Master Clock for your EtherREGEN

[Superdad]

5 hours ago, Clockmeister said:

Plus a retail audio outlet. We are also offical UK service agents for many high end brands and service a few distributors and many UK dealers. My main personal fun is pullling apart the BS in the audio. We have a very well equipped electronics lab, but this is used as a helping hand as well as your own ears.

 

Thanks David.  May we know the name of your retail and service firms? 

[AfterDark.]

On 7/31/2023 at 1:48 AM, Superdad said:

David is correct as usual.  AXTAL in Germany does offer OCXOs with guaranteed performance at that level (-142dBc/Hz @10Hz offset in a 10MHz module): https://www.axtal.com/cms/docs/doc91144.pdf

Long ago they quoted us about $350 each—if you order and pre-pay for 250 units and wait 18 weeks for delivery. 

Of course there is more to a great clock “box” than just the OCXO.  Still need good power supply, case, and we’ll done output circuitry if you are going to drive more than one output.

Mutec knows what they are doing and, given that they build in some dealer margin and a full firm of sales and support, I think this new REF10 Nano is going to offer exceptional value.  

 

Hi! Alex,

 

We noticed that AXTAL is not performing good at Short Term Stability (Allan Derivation) for some reasons.  The measurement of Allan Derivation is little way too high when compared below. This is not quite a same level when compared to Ref10 or others. 

 

The Typical measurement for AXTAL =  2.10 x E-12 in 1s interval.

 

Vs

 

The Typical measurement for OCXO = 5.93 x E-13 in 1s interval. 

 

This is one digit difference (E-12 vs E-13) Other OCXO has much lower measurement  as below graph in BLUE. 

 

We want to share some of the OCXO with same Phase Noise -142dBC/Hz @10Hz offset. The Allan Derivation is always positve correlated with Phase Noise Performance.

 

We suggest when puchase the OCXO product, it is always look for indvidual measurement of Phase Noise and Allan Derivation. This can ensure the sound quality will not be compromised. 

 

Thanks and have a nice weekend.
 

Best Regards,

Adrian

AfterDark. 

 

Background information: 

 

We would like share some information on how to choose the OCXO. There is two important factors which is account for sound quality.  The Phase Noise and  short-term stability (Allan Derivation). 

 

For audio application, the phase noise at 1Hz and 10Hz can indicate the trend or slope. From the above graph we measured -112dBC@1Hz in RED and -142dBC@10Hz in BLUE (the lower the better)

 

 

In order to optimally select the audio clock, we comprehensively evaluate with Symmetricom Flagship 5125A to analysis the phase noise characteristics and short-term stability (Allen dispersion) that can be determinate the OCXO grading accordingly.

 

The Allan Derivation  

 

This is another important measurement for Audio Application, the Allan Derivation is about the stability in frequency at very short time intervals e.g in 1s little second. The Allan variance is intended to estimate stability due to noise processes and not that of systematic errors or imperfections such as frequency drift or temperature effects. The Allan variance and Allan deviation describe frequency stability, i.e. the stability in frequency. We found this measure is positively correlated with Phase Noise measurement. E.g. OCXO with low Phase Noise figures, will have lower Allan Derivation. 

 

For audio application, the most important point is @ 1 sec = 5.93x10E13 (the lower the better) in BLUE.

Some more information with OCXO for references

[Discopants]

On 7/8/2023 at 5:10 AM, Jakenz said:

To acknowledge the thread topic I'm not yet an EtherRegen owner... Waiting for the ER 2 release, but would suggest ER owners might wish to try fo.Q damping on their ERs given how potent an effect it has on my LHY switch.

I'm a big fan of fo.q both the thick and thin stuff which you can wrap around cables an uneven surfaces. I also employ lots of black ravioli pads, bases and footers on my whole system. Very noticeable improvement in bass and soundstage.

[Dandou]

SH-22K seems to have no effect on EtherREGEN. 

[MartinT]

My ER is on Black Ravioli Pads with a heatsink on top and a granite coaster on that, topped with a Schramm weight.

 

It's not moving anywhere.

[Kobolt_Cortado]

Hello there! 

 

I just registered on the forum but I have been reading it since the fall of 2020 when I got my EtherRegen. 

Thanks to all of you who are contributing here. It is both interesting and informative. 

 

I have the BG7TBL clock and it has had quite an impressive effect on my setup (Naim ND555). I have been pondering a Mutec Ref10 for a while and will probably get the nano version now coming out. And down the line the ER-2. So my idea is to try to cascade my first ER with the ER-2. 

 

So my question: Will it make sense (technically) to use the Mutec nano clock on both EtherRegens? 

Or would it make more sense to use the BG7TBL clock on ER-1 and the Mutec on ER-2? 

 

The Clock and ER are each powered by a Farad Super 3. 

[MartinT]

Unless you know the Mutec outputs are isolated, you don't want to short the two ER moats together with a common clock. Equally, don't use a common LPSU.

 

I use two grades of AfterDark clock, a King for the ER and an Emperor Triple Crown for the DDC/DAC. Use the best clock closest to the DAC.

[dbastin]

6 hours ago, MartinT said:

Unless you know the Mutec outputs are isolated, you don't want to short the two ER moats together with a common clock. Equally, don't use a common LPSU.

@Kobolt_Cortado

In case you don't quite understand the 'short', using the same clock provides an alternative route for noise to bypass the isolation (transformers, moats, etc), depending on how your gear is arranged.

 

For example, given the clock conne tion is on Side B, noise could travel ER 1 Side B > clock > ER 2 Side B.

 

If you use the same power supply for the clock and ER  It could be ER 1 Side A > PSU > clock > ER 2 Side B.

 

Well, that is my understanding.

[Kobolt_Cortado]

Thanks for your replies!

 

It says the following on the Mutec website:

Galvanic isolation of the independently switchable BNC clock outputs for optimum interference immunity

 

According to the Norwegian distributor Mutec has received quite a lot of preorders. Hopefully someone will report their experiences on this forum in a little while. 

[GryphonGuy]

Having purchased a couple of Mutec devices, I have absolute confidence in Mutec. You can also have confidence in any consulting you do with them and their highly customer-focussed business model. I am not associated with Mutec in any way. I am talking from a customer's perspective in Asia dealing with this European company.

The Ref10 SE120 clock is just in another world/league to the rest of the industry. The standard Ref10 is the bigger brother to this new cutdown Nano version. The Ref10 was already industry-leading before they created the 120.

You should notice more precise locations of instruments in the soundstage, great depth (because the timing is more accurate), better transient presentation, more natural timbre of instruments, ability to tell how big the venue was in the recording or the engineer made it with reverb etc.

 

I am sure the new Nano Mutec will be a huge success for them. I am even thinking of purchasing for a new listening room I am in the process of setting up should the Dante/AES67 timing protocol not be a success in the remote location.

 

Regards

GG

[Clockmeister]

I would agree and I use two of them in the electroncs lab to slave my analysers including a UXA signal analyser as well in the audio systems which it delivers vary natural and articuate music.

 

Would also suggest the the Cyber Shaft & Abendrot Audio are also very good

[russellbobby]

I am looking at the Mutec Nano also after seeing what a nice bump I got from the LHY OCK 2 paired with a EtherRegen and a Bricasti M3. 
Any USA dealers/distributors that I may want to contact? 
 

thanks in advance

[Kobolt_Cortado]

I finally added the Mini-Circuits BLP-10.7 + filter to the BG7TBL clock. 

 

I'm a bit baffled to hear a positive difference. It sure leads me to believe a Mutec Ref 10 nano will make sense. 

[Superdad]

On 9/11/2023 at 7:22 AM, Kobolt_Cortado said:

I finally added the Mini-Circuits BLP-10.7 + filter to the BG7TBL clock. 

 

I'm a bit baffled to hear a positive difference.

 

Assuming you are saying that you do hear a positive difference with the filter we recommended. Is that correct?  It should not be a surprise as we explain the reason for such--especially helpful for the cheaper clock boxes where their sine waves often have little spikes in the middle of the waveform due to power supply harmonics.

And we discuss and explain a lot of this in our paper: Considerations regarding usage of external reference clocks...

 

On 9/11/2023 at 7:22 AM, Kobolt_Cortado said:

 

It sure leads me to believe a Mutec Ref 10 nano will make sense. 

 

Knowing the quality and performance record of Mutec, the affordable new REF10 Nano is likely to be an excellent choice. One of the very few square wave clocks I would trust.

But unlike with sine wave--where impedance matching of clock/cable/device does not matter--for square wave you will benefit from paying attention to that and to pairing with a very low attenuation high bandwidth cable.

 

Cybershaft and AfterDark are also still producing worthwhile sine wave clocks, and cable considerations for those are much easier.

[doitttt]

how short can you make coax cable with bnc
I think maybe 100mm or 10cm
and meaning for the sound think of Capacitance 8pf

[realfx]

@JohnSwenson I have a question regarding the use of the unbuffered 75ohm output (OCXO output direct to BNC) of a BG7TBL connected in daisy chain to the unterminated input of a DDC through a T-BNC and then to the terminated 75ohm input of the EtherRegen. Is this possible with perfect performance? (I mean, without the clock signal suffering any loss or degradation)

 

Thanks!!

[JohnSwenson]

5 hours ago, realfx said:

@JohnSwenson I have a question regarding the use of the unbuffered 75ohm output (OCXO output direct to BNC) of a BG7TBL connected in daisy chain to the unterminated input of a DDC through a T-BNC and then to the terminated 75ohm input of the EtherRegen. Is this possible with perfect performance? (I mean, without the clock signal suffering any loss or degradation)

 

Thanks!!

This is called "bus architecture" and CAN work if everything has exactly the right impedance. If the impedances are not right you can get some nasty reflections that can mess things up. If the output is a sine wave you have a fairly decent of it working, if it is a square wave the probability of it working very well is low. Primarily because the BG7TBL clocks very rarely have the actual impedance they are supposed to have. I don't have yours and I haven't measured it, but the one I have is nowhere near the impedance it says on the case.  

 

John S.

[realfx]

52 minutes ago, JohnSwenson said:

This is called "bus architecture" and CAN work if everything has exactly the right impedance. If the impedances are not right you can get some nasty reflections that can mess things up. If the output is a sine wave you have a fairly decent of it working, if it is a square wave the probability of it working very well is low. Primarily because the BG7TBL clocks very rarely have the actual impedance they are supposed to have. I don't have yours and I haven't measured it, but the one I have is nowhere near the impedance it says on the case.  

 

John S.

Thanks!!

Let me ask you a last question. Assuming the clock has really a 75ohm impedance output (I’m planning to upgrade the clock to an Afterdark Clock that I think are higher quality than BG7TBL clocks), would it be possible to use one mini-circuits filter in the unterminated DDC input (being the filter in the DDC plugged directly in the DDC’s input BNC and then the T-BNC plugged to the filter) and another filter in the terminated 75ohm EtherRegen input?

 

Thanks again!

[JohnSwenson]

1 hour ago, realfx said:

Thanks!!

Let me ask you a last question. Assuming the clock has really a 75ohm impedance output (I’m planning to upgrade the clock to an Afterdark Clock that I think are higher quality than BG7TBL clocks), would it be possible to use one mini-circuits filter in the unterminated DDC input (being the filter in the DDC plugged directly in the DDC’s input BNC and then the T-BNC plugged to the filter) and another filter in the terminated 75ohm EtherRegen input?

 

Thanks again!

Nope that won't work, the filters are designed to work into a specific impedance, feeding one into a very high impedance will not do what you want.

John S.

[realfx]

45 minutes ago, JohnSwenson said:

Nope that won't work, the filters are designed to work into a specific impedance, feeding one into a very high impedance will not do what you want.

John S.

Thanks!!🍻

[justubes]

I am trying to find out if a Mutec reference se120 clock used as a  master and reference for a 22/24 or 45/49 mhz pair internal clocks (likewise for a 25mhz clock).

 

How much will it matter to use the best/lowest phase noise pair internal clocks in this instance.

 

Which would be a a priority for upgrade for best results or of more importance.

[JohnSwenson]

13 hours ago, justubes said:

I am trying to find out if a Mutec reference se120 clock used as a  master and reference for a 22/24 or 45/49 mhz pair internal clocks (likewise for a 25mhz clock).

 

How much will it matter to use the best/lowest phase noise pair internal clocks in this instance.

 

Which would be a a priority for upgrade for best results or of more importance.

Does the equipment have a clock synthesizer? You need some form of clock synthesizer to get those frequencies from the Mutec. If the device that uses those clocks has built in frequency synthesizers it depends on what the internal clock is and how good the synthesizers are. If the device does not have a synthesizer inside then you need an external one. These can vary all over the place. If you have good synthesizers then a Mutec driving them will probably be better than what you will commonly have inside the device. Without some model numbers there is no way to make any attempt at answering this question. If the driven device does not have clock synthesizers that can run from an eternal reference, then what synthesizers are you looking at?

 

For example the ER includes a clock synthesizer that generates the required frequencies from an external clock, it's built in so an external synthesizer is not required.

 

John S.

[justubes]

Hi John,

 

Thanks for your questions.

 

I believe some dacs  have external 10m inputs to help or prove the performancenof the clock inbuilt, dual frequency pairs of say 22/24mhz or 45/49mhz to cover these frequencies for digital sample rates. 

 

Would these also have a sythesizer, in which if externally clocked would not need a sythesizer since there are a pair of clocks and would tjen not require a synthesizer because there are the 2 audio clocks already.

 

Or will it make these internal 22/24 or 45/49 clocks redundant?

[Clockmeister]

This would be an FDN frequency dividing network.  As John has pointed out. However every time you use one of these to change / split the frequency you will incur noise and artefacts you really do not wish to have imho, some of these can be mitigated however not all.

Many of the chifi dac's use a 100Mhz master clock generator (some synthesised) which is then broken down (internally via FDN etc) to the required sample frequency for the incoming audio serial data rates.

 

The Mutec ref10-SE-120 uses a single frequency 10Mhz OXCO clock (Not Axtal) to generate its ultra-pure low phase noise reference 10Mhz signal. I recently designed an FDN/Synthetisers one for a Merging dac which uses 625Khz Master clock input frequency.

 

If you are referring to the individual sample rates such as 44.1-768Khz such as dcs et al, then usually the SE-120 or similar is used to slave the companies proprietary word clock device.

 

I did some serial data measurements not so long ago on the SE-120 see below. I know Leo Bodnar is in the process of purchasing either a R&S FSWP or Keysight UXA for ultra precise phase noise measurements. I have something a wee bit special coming for this every purpose towards December that will sort the wheat from the chaff as far as genuine clock measurements go.

 

John, I know has a phase station which is very fine tool for this also and he is well versed in PN measurements no question.

 

[justubes]

Thanks Clockmeister, takes a fair bit to digest.

 

"you are referring to the individual sample rates such as 44.1-768Khz such as dcs et al, then usually the SE-120 or similar is used to slave the companies proprietary word clock device"

 

I was wondering as opposed to a DDS Synthesized  frequencies.

 

If the master 10M's phase noise was 120db.

The proprietary wordclock 100db. 

 

How would one rate in order of overall importance /phase noise if

 

A)10M clock at 120db  slaving a word clock of 100db phase noise

 

B)10M clock at 115db slaving  a word clock of 105db

 

How would these compare.

 

In short, which clock would be of greater significance ?

10M or proprietary word clock in your experience?

 

Thanks for your comprehensive insight.