[XavierP56]

Which external clock are you using with it ? Thanks !

 

[FredA]

I got a 2008 Morion MV89 from this ebay seller

https://www.ebay.ca/usr/queen*s_land?_trksid=p2060353.m2749.l2754

I am expecting a new clock tomorrow to replace the Morion:


https://www.adark.co/collections/pr...mann-ocxo-10mhz-x-triple-integrals-integrated

 

[Jackula]

https://www.adark.co/collections/pr...mann-ocxo-10mhz-x-triple-integrals-integrated

Nice, they are very good clocks and the only clocks i would consider getting besides Mutec and Cybershaft.

Are you getting them custom made with 50 ohms output? What grade?

 

[FredA]

Nice, they are very good clocks and the only clocks i would consider getting besides Mutec and Cybershaft.

Are you getting them custom made with 50 ohms output? What grade?

Yep,. I custom-ordered 2 50-ohm and 1 75-ohm. All square outputs. And i chose the top of the line Eva. If i get a significant upgrade (or not), i will report. So far, the feedbacks are very good on these clocks.

Adrian seem very knowledgeable, and he also makes cables. I had an hdmi cable included in the deal, looking forward to trying it as well.

 

[FredA]

Got my Afterdark Eva this morning, so it has been on for 9 hours straight.

Already, it performs very nicely. Lots of air, very smooth and awesome timbres. The cymbals are right on.

Upon receiving it, parts were loose in the box, including one in the enclosure. So i had to open it up. The chassis is basically empty!

See:

Notheless, it already beats the Morion clearly. Only had to put a couple of screws back on to fix things.

 

[XavierP56]

Hi FredA,

The R7HE requieres sine or square signals clocks ?
Musically, is there a big difference between the internal clock and your external clock ?
Thanks.

 

[PhMZ4]

Got my Afterdark Eva this morning, so it has been on for 9 hours straight.

Already, it performs very nicely. Lots of air, very smooth and awesome timbres. The cymbals are right on.

Upon receiving it, parts were loose in the box, including one in the enclosure. So i had to open it up. The chassis is basically empty!

See:



Notheless, it already beats the Morion clearly. Only had to put a couple of screws back on to fix things.

Bravo... that sounds very promising

I’m always stunned by external clocks, as good as they are in terms of improved performance to internal femtosecond clocks, the simple fact of transporting the signal, even with short cables, is already reducing this performance drastically by introducing new jitter, so the only explanation which comes to my mind is the time alignment of all components which brings even more SQ than just a ‘nearly perfect’ femtosecond internal clock, or did I miss something?

 

[sajunky]

Bravo... that sounds very promising

I’m always stunned by external clocks, as good as they are in terms of improved performance to internal femtosecond clocks, the simple fact of transporting the signal, even with short cables, is already reducing this performance drastically by introducing new jitter, so the only explanation which comes to my mind is the time alignment of all components which brings even more SQ than just a ‘nearly perfect’ femtosecond internal clock, or did I miss something?

You are right, synchronisation of all components in a chain is critical, but I would like to see in a forthcoming R-7mk2 a clock output instead of input (or both, but input is my priority). A backward synchronisation is more efficient, as internal clock is in a close proximity to a ladder, resulting a minimal jitter injection. I agree, it is a best place for a high precision clock.

 

[FredA]

Hi FredA,

The R7HE requieres sine or square signals clocks ?
Musically, is there a big difference between the internal clock and your external clock ?
Thanks.

You need an overall transparent setup to hear the difference, but it is a difference that is worth the investment IMO. Sounstaging/imaging and the general level of information is raised, and bass improves. Realism is enhanced.

Kingwa says using a square should be favored because of the implementation of the 10mhz input but a sine can give good results as well.

 

[FredA]

Bravo... that sounds very promising

I’m always stunned by external clocks, as good as they are in terms of improved performance to internal femtosecond clocks, the simple fact of transporting the signal, even with short cables, is already reducing this performance drastically by introducing new jitter, so the only explanation which comes to my mind is the time alignment of all components which brings even more SQ than just a ‘nearly perfect’ femtosecond internal clock, or did I miss something?

The loss in signal transport is not that big for a clock signal. It is way easier to carry than a more complex Spdif signal. The internal clocks are way inferior under 10Hz with regards to phase noise. The Eva is stated as - 121@1Hz and - 145dB@10hz. The best internal are at around - 100dB@10Hz. And most often not specced at 1Hz.

 

[DACLadder]

The R7HE requieres sine or square signals clocks ?
Musically, is there a big difference between the internal clock and your external clock ?

Audio GD converts 10M input signals to squarewave no matter whether sine or squarewave are connected. Kingwa told me that in his designs squarewave inputs should have less jitter. The slower rise and fall of the sinewave signal creates less precision in exactly where the clock transitions occur. This ambiguity is simply jitter.

Took me a while to wrap my head around how synthesized clocks can have lower phase noise than a crystal oscillator. First, Audio GD uses proprietary FPGA code clock generation that takes the 10M clock and makes 90M and 98M audio clocks. Kingwa does not use internal FPGA PLL resources as that would be really inferior. Somehow the synthesized clocks produce less phase noise at the all important 1Hz and 10Hz steps. The Accusilicon 90M and 98M phase noises are about -59dB/Hz at 1Hz and -90dB/Hz at 10Hz. You will not get -120dB/Hz at 1Hz output with -120db/Hz 10M input but all you have to do is beat the Accusilicon specs for it to benefit the audio. Higher frequency phase noises of the synthesised and Accusilicon clocks tend to converge at frequencies above 1Khz - each near the system noise floor.

Amazingly these 10M clocks are capable of producing synthesized clocks with less phase noise at 1Hz, 10Hz, and even 100Hz offsets versus crystals. You don't get something for nothing as it takes the very best 10M clocks to achieve better performance of the crystals. Kingwa says he uses his Mutec Ref 10 regularly so there is definitely something to the affect.

 

[sajunky]

^^^This.
@FredA had a wrong answer, I was going to write reply, but this one is good. As long it works, is fine. I am still voting for the external clock output in the forthcoming R-7mk2 in a case I want to feed back the internal clock.

 

[FredA]

One should realize that the results you get are very dependent on the clock used. And that timing is crucial for getting great sound.

In a way, each and every clock is like a equalizer, tuning each band slighly differently. The perfect clock gives a flat tonality. And great overall clarity.

 

[PhMZ4]

Thank you for sharing your precious knowledge and experience on this important topic... and I’m with you @sajunky, it would be very interesting to give it a try (internal clock output) and compare SQ to external clock setups, at least the PQR should be interesting.

Now, what is your view on clock manufacturer’ roadmap, will they bring in the upcoming 2-3 years some new designs making a quantic step forward, as if yes, it would be wise to wait for them to be released in terms of new gears investment ?

 

[XavierP56]

I have R7HE-2021 without external clock and it's so good. I could live with it for many years.