to this thread that introduced Cybershaft to my radar. I’ve always wanted to try an external clock and I’ve never devoted so much time studying anything audio related during the past year. Clocks… seem like such a simple device…

Earlier this year I saw a used Cybershaft OP21E on a prominent audio-mark at a great price and I purchased it right away. I never got the unit. The seller stiff me and never completed the deal. Covid issues. Sure what else could it be? Eventually I got my money back and because of this unhappy experience, I just have to have an external clock…

Then with a combination of positive developments (favorable exchange rate, a trip to Japan etc) I was able to obtain an OP21A (4 outputs and external power supply) to connect to my CH D1.1/C1.1 front end. There are quite a few dCS owners reporting good/great results with Cybershaft on this thread but very few CH Precision. However, from other sites in Hong Kong and Taiwan I know there are more than a few people enjoying these clocks with CH and Esoteric.

When I made the purchase, I also bought 50-Ohm clock cables to get me started, as the current Transparent clock cable is too short. CH Precision only accepts either 75-Ohm or High-Z inputs, so I also got a pair of 50 to 75-Ohm adapters from Kenji-san. These extra adapters could affect the sound adversely, but for the time being I’d rather make sure the impedance is correctly matched before experimenting and investing more suitable 75-Ohm clock cables.
 

zbub

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Jun 27, 2013
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Both CH units locked on to the 10 MHz signal right away, and my first listening was 2 hours after powering up. Better focus, image size a little smaller than before but more defined. Overall sound was a little more laid back, and better musicality.

After 24 hours. Things got better. Much better.
With familiar recordings I heard more bloom and more hall. Details also got better, not only the instruments are more intelligible, but also other noises in the recordings as well.

Music sounded calmer (maybe that’s why my initial impression of laid back) but more vivid and alive (because of better focus and details). The focus plane moved a little back compared to no clock but the vocals didn’t “pop“ as much as before and image was smaller. At this time, besides the smaller image size and the fact that vocals didn’t pop as nicely as before, I’m hearing solid improvements.

Day 3 was still showing improvements. The vocal imaging issue had been eliminated. Things were snapping into sharp focus like well-focused photographs which was great. “Spanish Harlem” was simply mesmerizing. Great recordings benefitted greatly; lesser recordings didn’t transform into something great however.

Things got more interesting after one week. To my total surprise, bass got better and more dynamic along the way (good thing for sure, but how can a clock do that?) but instead of the sound continued to be a bit laid back, the sound got a lot more in your face forward (good or bad would be system dependent, in my case it was too much).

I had a bunch of isolation accessories on hand, and I used a set of magnetic footers underneath the granite board to get as much isolation as possible and that was quite useful. Using a better power cord also paid dividends.

I would say the overall improvements were even more than the .1 upgrades on CH which was a very pleasant surprise.
I purposely played some tracks that used to sound a bit congested before and right now I can follow the music a lot more easily. The interplay between musicians became much easier to follow and made more sense musically.
 

CKKeung

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Jun 17, 2011
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Hi zbub,
Big Congrats!

The ocxo module needs a week to stabilize when turned on.
However your OP21A is new so they have to undergo an even longer burn-in period.

The Cybershaft setup can be further optimized and here are some humble suggestions of mine :
1. The PSU and the OP21A should not be placed close together nor on the same platform. The transformer will adversely affect the main unit both because of emf and vibration.
2. Pls try audiophile footers for both chassis. The effect is easily audible. Their original feet are good but not outstanding.
3. Attaching audiophile groundboxes on them is definitely beneficial.
4. The ocxo module and circuit themselves generate noise into the powerline. Pls give the PSU a suitable power-conditioner.
4. The dc cable can also be upgraded. The effect is instantaneous.
5. Again, the original PSU is good and priced reasonably but the OP21A deserves a better PSU. Pls consider the Ediscreation Firebird LPS. I mentioned the resulting ear-opening improvement it gave to my frd Kahw's Cybershaft in my Firebird WFM thread.

Enjoy! :D
 
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Jpspock

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Congrats, I have the same but with one output. Normally, there a switch giving the possibility to choose between 50 or 75 ohm
 

Kris

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Mar 4, 2019
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Congrats, I have the same but with one output. Normally, there a switch giving the possibility to choose between 50 or 75 ohm
But the output connectors ( BNC) are also rated for 50 or 75 ohm.
So there will always be a trade of .
Some devices have a SEPARATE 50 ohm and 75 ohm exits to avoid connector mismach
 

zbub

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Jun 27, 2013
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Hi zbub,
Big Congrats!

The ocxo module needs a week to stabilize when turned on.
However your OP21A is new so they have to undergo an even longer burn-in period.

The Cybershaft setup can be further optimized and here are some humble suggestions of mine :
1. The PSU and the OP21A should not be placed close together nor on the same platform. The transformer will adversely affect the main unit both because of emf and vibration.
2. Pls try audiophile footers for both chassis. The effect is easily audible. Their original feet are good but not outstanding.
3. Attaching audiophile groundboxes on them is definitely beneficial.
4. The ocxo module and circuit themselves generate noise into the powerline. Pls give the PSU a suitable power-conditioner.
4. The dc cable can also be upgraded. The effect is instantaneous.
5. Again, the original PSU is good and priced reasonably but the OP21A deserves a better PSU. Pls consider the Ediscreation Firebird LPS. I mentioned the resulting ear-opening improvement it gave to my frd Kahw's Cybershaft in my Firebird WFM thread.

Enjoy! :D
Hi CK, thank you for all the suggestions. They were all sensible and made sense.
I just wanted to get things rolling due to my lack of experience with outboard clock and I know there are still lots of improvements that can be made.
 

zbub

Well-Known Member
Jun 27, 2013
119
48
333
Congrats, I have the same but with one output. Normally, there a switch giving the possibility to choose between 50 or 75 ohm
Hi yes the new OP21A can switch between 50 and 75 Ohms. It’s just that the clock cables I bought from Cybershaft were 50 Ohm cables but CH only had 75 Ohm input/output. I do have a Tranparent 75 Ohm clock cable but it’s too short.
Ultimately I will end up with new 75 Ohm clock cables so I can rid of the 50-75 ohm adapters.
 
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SCAudiophile

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Sep 11, 2010
1,156
435
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Greer South Carolina (USA)
New OP21A user report --

Happy Thanksgiving to everyone and it is also a good time to thank all the contributors to this thread that introduced Cybershaft to my radar. I’ve always wanted to try an external clock and I’ve never devoted so much time studying anything audio related during the past year. Clocks… seem like such a simple device…

Earlier this year I saw a used Cybershaft OP21E on a prominent audio-mark at a great price and I purchased it right away. I never got the unit. The seller stiff me and never completed the deal. Covid issues. Sure what else could it be? Eventually I got my money back and because of this unhappy experience, I just have to have an external clock…

Then with a combination of positive developments (favorable exchange rate, a trip to Japan etc) I was able to obtain an OP21A (4 outputs and external power supply) to connect to my CH D1.1/C1.1 front end. There are quite a few dCS owners reporting good/great results with Cybershaft on this thread but very few CH Precision. However, from other sites in Hong Kong and Taiwan I know there are more than a few people enjoying these clocks with CH and Esoteric.

When I made the purchase, I also bought 50-Ohm clock cables to get me started, as the current Transparent clock cable is too short. CH Precision only accepts either 75-Ohm or High-Z inputs, so I also got a pair of 50 to 75-Ohm adapters from Kenji-san. These extra adapters could affect the sound adversely, but for the time being I’d rather make sure the impedance is correctly matched before experimenting and investing more suitable 75-Ohm clock cables.
Congratulations zbub!
 

zbub

Well-Known Member
Jun 27, 2013
119
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333

Brand new top of the line Dela/Melco NAS which added a 10MHz clock input. Will be great with the new OP21 but price is $$$$$ and I just got a new Melco N1ZH this year : (
 
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