Master Clock for your EtherREGEN

[Clockmeister]

15 hours ago, Ricardo007 said:

Hello

Did anyone tried thé sotm master clock on ER ? 

 

Yes I have performed this task and can report it is a positive outcome, specifically with the sound staging and gives a more relaxed feel to the overall presentation.

[Clockmeister]

Hello Superdad

 

Like your products very much by the way 😎

 

With regard to the Crystek 575 clock, are you looking to replace this item in any up and coming re-engineering of the Ethernet regen at all?

 

While the specifications are quite good I have noticed a fair amount of harmonic noise does extended well into the 2Ghz territory in numerous products that use this device, which may possibly have an effect on surrounding circuitry?

 

Not a critique' just an observation.

 

Regards

 

DM

 

[Clockmeister]

Hello John

 

Thank you for replying always nice to hear the thoughts of the main designer's rational for the end product.

 

Indeed the faster the rise time on the leading edge the more desirable the accuracy of the potential jitter reduction as you have pointed out the harmonic content stretches higher up into the upper frequency domains. The Crystek 575 series does feature harmonics orders way over the 40th again dependant on fundamental frequency.

 

Some of the harmonics are not 'down in the mud' (say only -45dbm or lower) from the core number and are quite prevalent at frequencies that could interfere with logic controllers/FPGA' s/ power control circuits and regulation etc

 

Your very genuine and honest reply regarding a trade off of the best possible situation against clock accuracy (jitter attenuation/phase noise/ground bounce and potential contamination of surrounding circuit pathways and i/c devices is refreshing good.

 

One must also take into account the cost of the device and all these factors together and as I mentioned in my first post on this thread a nice product that works and very fair price a nice job John.

 

My thoughts are specifically geared towards the  Crystek clocks (usually because the specs do not tell the whole story) in the area of audio, having pretty decent experience of this oscillator in many audio applications and in each case improving the end sound quality by replacing the Crystek with a clock with a not so (theoretical) desirable leading edge definition yet much improved waveform width definition and reduced overshoot , more stable pulse width and obtained a far more beneficial end result in sound quality

 

Appreciate every situation andbinstallion is different John, however with today's densely packed, high performing low form factor packages with ever square mm accounted for compromises are made.

 

One overriding factor has come out of my many years experience with high speed serial data work is the quality of the power lines and incoming  power quality feeding the clock is as important if not more so than the specification of the clock itself.

 

One point you have made on this thread which many people would not have paid attention to is impedance matching of cables and circuit pathways and that signal reflections (transitions of signals  bouncing back and forth a defined number of times according to cable length, /LCR connector mis matches) does have a significant effect on the sound quality especially with any digital signal transfer interfaces and  clock data transmission lines

 

If I have time over the weekend I could set up a demonstration of 50 and 75 ohm cable connection resultant  mismatches and the effects on the waveform at the input connector of the device, also show how a 50/75 terminator doesn't really cure the problem and that genuine matched impedance terminations are the most desirable methods of achieving accurate results. Though again I appreciate that not all audio equipment is geared up for this premise as with everything that is built to price compromises are made.

 

DM

 

 

[Clockmeister]

41 minutes ago, JohnSwenson said:

The 575 does have its own dual regulated supply, and the only thing it drives is the clock synthesizer (which has its own regulators) which only outputs LVDS signals. All clock distribution is carefully impedance matched differential pairs (I had a special board stackup used that allowed continued impedance matching as pairs changed layers). The reclocking flops are fully differential including clock. The chips which have a single ended clock input have  a very low additive phase noise LVDS to CMOS converter right next to the clock pin. The result of all this is a system that is much less sensitive to ground noise than is usually seen.

 

That was really the whole reason for the EtherREGEN, produce much less ground plane noise in the first place, and have circuitry much less sensitive to what ground plane noise that is there. Unfortunately I can't do anything about what is inside the chips themselves. I spent 30 years designing power networks inside large high speed chips, I have a VERY good feeling for what that can do to jitter for the circuitry inside a chip. Unfortunately we can't afford to do a full custom chip for every function we need, so all I can do is choose ones where it looks like someone did a fairly decent job on the internal PG networks.

 

John S.

Hello John

 

I would expect nothing less and good engineering principles for eliminating as much internal electrical and outside connective signal noise as possible. Though as you say you can only address all of the potential hot spots you have identified within the remit of projects budget and the fact you have paid attention to ground plane noise is good, so many audio designers do not feel it relevant to pursue this avenue. So appreciate your more wide band approach to this product.

 

Rolling your own chips best solution however budgets way above this products pay grade I feel.

 

 

 

 

[Clockmeister]

7 hours ago, Ricardo007 said:

Hello Meister

I read from Alex Crespi from UpTone Audio that thé etherregen likes to see square waves and not sinewaves that's thé reason I asked thé question, thé Sotm master clock being sinewaves... I also have other SoTM products to "discipline" (but not in à dungeon) so I thought better for them to have an SoTM master... 

Actually hesitating to buy between Sotm Mutec and Cybershaft

Any help ? 🐸

Good Morning Ricardo:

 

There are usually two forms of audio clock outputs either a clipped sine wave or square wave each has there uses and applications.

 

In my experience with many audio devices I have found that not all products from the same stable produced the most desired results from a wide range of manufacturers and not just digital audio either.

 

I am fortunate to have access to dedicated test lab as well as some respectable audio equipment. I do personally own all of the above clocks you have mentioned including a Cyber shaft OPA21 and a Mutec ref 10 SE-120 plus a coupe of custom 10 Mhz units.

 

All of the above clocks have a positive effect to sound quality when used in the context of streamer/CD/PC DOB <> dac's/processors some greater than others.

 

With regard specifically to ether regen as  master word clock signal, again they all have a positive effect without question *caveat* if you run a high quality headphone set up, you results will be more intimidate with speakers it can be more subtle depending on the resolution of the system it is being used in.

 

Benefits can include but exclusive to, improved sound staging and stage depth, spatiality and instrument separation. Bass texture and detail is better along with a tighter feel to the bass and improved coherence. These have been my personal experience.

 

 

 

 

[Clockmeister]

For those interested in how not to implement a Crystek 575 clock correctly images below clearly show a before and after working out exactly what was amiss with this particular 100Mhz 575 clock in a well known digital to analogue converter. As you can clearly see, the quite high amplitude harmonic noise sitting on the analogue output of said dac before extending to 2Ghz and beyond. limited the span to 2Ghz although it extend up to 2.6Ghz but the amplitude was much lower. Although the images are only 30 seconds apart the solution had been worked out over a couple of days.

 

So before and engineering solutions were applied

 

 

 

 

 

 

This was after the solution was applied.

 

 

 

 

In this instance a three way approach was need to remove the bulk of the harmonic distortions, looking at both incoming ac, dc rail filtration and RF shielding methods

[Clockmeister]

I am sure Martin T will be able to enlighten you on how his BG7TBL clock helps in his system.

 

Below is a an image of one of those very 10Mhz clocks using a  75 Ohm 0.5m bnc lead being measured at 50Ohm (using the 50 ohm output on the clock)  you can clearly see the impudence mismatch and the resultant distorted square wave form.

 

Followed by a eye diagram again clearly visible is the cable mismatch finally the FFT plot of the resultant harmonic noise.

 

These clocks offer a respectable upgrade for your ether regen I would suggest the use of a ultra low noise power supply is essential with this device to bring out its potential.

 

 

 

 

 

 

[Clockmeister]

6 hours ago, LowMidHigh said:

 

I'm a lowly layman, who is guided by John"s views on such matters. 

. That topic was discussed when a proposal of equipping the ER with said toggle was floated up and   summarily rejected. I suppose Mutec offers two batteries of BNC ports, 50ohn and 75ohm respectively, for that reason. 

 

This point has been mooted about in many circles here in the UK impedence matcing is critical for accurate signal fidelity whatever area of electronics you may happen to work in. In audio design it is rarely taken into account, however though John S has taken the time to make the effort to account for these criteria.

 

In my own lab I use a Mutec Ref 10 SE-120 as a master 10Mhz reference  clock for the test equipment especially useful when performing multi domain analysis in both the time and frequency domains simultaneously. In essence using both the high specification digital oscilloscope and real time spectrum analyser together to see a wider range of signal infidelities happening instantaneously it's a very useful ability to have when looking at hard to find fast moving issues with circuits and rf receiver applications.

 

The Mutec also does make for a rather good audio clock as well as ones recides in the main system.  although all of the audio word clock connected turns are genuine 50 ohms which is a far more robust and desirable impedence pathway, however finding the correct matching terminations may not be do easy

 

 

 

 

 

[Clockmeister]

Hello AbAndgate

 

Old skool boolean logic been a while since collage for that one!

 

A great many DIY electronics enthusiasts tend to use  these impedance converting devices, its not really a complete solution if you are looking for a true impedance match.  Ideally all things being equal keeping the pathway the same Z all the wat through from Tx to Rx.

 

I appreciate however that most of the after-market clocks are specific 50 Ohms.

When we measure a 75 ohm impedance path ways and cables we use a set of true 75 Ohm calibration tools and have our VNA or TDR devices set to 75Ohm. Totally understand 99.7% of audio users are not going to have this facility.

 

What I can do is set up an example of a 75 ohm cable being used with 50 Ohm measurement parameters, this will give you an understanding of how the reflections can be seen on the waveform.

 

Think of it like a converter from SPDIF<>AES or single end to balanced always something lost in translation I feel.

 

Will it be better than a total mis match 50<>75? possibly yes, possibly no, sorry for not being more definitive.

 

 

[Clockmeister]

Hello LMH

 

Logic is a great for starting the process of investigation and exploration of an interesting subject.

 

Personally I not use any adapters in my audio system, from experience to much of a sonic compromise for myself.

 

In the lab unless a particular experiment calls for specific set of conditions that requires  adpters then they are not used

 

This evening I can perform those tests with the impedance cables and adapters

 

However with your Mutec you have the ability to try some basic tests for your self, the ref 10 has both 50 and 75 Ohm outputs

 

BNC outputs 1 & 2 are dedicated 75 Ohm and 3 to 8 are 50 Ohm assuming you are using a correctly terminated 75 Ohm cable for your connection between ref 10 and mc3

 

You could engage a 50 ohm output and swap the output cable  to mc3 and report back and see if you feel there is difference in the sound quality

 

 

 

 

 

 

[Clockmeister]

As promised some results from using impedance mis matched cables and adapters.

 

I used the lab's Mutec Ref10 SE-120 master clock as the signal generator, scope has been calibrated, all test cables 18Ghz reference ultra low loss 50 ohm, audio cables were 75 ohms matched. 50 Ohm adapter is an R&S reference 8Ghz model.

 

First images are a base line set, 50 ohm output, 50 ohm feed 50 ohm receiver, also I enhanced the waveform to highlight the very slight overshoot to give you an idea of  of a close up of the wave form top edge definition.

 

 

[Clockmeister]

Next set of images show a 50 ohm cable being fed a true 75 ohm signal to a 50 ohm receiver note the reduced PK<>PK voltage and difference in the top edge wave form

[Clockmeister]

Now a genuine 75 ohm audio clock cable using the 50 feed into a 50 ohm receiver plus the top edge definition again

[Clockmeister]

Last up 75ohm cable, 75 ohm feed i to a 50 Ohm receiver, the lastly  adapter added in to the chain for comparison.

 

As you can see the degradation of the wave form is pretty obvious, and especially with word clocks the wave form actually looks like a square wave form with very little deviations is the more ideal the situtaion

[Clockmeister]

LMH

 

For the incoming data stream not to trigger either the wave form would have to be very badly distorted on the leading edge or the overshoot would need to be in the high double figures.  another possible option could be the clock recovery circuit being of mediocre design with fairly high corner stone frequency and very average PLL ability this would lead to issues and a large increase in distorted sounds if not drop outs so pretty rare for this situation to happen

 

Yes the alignment of the audio data to word bit data would not be ideal at all, simply as the main timing (derived from the word clocking circuitry) would be sub optimal and therefore an increase in time interval error (TIE) would occur with out question

 

Any wave form deviation from the normal incoming wave form that point the circuit would usually see during normal operations can result in an in jitter.

 

These deviations are cause by the following:-

 

TRANSMISSION LINE problems, impedance mis matching all the whole line no just the cables or board connectors, circuit board embedded pathways, components in that circuit where inductorsm capacitors or resistors.

 

BANDWIDTH data line not being sufficiently capable of handling the full amount of transmitted data remember audio word clocks are a staple 10Mhz so a pretty low level data stream required, however if all of the those components that make that pathway are not up to the task then jitter will occur. We use a tool called an eye diagram to look at serial data transmission lanes and can determine by observing the decoded patterns where a great many issues actually line in the circuit.

 

CROSSTALK  pretty obvious where other signals which should be totally isolated from the clocking sections of device actually interferes with the clock for data circuit that is connected to the clock causing introduced noise which leads to unwanted induced jitter

 

 

Data generated jitter which is caused by bad programming at the core cpu or PFGA etc this can generate ISI (intersymbal interference) induced jitter and duty cycle distortion this is quite common in either highly complex devices where a lot of processing power is required to run a device and it takes a long time for total debug or in a simple device with novice programmer skills

 

We have special seial data analysis tools to look at all these types of jitter problems more  on that later

 

RANDOM NOISE

 

which is cause by thermal flunctations the higher the temperature the more jitter.

 

This next one can be difficult to understand ,shot noise which is the random movement of electrons within the circuit like black holes and large celestial bodies mbe moved by dark matter not a lot you can do to take into account for this issue!

 

Lastly in this section frequency noise or pink noise the lower the frequency the more noise is introduced into the design all if these items designs take into account when coming up with a new product so tradeoffs are going to happen

 

All of the above cited problems can cause data line data corruption problems which will lead to the Rx end of your data stream incorrectly reading the edge crossing if the data which will result in jitter factor of electronics life.

 

There are more items that need addressing with jitterwe have  just touched on the surface however that is for a later post.

 

 

[Clockmeister]

Good Morning AnAndGate

 

Thinking about at the above posts I should have constructed a finial post to condense this information into bullet points.

 

Ideal conditions:-

 

Zero compromise:-

 

Transmission 50 Ohm output <> 50 Ohm Cable <> 50 Ohm receive end terminal

 

Transmission 75 Ohm output <> 75 Ohm Cable <> 75 Ohm receive end terminal

 

Not so good:-

 

Transmission 50 Ohm output <> 75 Ohm Cable <> 50 Ohm receive end terminal

 

Transmission 75 Ohm output <> 50 Ohm Cable <> 75 Ohm receive end terminal

 

Transmission 75 Ohm output <> 75 Ohm Cable <> 50 Ohm receive end terminal

 

Transmission 50 Ohm output <> 75 Ohm Cable <> 75 Ohm receive end terminal

 

Least desirable:-

 

Transmission 50 Ohm output <> 75 Ohm Cable <> 50 Ohm <>  75 Ohm adapter at receive end terminal

 

Transmission 75 Ohm output <> 75 Ohm Cable <> 75 Ohm <>  50 Ohm adapter at receive end terminal

 

What you are attempting to achieve is removing as many of the reflection pathways as possible in the same way in your audio system you are trying to remove as much, electrical, mechanical, vibrational and radio reference noise as possible.

 

You make a comment on one of the results where the using a 75 Ohm cable on the 50 Ohm Tx & Rx  positions resulted in a not too dissimilar wave form than the ideal impedance matched example.

 

Later on I will delve onto some jitter analysis with eye diagrams to illustrate that even small amounts of deviation will not yield the  desired outcome. Also show how an ok looking square wave form can in fact had a multitude of sins.

 

Having spent a lot of years with this subject and many digital audio projects I can safely and happily share my thoughts, you can quite easily determine an impedance mismatch digital audio cable against the correctly matched item.

 

With clock cables this can manifest itself as less than ideal sound staging,  more diffuse vocal  placement, the timing is less coherent with an overall sense if it's not quite correct.

 

For those of you that use a a word clock and have genuine impedance matched cables, just try changing it for say a normal analogue cable of the same termination or a 50Ohm lab cable. Let us know what you feel.

 

Sorry back to the subject of adapters an issue personally I will not compromise on in any form in my professional and audio life.

 

Yesterday I received a large delivery of supplies for a new project I am working on and along with the components with another small box inside was pair of matching 50<>75 balun's BNC terminated for another project which has been on the back burner due to myself needing to construct a test rig for characterizing insertion loss for a/c mains common mode filters.

 

This means I have how some rather decent 50<>75 Ohm isolation transformers so this may work out to an acceptable compromise for some individuals.

 

These are NOT audio products but genuine lab test standard isolation transformers with impedance transitions by a company called North Hills if I have time today I will test it for you.

 

Below is wave form analysis of a Mutec MC3+ in word clock output mode using 176.4Khz files this will give you an idea of  how some smaller companies and individuals actually go into deeper investigations with there research and designing stages for their products I suspect Uptone have this philosophy as well.

 

[Clockmeister]

AnAndGate

 

Mutec's MC3 is a word clock generator with outputs that mirror the incoming audio data sample rate it automatically changes rates according to the file sample rates

This uses the pcm reclocking feature to generate the outgoing word clock rate.

 

I believe  Martin T uses his Aliexpress sourced 10Mhz clock to slave both the Ether regen and Mutec MC3 with a master 10 Mhz signal directly from that clock.

 

The Mutec can be used as clocking distribution hub however the sample rates are derived from the incoming pcm data via one of its five different format inputs.

 

Brands such as Esoteric and Dcs can utilise the word clock output sample rates by using the outgoing extracted word clock go their individual WC inputs

 

Dcs have the added complexity of having two word clock sample rates  one at direct multiples of 44,1khz the other at multiples of 48Khz.

 

Each word clock lane automatically detects its the desired sample rate and selects the appropriate clock lane for the correct  SR multiple for the required file based playback  or incoming subscription service stream rate

[Clockmeister]

On 3/15/2021 at 4:37 PM, R1200CL said:

 

I think the only true answer to this is by certain measurements by specific clocks with EtherRegen. 
My understanding this may be a time consuming process. I don’t know.
 

 @Clockmeister Are you someone that can help in this matter ?
 

The implementation of square wave also matters. Correct ?

I’ve asked also isn’t it better to implement square wave conversion on the receiver side ?

And if not, why ?

 

The measurements I’m really interested in when you’re using the B to A setup, as it has been said long time ago that a clock is highly likely not to do any help in this configuration. 

 

 

 

 

 

Hello R1200CL

 

Its been along time since I posted here, apologies we have a lot of projects that are being finalized and a couple of posters on this forum have been lucky  to beta test them for us.

 

Ok, ideal clock output wave form, is there one?

 

This purely depends on what you are trying to achieve, in what part of circuit and how critical is radiated RF emissions and conducted harmonics going to effect the product itself.

 

In an ideal world (theoretical)  the straighter the leading edge of the square wave form the less time interval error can be potentially generated. So a great many clock manufacturers plump for ultra fast rise times with high frequency clocks.

 

However in the majority of cases this can cause overshoot, ringing and negative width aberrations plus increased harmonic content. So you would need to deal with the side effects in order to produce a clock that would tick all the boxes.

 

For example one high regarded dac which used a Crystek 100Mhz ultra clock generated harmonic content up to 2.5Ghz (25th harmonics!) I replaced this with a 'lesser specification' sine wave clock and BUT better phase noise made a significant difference (positive) to the overall;l sound. In that particular case, this was due to poor original design of the clock/digital filtering/and receiver sections of that product. A satisfactory result was achieved by using a sideways fix, this will not work in with ever device, each item has its own irregularities and requires a specific fix in relation to that piece of audio's issues.

 

Having a less aggressive leading edge with result in greatly reduced harmonic transients, generally requires less Pk<>Pk swing. However it has its drawbacks which also need to be address for each case.

 

All the aftermarket reference audio clock manufacturers employ their own methodology based on their experience and understanding of the achievement goal. Much like dac's and amplifiers also speakers.

 

Which would I choose having owned, looked and improved pretty much all of the named units on this thread (plus a few more) I current own six clocks, Esoteric G-01rB, Antelope 10Mx, Drawmer, Cybershaft OPA-21A (with one of our own power supplies nice improvement) Mutec REf10, Mutec ref 10 SE-120 both with enhancements.

 

The latter reside in my personal system and one sits in my lab to lock my instruments together.

 

Each one of these clocks is very good, though they each produce different results, for example the Cybershaft is best suited to more laid back systems, it will give it a shot in the arm without question. The Mutec we feel suits more even handed systems more, the trailing note body, texture and decay are world class and the staging is prolific. It just makes you sit and listen to music for hours on end.

 

I fully appreciate that each person's experiences and views may well differ, and are equally valid for the individual concerned, so back to RC1200L question which is better square or sine?

 

From my experience a correctly implemented square wave form is preferable, like CD or records they are good and bad examples of both.

 

 

[Clockmeister]

2 hours ago, R1200CL said:

Thanks for a very diplomatic answer 😀

 

May I ask what cable and connectors you’re using ?

Hi 1200CL

 

I use our own cable and connectors for all signal transmissions in the system

 

One useful thing being a signal hound is observing cable reactions under dynamic conditions and results are sometimes intriguing and confusing 

[Clockmeister]

1 hour ago, Superdad said:

Hi David:

Wonderful to see you back here again!  

And my sincere apology for not have yet replied to you very nice e-mail--of June, 2020!  I see it every day in the middle of my in-box.

Looking forward to learning if any of your projects are going to be in commercial production this year.

Warmly.

--Alex Crespi

Hi Alex

 

Thanks for the warm welcome

 

This last 12 months have been insanely busy with new projects, equipment acquisitions and a new manufacturing site now secured

 

We can now design a new circuit board idea and have the prototype fully machined between 1 and 6 hours populated and ready for testing and pre compliance within 36 hours and production within one week with minimal rejigging

 

Will be adding a laser and water cutter shortly to join the neat 4 axis cnc machining station as well

 

Products

 

New streamer platform with AI derived data storage via pcie 5, a dac and three power amplifiers  and two pre amps

 

Modular high end construction with selectable modules for digital and analogue sections fully isolated and shielded coupled with our propitpratory power supplies snd regulation

 

So a great amount of work ahead!

 

Hence why I have been absent however a lot of your customer's hete in the UK like your products a great deal

 

Have made one or two changes to a couple of them as Martin T has stated decent product very fair cost

 

Will try and not be absent for so long now

 

 

 

 

[Clockmeister]

1 hour ago, Tokyokyoto said:

What is your viewpoint on these 7lbtyeca? clocks from china for <$100.00.  Are they worth the time?

 

Hello Tokyokyoto

 

The person to ask is Martin T he has a nice version of this type of clock and it performs very well

 

I have built many over the years not just for audio, a few bits of tidying up inside a quality regulator half decent lps and possibly a vonnevtor swap and you will have a smile on your face

 

For the outlay it is worth the effort 

[Clockmeister]

With any clock design the numbers will only tell you half the story.

Low phase noise here is a bonus, however remember the supply rail's noise is critical along with correct circuit board layout, output transmission lines,  electrical isolation 

 

Next you need to look at stability of the signal is an oven required or you going to slave a GPS signal etc.

 

The next generation RJ45  format is close to hand it revoles around a higher bandwidth twisted pair and greatly improved interfaces

[Clockmeister]

I am curious as to why you reinquire a filter for a correctly designed product?

 

Impedance matching is critical first stage including ALL transmission lines remember SIGNAL INTEGRITY first and foremost.

 

Cables measuring if you have to use a scope make sure you are entirely 75Ohm pathway equipment not 50, 1Mohm or 10Mohm

 

For TRUE cable measurements a VNA (Vector Network Analyser) is far more preferable and accurate

[Clockmeister]

5 minutes ago, PYP said:

In my case, I'm assuming that the Cybershaft is doing a very fine job and is well built (impedance matching is intact from clock to etherREGEN).    

 

If the $50 filter experiment yields any benefit, I will assume it is improving the performance of the cable (which I don't have the technical ability or equipment to measure).   I'm not expecting much, just satisfying my curiosity.   

Hello PYP

 

I also have a Cybershaft 21A (with a significantly improved power supply and internal upgradess I use in one of the smaller demo systems), I have found that cable selections with the vast majority of these clocks can deliver quite surprising results from both very  beneficial to piss poor.

 

For some time I used a genuine RF reference cable (18Ghz BW) using T-Flex 405 very good indeed besting many multi $K audiophile cables.Cost is around $200 dollars for 3 feet un-termiated . Happily use them in my lab for sub 6G work. For audio now I use a different cable, it doesn't quite match that cable for insertion loss or overshot, however it sounds superior without question. The downside is cost. However for you guys try something similar you maybe surprised.

 

My other issue is I require 68 clock cables for the studio/lab and music systems so I have tried one or two different cables over the years

 

 

[Clockmeister]

3 hours ago, Rasputin said:

I have found a huge difference among the bnc cables when used between DCS Rossini DAC and DCS clock, so the notion of a cable “cease  to matter” with a use of a filter goes against my  hearing experience, however I will try as advised in the John’s paper. But would you share which cable you have found to sound best for your studio? 

Hello Rasputin

 

We have a great many clients with DCS Vivaldi stacks as we affectionate call them and all of our customers use an aftermarket reference clock to 'time' the DCS Vivaldi clock.

 

A fair few use Transparent Opus BNC cables, others swear buy Crystal Cables  Absolute dream 75 Ohm bnc cables.

While other use an self constructed RG45 derivative.