Master Clock for your EtherREGEN

[jean-michel6]

On 12/28/2020 at 3:59 PM, GS6 said:

Having seen the big sonic boost provided by 1st the external clock, second the tungsten block, 3rd an isolation platform, and 4th making a 20cm clock cable from solid silver Oyaide 75ohm cable and solid silver Oyaide 75ohm BNC connectors

Have you compared your homemade Oyaide clock cable to any other cable ? 

[GS6]

4 hours ago, jean-michel6 said:

Have you compared your homemade Oyaide clock cable to any other cable ? 

Hi Jean-Michel,

I started with this Enoaudio cable. 

It uses 50cm of Mogami 2964 and Canare BCP-A3F connectors. 

 

It seemed totally fine to be honest, and I wouldn't have thought too much about the Oyaide cable unless I'd noticed the spare 30cm piece of cut-off I had in my parts box (leftover from making an RCA-RCA Coax).

 

The Oyaide cable is only available in 100cm lengths (I believe), and is around £100 per 1m. I wouldn't have went out and bought 100cm just to make the clock cable, so it was fortuitous that I had it spare. 

I then managed to find the Oyaide SLSB BNC connectors discounted to £90 (normally £110-£140 depending on supplier) so thought it was worth exploring. 

 

The pro-rata costs of the cable plus the connectors bring the finished clock cable in at around £120, which is more than I paid for the master clock itself, and is 4x more expensive than the Enoaudio cable I purchased, and more than some of the other cables recommended in this thread. 

 

Is the Oyaide DIY cable 4x better than the Enoaudio cable. No, not in such absolute terms. 

There is a clearly audible improvement in sound quality, but it is not '4x' better. 

 

Was the £90 for the connectors worth it given I already had the spare length of cable around?

To me, yes. I think the enjoyment of experimenting, of assembling/modifying another piece of my system myself, and the sonic improvements all add up to being worth the extra £90 vs the ready bought cable. 

 

There is a small improvement in dynamics, the background is darker, and everything just seems a little more 'in it's place' with the home made cable. 

 

(The improvement could even be because the cable is shorter, or better screened, it may not be anything to do with the better silver core and silver connectors; I just know it's better to my ears. )

 

As mentioned, I'm waiting on my linear power supply arriving, so will try both cables again once that has had some time to settle; the lps may make differences in the clock cables more easily identifiable. 

 

G

[jean-michel6]

Hi G 

 

Thank’s for your detailed answer . I may try as you did since I would like also to try a nice spdif 75 ohms cable from my server to my dac . 
I will be also able to build a clock cable as you did .

My self i already have the canare and the Apogee wide eye .

 

What do you think of the tungstène bloc , did you use the 25mm ? In my opinion it is just a weight which dampens vibration . Crystal oscillator do not like vibrations .

The power supply is always very important for the digital equipment , myself I am using a Sean jacobs psu to power this clock but I did not make any comparison with others psu .

 

[manueljenkin]

Happy new year to all!

 

Came across this recently: https://en.antelopeaudio.com/products/10mx/ (rubidium transition based clock).

 

Not sure if it can trickle down to consumer levels but interesting nevertheless.

[Superdad]

9 minutes ago, manueljenkin said:

Happy new year to all!

To you too! 

 

9 minutes ago, manueljenkin said:

Came across this recently: https://en.antelopeaudio.com/products/10mx/ (rubidium transition based clock).

 

Not sure if it can trickle down to consumer levels but interesting nevertheless.

Might be okay for the prosound studio with all those features, but miserable performance for audiophile applications. Especially for $6,500...

From their spec page, the phase-noise is:

1Hz ≤-70 dBc/Hz
10Hz ≤-87 dBc/Hz

 

The $100 reclaimed cell tower OCXO clock that this thread stated with is about -125dBc/Hz at 10Hz offset for 10MHz carrier. And the 25MHz Crystek CCHD-575 built into the EtherREGEN is (if adjusted by 6dB/octave to what it would be as a 10MHz clock) about -119dBc/Hz at 10Hz offset.

[JohnSwenson]

1 hour ago, manueljenkin said:

Happy new year to all!

 

Came across this recently: https://en.antelopeaudio.com/products/10mx/ (rubidium transition based clock).

 

Not sure if it can trickle down to consumer levels but interesting nevertheless.

I've said this many times before but I'll say it again. What matters for digital audio is the phase noise, the absolute accuracy, and the aging (drift over time) and temperature coefficient do not matter. These are all so good that they will not even come into the picture for digital audio.

 

The lowest phase noise is produced by the best crystal oscillators, period. All these other types of clocks (mostly "atomic clocks" such as rubidium, cesium, hydrogen maser, cesium fountain) all have lousy phase noise, but great long term stability (fractions of a part per billion), which is completely meaningless for digital audio. The time it will take to get a one second error is greater than the age of the universe, but that is meaningless for digital audio!

 

Even when you want to very accurately measure time a rubidium oscillator is not a good choice any more. For example I have a GSPDO, GPS Disciplined Oscillator, which cost a whopping $200 and has about 1000 times better frequency stability than even very good rubidiums.  A GPSDO takes a good OCXO (which has quite low phase noise, very good short term stability) and SLOWLY tweaks it with the timing results coming out of a GPS timing receiver. GPS works by knowing the time very accurately and comparing that with signals from satellites (which come from very good atomic clocks IN the satellites) which have extremely accurately known orbits, from which your location can be accurately computed. But it also works the other way, if you know your location extremely well you can compute the time extremely well. GPS timing receivers assume they are stationary and over a period of many hours compute their location extremely well, thus they know the time extremely well. Thus such a device provides you time accuracy which is actually better than what is in the satellites, because it uses the signals from many satellites, which gives you an average which is better than any of them alone. This is weird but an $80 GPS timing receiver gives you more accurate time than a $100,000 atomic clock!

 

So never EVER, think about getting a rubidium clock, there is no reason for them no matter what you are trying to do.

 

But that doesn't mean you need a GPSDO for digital audio. That tweaking of the OCXO that happens in the GPSDO increases the phase noise of the OCXO, so for digital audio you get better results with just the OCXO.

 

John S.

[RickyV]

7 minutes ago, JohnSwenson said:

The time it will take to get a one second error is greater than the age of the universe,

😁😁

[manueljenkin]

Thank you. Sorry for the unintended diversion. One question though, is why do atomic clocks have worse phase noise?

 

[Confused]

8 hours ago, Superdad said:

To you too! 

 

Might be okay for the prosound studio with all those features, but miserable performance for audiophile applications. Especially for $6,500...

From their spec page, the phase-noise is:

1Hz ≤-70 dBc/Hz
10Hz ≤-87 dBc/Hz

 

The $100 reclaimed cell tower OCXO clock that this thread stated with is about -125dBc/Hz at 10Hz offset for 10MHz carrier. And the 25MHz Crystek CCHD-575 built into the EtherREGEN is (if adjusted by 6dB/octave to what it would be as a 10MHz clock) about -119dBc/Hz at 10Hz offset.

Or for another comparison, the Mutec REF 10 has phase noise measurements as follows:

 

1 Hz ≤ -116 dBc/Hz (the new SE120 improves this to -120 dBc/Hz)

10 Hz ≤ -145 dBc/Hz

 

OK - The reclaimed cell tower OCXO's are the value for money offering here, but the Mutec REF 10 is cheaper than the Antelope 10MX, and offers higher performance whare it matters.

[Pro Jules]

I auditioned one on my system and it was very good sounding. 

 

Some specs. 

 

measurement diagram attached. The most important phase noise value at 1 Hz distance from the carrier frequency (10 MHz) is even slightly better as -121 dBc which results in a jitter value of 14.25fs. 

 

 

 

MUTEC OCXO SE-120,621550,Jules Standen.pdf

[Pro Jules]

Measurement PDF attached. 

[JohnSwenson]

16 hours ago, manueljenkin said:

Thank you. Sorry for the unintended diversion. One question though, is why do atomic clocks have worse phase noise?

 

Aha, THAT as they say is a good question!

 

The understand that you have to understand how they both work. The crystal oscillator is easy, quartz actually changes shape when an electric field is applied. It has a sharp "resonance" frequency where the expansion and contraction works extremely well. Same thing as a swing, if you "pump" a little energy into it at the right frequency you get large excursions. If you pump it at some other frequency not much happens. Same thing with the crystal. The oscillator circuit is just a high gain amplifier fed back into itself, which naturally oscillates. Then throw the crystal into the loop and it oscillates at that one frequency. 

 

This gives very low phase noise, but the exact frequency can move around with temperature, electrical parameters of the circuit etc. You don't get something that is always exactly at the precise frequency no matter what.

 

Atomic clocks are very different. They make use of "spectral lines" of certain elements. You are probably aware of optical spectral lines, say the green and blue lines of mercury (common in older street lights). These are caused by atoms which are pumped by electrical current running through a plasma made of the element in question, these cause the electrons in the atoms to go to a higher energy stage (An incorrect, but useful visualization are electrons in orbits around a nucleus, the reality is much more complex, but this is a useful quick and dirty visualization). They eventually loose that energy by emitting light of a specific frequency. When you pass that light through a prism you can see the "spectral lines" of those specific light emissions.

 

But you can't use those directly, the lines are actually not one frequency but many frequencies called "fine structure". The fine lines are much more precise but harder to determine the frequencies. It turns out the fine lines can even be sub-divided into hyperfine structure if you look REALLY carefully. The frequency of a fine line is determined by the electron distribution in an atom, so it still depends on interactions of one atom to the next so they vary somewhat. BUT the hyperfine lines are determined by the interactions of the nucleus with the electrons, and the nucleus is FAR more stable and less affected by what is around it, thus ideal for time measurement.

 

The energy difference between these lines is very small so the electromagnetic waves are in the microwave region. An atomic clock works by pumping a gas of the particular atoms so that they give off light, including the line of interest, then microwaves of the particular frequency are added to the chamber. When the microwaves are tuned to the exact frequency a little bit of it is absorbed by the hyperfine line producing a very small dip in the intensity of the microwaves. The atomic clock works by slowly moving the microwave frequency across the region of interest and slowly "narrowing in" on the frequency of the dip. That microwave frequency is then measured and THAT gives the timing of the "atomic clock".

 

I hope it is obvious that this process is very "fiddly". You are trying to make extremely sensitive measurements of very small things. Such measurements are always quite noisy, thus the phase noise is high. BUT when you average it out over months (or years!) The frequency is very precise.

 

It always fascinates me that engineers have been able to put this process into a small box that can be put in satellites!

 

Ok, way more than you ever wanted to know. But that is why atomic clocks by themselves have terrible phase noise.

 

John S.

[manueljenkin]

Thank you John. Bringing it back on topic, few more questions.

 

1 hour ago, JohnSwenson said:

The understand that you have to understand how they both work. The crystal oscillator is easy, quartz actualyl changes shape when an electric field is applied. It has a sharp "resonance" frequency where the expansion and contraction works extremely well. Same thing as a swing, if you "pump" a little energy into it at the right frequency you get large excursions.

Would this resonance frequency also depend on the pressure and temperature of air around it and the angular alignment of the crystal (parallel to gravitational force vs perpendicular to gravitational force, ie shear stress vs normal stress). We had piezoelectric effect in undergraduate course but I don't remember reading about the causation. Having a read at Wikipedia on the topic, it looks rigorous but very interesting.

 

1 hour ago, JohnSwenson said:

The oscillator circuit is just a high gain amplifier fed back into itself, which naturally oscillates. Then throw the crystal into the loop and it oscillates at that one frequency. 

Ignoring high precision circuits where things might be more complex, I assume a basic oscillator can make use of feedback network and amplifier that satisfies barkhausen criterion.

1 hour ago, JohnSwenson said:

Atomic clocks are very different. They make use of "spectral lines" of certain elements. You are probably aware of optical spectral lines, say the green and blue lines of mercury (common in older street lights). These are caused by atoms which are pumped by electrical current running through a plasma made of the element in question, these cause the electrons in the atoms to go to a higher energy stage (An incorrect, but useful visualization are electrons in orbits around a nucleus, the reality is much more complex, but this is a useful quick and dirty visualization). They eventually loose that energy by emitting light of a specific frequency. When you pass that light through a prism you can see the "spectral lines" of those specific light emissions.

 

But you can't use those directly, the lines are actually not one frequency but many frequencies called "fine structure". The fine lines are much more precise but harder to determine the frequencies. It turns out the fine lines can even be sub-divided into hyperfine structure if you look REALLY carefully. The frequency of a fine line is determined by the electron distribution in an atom, so it still depends on interactions of one atom to the next so they vary somewhat. BUT the hyperfine lines are determined by the interactions of the nucleus with the electrons, and the nucleus is FAR more stable and less affected by what is around it, thus ideal for time measurement.

 

The energy difference between these lines is very small so the electromagnetic waves are in the microwave region. An atomic clock works by pumping a gas of the particular atoms so that they give off light, including the line of interest, then microwaves of the particular frequency are added to the chamber. When the microwaves are tuned to the exact frequency a little bit of it is absorbed by the hyperfine line producing a very small dip in the intensity of the microwaves. The atomic clock works by slowly moving the microwave frequency across the region of interest and slowly "narrowing in" on the frequency of the dip. That microwave frequency is then measured and THAT gives the timing of the "atomic clock".

 

I hope it is obvious that this process is very "fiddly". You are trying to make extremely sensitive measurements of very small things. Such measurements are always quite noisy, thus the phase noise is high. BUT when you average it out over months (or years!) The frequency is very precise.

Thank you very much for the detailed explanation. I would require some more time to understand this completely, but a few doubts (clarifications) here too.

 

1. We are using the frequency of light in a particular way to get our clock? (Light is also an electromagnetic wave so it should interact with other electromagnetic waves).

 

2. Are these hyperfine levels related to the wave equations etc? In that case I believe both the temperature and crystal structure (formed after the long processes natural or artificial which could involve heating, pressure etc so the new stable structure may not completely go hand in hand with the general assumed Paulis exclusion principle), and impurities would cause changes to this hyperfine structure frequencies? (Like different structures of carbon having different thermal, optical and mechanical properties) But in any case, I guess for a well defined crystal lattice it'll be far more stable over time unlike oscillators which drift due to changes in mechanical, crystal and chemical structure. Edit: I think I got it now. The patterns do change from one produced variant to another and also at one point to another within the same device due to the effects mentioned above but the hyperfine "delta" between two levels remain almost constant (or is less varying as compared to the other effect since nucleus is very far away and the influences are similar). Is that correct?

 

3. We use some circuit to generare a microwave that has an energy that is equal to the energy difference between the two hyperfine states so the electron absorbs, moves to the higher orbit and then after a short time jumps back to the old orbit for stability emitting back this light (would this emitted light be in the same direction as incident light? Not necessarily right). And we have some form of feedback loop that changes the parameters of the circuit generating the em wave to be incident on the atoms. It should ideally try to maximize intensity of the absorbed wave (or minimize considering that the atom absorbs the light, but then where to we get the output? Do we take two outputs from the wave generation circuit, one going to the feedback loop that has this atomic interactions, and the other used as output?).

 

4. If the hyperfine levels are so close won't we have the possibility of our input frequency also exciting the other levels and making the circuit design harder?

[JohnSwenson]

33 minutes ago, manueljenkin said:

Thank you John. Bringing it back on topic, few more questions.

 

Would this resonance frequency also depend on the pressure and temperature of air around it and the angular alignment of the crystal (parallel to gravitational force vs perpendicular to gravitational force, ie shear stress vs normal stress). We had piezoelectric effect in undergraduate course but I don't remember reading about the causation. Having a read at Wikipedia on the topic, it looks rigorous but very interesting.

 

Ignoring high precision circuits where things might be more complex, I assume a basic oscillator can make use of feedback network and amplifier that satisfies barkhausen criterion.

Thank you very much for the detailed explanation. I would require some more time to understand this completely, but a few doubts (clarifications) here too.

 

1. We are using the frequency of light in a particular way to get our clock? (Light is also an electromagnetic wave so it should interact with other electromagnetic waves).

 

2. Are these hyperfine levels related to the wave equations etc? In that case I believe both the temperature and crystal structure (formed after the long processes natural or artificial which could involve heating, pressure etc so the new stable structure may not completely go hand in hand with the general assumed Paulis exclusion principle), and impurities would cause changes to this hyperfine structure frequencies? (Like different structures of carbon having different thermal, optical and mechanical properties) But in any case, I guess for a well defined crystal lattice it'll be far more stable over time unlike oscillators which drift due to changes in mechanical, crystal and chemical structure. Edit: I think I got it now. The patterns do change from one produced variant to another and also at one point to another within the same device due to the effects mentioned above but the hyperfine "delta" between two levels remain almost constant (or is less varying as compared to the other effect since nucleus is very far away and the influences are similar). Is that correct?

 

3. We use some circuit to generare a microwave that has an energy that is equal to the energy difference between the two hyperfine states so the electron absorbs, moves to the higher orbit and then after a short time jumps back to the old orbit for stability emitting back this light (would this emitted light be in the same direction as incident light? Not necessarily right). And we have some form of feedback loop that changes the parameters of the circuit generating the em wave to be incident on the atoms. It should ideally try to maximize intensity of the absorbed wave (or minimize considering that the atom absorbs the light, but then where to we get the output? Do we take two outputs from the wave generation circuit, one going to the feedback loop that has this atomic interactions, and the other used as output?).

 

4. If the hyperfine levels are so close won't we have the possibility of our input frequency also exciting the other levels and making the circuit design harder?

Wow, someone who gets this stuff! I'll make an attempt to answer this stuff. First off I forgot to mention magnetic fields. The whole process takes place in a strong magnetic field which tends to align spins making these lines easier to detect.

 

#1, this is a gas at low pressure, it doesn't have to be ultra high purity, but that does help. Visual light is used to pump the gas to the particular line in question. So the gas is glowing at that color (line) that contains the hyperfine line in question.

 

#2, YES! This is all about the wave equations for the atoms. But not just the electron cloud but of the nucleus as well. Your second part is correct. The fine lines ARE changed by interactions from one atom to the nearby atoms in the gas. But the hyperfine lines are nucleus to its own electrons which are much closer than the electrons in other atoms due to the low pressure of the gas. That is actually one of design parameters, lower gas pressure give less interaction with other atoms, but fewer atoms to look at! The energy difference between hyperfine lines stays constant, even though temperature, pressure etc are changing the fine structure.

 

#3, Good question, I'm not quite sure. It always seems that when you are using a microwave field to tune for such lines, when you are in tune the field gets lower (atoms absorb the microwaves). I'm not sure what happens with the re-emitted em waves.

 

 There are two ways to do the feedback, one has a separate coil of wire going to an amplifier to detect the amplitude of the field for the feedback loop, the other just measures the electrical signal going into the chamber. The electrical signal going in is always what is used to measure the frequency.

 

#4, you bet! That is always one of the big issues with the designs. Really good deigns these days use hydrogen masers for that purpose! (they cost $250,000 and are the size of a refrigerator).

 

The REALLY top of the line ones these days are called "fountains" they let the atoms fall in free space so the interactions between atoms is extremely small.

 

I think we better stop this now, Alex is probably going to get annoyed with this digression from EtherREGEN stuff.

 

 

John S.

[manueljenkin]

56 minutes ago, JohnSwenson said:

Wow, someone who gets this stuff! I'll make an attempt to answer this stuff. First off I forgot to mention magnetic fields. The whole process takes place in a strong magnetic field which tends to align spins making these lines easier to detect.

 

#1, this is a gas at low pressure, it doesn't have to be ultra high purity, but that does help. Visual light is used to pump the gas to the particular line in question. So the gas is glowing at that color (line) that contains the hyperfine line in question.

 

#2, YES! This is all about the wave equations for the atoms. But not just the electron cloud but of the nucleus as well. Your second part is correct. The fine lines ARE changed by interactions from one atom to the nearby atoms in the gas. But the hyperfine lines are nucleus to its own electrons which are much closer than the electrons in other atoms due to the low pressure of the gas. That is actually one of design parameters, lower gas pressure give less interaction with other atoms, but fewer atoms to look at! The energy difference between hyperfine lines stays constant, even though temperature, pressure etc are changing the fine structure.

 

#3, Good question, I'm not quite sure. It always seems that when you are using a microwave field to tune for such lines, when you are in tune the field gets lower (atoms absorb the microwaves). I'm not sure what happens with the re-emitted em waves.

 

 There are two ways to do the feedback, one has a separate coil of wire going to an amplifier to detect the amplitude of the field for the feedback loop, the other just measures the electrical signal going into the chamber. The electrical signal going in is always what is used to measure the frequency.

 

#4, you bet! That is always one of the big issues with the designs. Really good deigns these days use hydrogen masers for that purpose! (they cost $250,000 and are the size of a refrigerator).

 

The REALLY top of the line ones these days are called "fountains" they let the atoms fall in free space so the interactions between atoms is extremely small.

 

I think we better stop this now, Alex is probably going to get annoyed with this digression from EtherREGEN stuff.

 

 

John S.

Thank you John. I will stop with the questions here too. I had created a thread in objective fi just for theoretical knowledge sharing. We could add this (and if possible, continue) there after few other tasks are done.

 

 

[MartinT]

If I had known what I was starting with this thread back in May...  😄

[jamesg11]

Yes, back to mundane on-topic matters ... I’m still waiting on my clock, ordered mid-Nov ...

[ambre]

On 1/2/2021 at 3:50 AM, JohnSwenson said:

Wow, someone who gets this stuff! I'll make an attempt to answer this stuff. First off I forgot to mention magnetic fields. The whole process takes place in a strong magnetic field which tends to align spins making these lines easier to detect.

 

#1, this is a gas at low pressure, it doesn't have to be ultra high purity, but that does help. Visual light is used to pump the gas to the particular line in question. So the gas is glowing at that color (line) that contains the hyperfine line in question.

 

#2, YES! This is all about the wave equations for the atoms. But not just the electron cloud but of the nucleus as well. Your second part is correct. The fine lines ARE changed by interactions from one atom to the nearby atoms in the gas. But the hyperfine lines are nucleus to its own electrons which are much closer than the electrons in other atoms due to the low pressure of the gas. That is actually one of design parameters, lower gas pressure give less interaction with other atoms, but fewer atoms to look at! The energy difference between hyperfine lines stays constant, even though temperature, pressure etc are changing the fine structure.

 

#3, Good question, I'm not quite sure. It always seems that when you are using a microwave field to tune for such lines, when you are in tune the field gets lower (atoms absorb the microwaves). I'm not sure what happens with the re-emitted em waves.

 

 There are two ways to do the feedback, one has a separate coil of wire going to an amplifier to detect the amplitude of the field for the feedback loop, the other just measures the electrical signal going into the chamber. The electrical signal going in is always what is used to measure the frequency.

 

#4, you bet! That is always one of the big issues with the designs. Really good deigns these days use hydrogen masers for that purpose! (they cost $250,000 and are the size of a refrigerator).

 

The REALLY top of the line ones these days are called "fountains" they let the atoms fall in free space so the interactions between atoms is extremely small.

 

I think we better stop this now, Alex is probably going to get annoyed with this digression from EtherREGEN stuff.

 

 

John S.

 

On 1/2/2021 at 1:51 AM, JohnSwenson said:

Aha, THAT as they say is a good question!

 

The understand that you have to understand how they both work. The crystal oscillator is easy, quartz actually changes shape when an electric field is applied. It has a sharp "resonance" frequency where the expansion and contraction works extremely well. Same hyperfine structure if you look REALLY carefully. The frequency of a fine line is determined by the electron distribution in an atom, so it still depends on interactions 

 

John S.

Hallo John and others,

 

I just found a masterclock of Teac. Can you tell me if this masterclock as used as add-on for the Teac DAC UD 505 can also be used for my EtherRegen?

Ps. Price in Europe approx, € 1300,00 that much cheaper than the Mutec etc.

I have copied a summary of the Specs:

The CG-10M is a master clock generator that delivers an extremely accurate clock signal to allow Digital-to-analogueue converters (DACs) to perform at their ultimate best.

It is a well-known fact among audiophiles that the clock signal is the foundation for all digital signal processing. For example, digital signals, such as PCM, are divided extremely finely into tens of thousands of parts per second along the time axis. If that fundamental time axis fluctuates during the process of D/A conversion it is much more difficult to render an analogue audio waveform that is identical to the original. This is all the more true with DSD audio signals that function at MHz speeds in the time axis. For this reason, having as accurate a clock signal as possible is very important for the re-creation of digital audio signals, particularly HiRes files that use ultra high sampling-rates, such as DSD 22.5MHz or PCM 768kHz.

At the heart of the master clock generator is a crystal oscillator, encased in in a temperature-  controlled box, the "oven", to maintain the best and stable performance under an ideal temperature condition for crystal oscillation. This oven-controlled crystal oscillator (OCXO, for short) generates an extremely accurate 10MHz clock signal which is within ±3 ppb of frequency temperature characteristics and within ±0.1 ppm of frequency precision.

The elegant analogue gauge on the front panel gives a visual indication of the status of the internal crystal oscillator at all times..

The CG-10M is a master clock generator that brings out the best performance from USB DACs, network players, CD players and any other kind of device that supports a 10MHz clock input.

Main Features

 

High-precision "TEAC Reference OCXO" – an ‘oven-controlled’ crystal oscillator

±3 ppb frequency temperature characteristics, ±0.1 ppm frequency precision

4 x 10MHz clock output connectors (gold-plated BNCs)

Completely independent and isolated circuit

High capacity toroidal-core power transformer

OVEN STATUS gauge with dimmable backlight, for monitoring oscillation stability 

3-positioned Patented Pin-Point feet to minimise vibrations

Full-metal body to eliminate incoming electromagnetic noise

 

 

A class-leading ultra high-precision clock

Thanks to the TEAC Reference OCXO, the CG-10M delivers an ultra high-precision 10MHz clock signal – within ±3 ppb of frequency temperature characteristics and within ±0.1 ppm of frequency precision – to USB DACs and digital players.

A unique laser-engraved serial number and the TEAC Reference OCXO logo on every OCXC case is proof of the rigorous quality inspection undertaken during the manufacturing process.

ppm=10–6, ppb=10–3

Frequency temperature characteristics: A value of frequency fluctuation caused by temperature change

Frequency precision: An actual frequency range 

Four BNC clock output connectors.

 

Thanks in advance, 

regards Andreas

[MarkusBarkus]

...there was a thread on this a few years back, FYI. Think it's the same item:

 

[ambre]

16 minutes ago, MarkusBarkus said:

...there was a thread on this a few years back, FYI. Think it's the same item:

 

Ok will read But questionnaires remains the same...suitable for EtherRegen? Y/n

[Superdad]

38 minutes ago, ambre said:

I just found a masterclock of Teac. Can you tell me if this masterclock as used as add-on for the Teac DAC UD 505 can also be used for my EtherRegen?

 

9 minutes ago, MarkusBarkus said:

...there was a thread on this a few years back, FYI. Think it's the same item:

 

Sadly that other thread had near-zero useful information about this clock—other than that it appears it can be purchased for much less that the retail price. 

 

However, here are the relevant bits I was able to find on the Teac’s datasheet PDF:

 

— Outputs are 50-Ohm, so you would want to use with 50-Ohm special request version of EtherREGEN.

 

— Output is sine wave, which will work with EtherREGEN but not as ideal as square wave.

 

— Teac does not specify phase-noise performance of the unit at all. They only specify the [irrelevant for audio applications] long term stability, so you really can not tell if this clock is any better than any other. We advise that folks not buy any external reference clock that does not at least state phase-noise performance at 10Hz offset from carrier. 

 

If if you are looking for a good performance clock at modest prices, look to Cybershaft. Even their entry level models (some as little as $700) each come with full individual calibration/test sheets and phase-noise plots. 

https://www.adark.co/collections/cybershaft/products/copy-of-cybershaft-ma-op13-op19-ocxo-10mhz-時鐘-vip

(I am pasting the link to Cybershaft entry series on their Hong Kong dealer’s site because specs are given in English at the bottom; Cybershaft’s pages are Japanese only.)

 

Also, AfterDark—a dealer for both UpTone and Cybershaft (plus others) has collaborated with someone to produce about a clock range with pretty good performance—starting at about $400:

https://www.adark.co/collections/project-giesemann-ocxo/products/afterdark-project-clayx-giesemann-ocxo-10mhz-時鐘

 

 

 

[ambre]

Superfast Superdad, 

 

Alex, thanks a lot for your quick responsie. Will have a look at products you mentioned.😀

 

Ps) Maybe an idea to make a shortlist from “ approved” resp. suitable Masterclocks for the beautifull  EtherRegen?

 

 Very best regards, Andreas

[yy]

I have read the 20 pages of this topic, very interesting!

 

Thanks to @MartinT and Uptone team for all your inputs and advices.

 

I would like to try the adventure of a Master clock.

I have 2 devices with input clock, the ER (10Mhz) and a Merging NADAC (692KHz).

So if I understand well, I should purchased the Adjustable BG7TBL version with Square Wave and 75ohm output. Am I right?

 

https://www.aliexpress.com/item/4000152675395.html?spm=a2g0o.detail.1000060.3.12ff4761U71Mcc&gps-id=pcDetailBottomMoreThisSeller&scm=1007.13339.169870.0&scm_id=1007.13339.169870.0&scm-url=1007.13339.169870.0&pvid=7adebdb9-cf4d-4abd-89d8-de318c4676b6&_t=gps-id:pcDetailBottomMoreThisSeller,scm-url:1007.13339.169870.0,pvid:7adebdb9-cf4d-4abd-89d8-de318c4676b6,tpp_buckets:668%230%23131923%2376_668%23888%233325%2313_668%232846%238109%231935_668%232717%237564%23678_668%231000022185%231000066059%230_668%233468%2315616%23735

 

@Superdad I was wondering if you have received your BG7TBL clock?

Were you able to measured the phase-noise performance of the OCXO? Do specifications of the DAPU are true (-125dBc/Hz at 10Hz)

 

[R1200CL]

@yy Maybe your DAC should have a better clock ?

https://a.aliexpress.com/_mMO1YCd

75ohm output by BG7TBL 10MHz OCXO FREQUENCY STANDARD 3 channel square wave  clock Master Clock for your EtherREGEN

 

[Pro Jules]

That's a sweet deal above.