Advices on 10 mhz Clocks

@lanx0003 Good luck with your decision.  I probably won't be checking posts for the foreseeable future.  Feel free to PM me if you have questions that I might be able to answer. 

@lanx0003 interesting.  All I know is that I'm really liking what I hear. There was no extra brightness or harshness with the square wave connection. It works well with my gear. You cannot locate the speakers.  It's impressive. 

@baylinor sorry you didn't like October Project. You probably wouldn't like a lot of my favorites.  I often see albums recommended and I try them and think "yuk".  Lol.  It's interesting that we all like different things. 

Very interesting that both of you are hearing more detail, so I did some digging to explore why that might be. It turns out that a perfect square wave is the sum of an infinite series of sine waves at the fundamental frequency and its odd harmonics. See the reference below. https://www.prosoundtraining.com/2010/03/13/square-waves-and-dc-content/  Mathematically, it can be expressed as:

Square wave (10 MHz) = Sum( n⋅sin(2π⋅(2n-1) ⋅ 10MHz) / (2n-1) ), n=1,…,inf

The higher the order of the harmonic frequencies, the sharper the edges of the square wave. These sharp edges more precisely define the timing information in a digital audio stream, which can lead to the perception of greater detail in the sound.

@sls883 

No go for once blue to my tastes. However, I am glad you mentioned liking square wave best because it got me to try it again. With my brand new Townshend Allegri Reference mk2 100% passive preamp,  square wave seems to bring out some of the liveliness you lose with a passive pre over an active one. I love the incredible detail of the passive but it loses some of the forwardness of the sound. Square wave gives me that back. The sound got bigger. As always, EVERYTHING is always system dependent. What also got me to try it again is listening to vinyl. With an active pre I always kept my phono stage on 450 ohms for the Lyra Kleos. With the passive pre I also felt a bit of a loss in forwardness so I raised it to 520 ohms, et voila, same improvement. The key is to know your system inside out to be able to figure out the small details that can make big differences. If I don't get listening fatigue, I will keep it on square.

Wanted to thank you for giving me the idea of trying it again.

@lordmelton Thanks for the information.  Before I saw your post, I had already ordered a pair of 3 foot cables. I hadn't thought about it before today, but it makes sense that they should be the same length. 

@sls883 

Clock cables should be one meter and all the same length and identical models from the same manufacturer.

For economy cables try Shenzen Audio and Denafrips.

High end cables are $1k+

https://cybershaft.shop/

I initially needed 4 ft cables, but after rearranging my gear, I have one 18 inch cable and one 4 ft cable.  I could get by with a 3ft cable instead of 4ft, but 2ft wouldn't be quite long enough.

I don't know of any reason to use the same cable length? 

@sls883  Thx. Great, it is shielded.  What is length you used?

@lordmelton The 10Mhz master clock can not be used to directly run the DAC because it is not divisible by 44.1khz or 48khz. Its frequency needs to be internally converted to 45.1584Mhz and 49.152Mhz word clocks that a DAC needs to process the audio data stream through the PLL (Phase-Locked Loop) system.  I think Denafrips / DCS use native clocks directly to avoid PLL-based conversion or internal reclocking.

Goldensound actually demonstrates the jitter (short-term timing) performance is actually worse when 10Mhz clock is brought in as a reference, as you have also touched on.

However, the intention discussed here is to use a more stable long-term 10 MHz master clock to synchronize multiple components—such as the DDC (or switch/streamer) and DAC—as a shared reference, rather than clocking just the DDC or DAC alone. The listening impressions shared by @sls883 support this approach. I’ve also explained the rationale in the post mentioned above.

https://www.ebay.com/itm/385210385191?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=eA-ewD9lQt-&sssrc=4429486&ssuid=r8DBhqOeT52&var=&widget_ver=artemis&media=COPY

This is what I use for clock cables.  I haven't tried anything else. 

@lanx0003 

You mentioned GoldenSound. If you go through his videos he experimented with clocking a DAC and the benefit was zero. Clocking other components before their signal gets to the DAC ensures a pristine signal for the DAC to process.

Denafrips and DCS use twin WORD Clock connections at 44 and 48 kHz. These are basically nonsense when a 10 MHz master clock is far superior and can be bought for comparative pennies. I believe companies that use WORD clock just want to tie you into their process.

@lanx0003 

Good call. I do remember a discussion about connecting both the dac and the DDC. This other guy was making the point I am making now. Back then I connected both just because I could but I don't remember thinking the sound improved since I hadn't tried it without the dac connection. However I then started researching the matter and became convinced he was onto something. I no longer use a Gustard dac and my new Tubadour V does not accept an external clock, so it is no longer an issue for me. In the end I believe a master clock will only improve the sound if it clocks multiple units. In my case I still use it because both my ethernet LHY SW10 switch and U18 DDC accept an external clock. 

@oddiofyl I do like the individual impedance switch on the OCK-2—it provides some flexibility, even though I don’t have that many devices to hook up. Thank you for introducing the Mutec MC3+. I’m currently deciding on a DDC (SU-2, SU-6, U18, etc.) as well.

According to GoldenSound’s measurements, the jitter output from the MC3+ via RCA (407 ps RMS / 927 ps peak) is higher than the SU-2 (86 ps RMS / 252 ps peak), while the U18 performs the worst (499 ps RMS / 1217 ps peak). So far, I’m leaning toward the SU-2. Electrical noise appears to be comparable among these units. While there are no measurements for optical output, the jitter performance from the MC3+’s AES output is better.

Thanks @pinwa also for the info on the 50-ohm BNC cable—I’ll need one if I go with these “audiophile” clocks, since what I have now is a Belden 1649A, which is rated at 75 ohms.

Beyond these technical considerations, the puzzle I’m trying to solve—raised by @baylinor —is whether connecting the clock to both the DDC and DAC results in better sound. I understand @baylinor’s point: that with an I²S connection, the DAC’s clock is effectively slaved to the DDC. However, I’ve received feedback from others such as @sls883 suggesting that dual connection (clock to both DDC and DAC) results in better perceived sound quality.  Also, @baylinor, I recall you have attested in a previous post a while ago that you trust your ears perceiving improved sound with both connected, isn’t it or I have mistakened?

*** I think the main reason is that Gustard components like the X30 or X26 III are among the few DACs that can be properly slaved to a 10MHz clock when the REF clock setting is switched to “External.” However, when timing information comes from the DDC via I²S, it’s unclear whether the X30 or X26 III will remain ’properly’ synchronized to the 10MHz clock feeding the DDC—especially if the DAC’s REF clock is set to the default “Internal”.  This could result in imperfect synchronization between the DDC and DAC.

I have it connected to both the U18 and X30. 

@sls883 The game changing moment came when you asked about using square wave outputs on the ock-2.

Please clarify, when you had that game changing moment, were you connecting Lhy to both U18 and X30 or just U18 alone?

@sls883 

Pop is not usually my cup of tea but I will check it out. My main three systems, vinyl, CD and streaming are basically on equal footing, quality and money wise. I make sure of that since I enjoy the three. I was able to edit my house of stereo system yesterday and updated it. You can check it out. Even my DVD Blu-ray TV system is pretty impressive with the Loki Max equalizer. 

@baylinor I played vinyl many years ago before cds came out .  A couple of years ago, I upgraded my vinyl playback system.  It's nice and sounds really good, but not better than digital.  It's a modest setup by high end standards. 

If you stream music, check out Once Blue by October Project. Really cool music, imo. 

@sls883 

It probably has to do that I was purely a vinyl guy for over 50 years before beginning to appreciate the virtues of digital. 

@baylinor I had read that the square wave output made some gear sound too bright.  In my system, everything sounds more real.  Piano, drums, bass guitar, etc.  No brightness, sibilance, etc. 

Obviously everybody's ears and systems are different. Square wave is overly bright for me, sine wave is how I roll. All 50 ohms btw. The choice of square wave vs sine wave makes it a winner on the C18. Two connections each.

We talked about my experience with the LHY ock-2 on another post. As mentioned, I noticed a slight improvement when using the ock-2 with my U18 ddc. I don't notice much difference using it with my Gustard X30 dac. 

The game changing moment came when you asked about using square wave outputs on the ock-2. I had not tried that, so I gave it a shot. This made a very noticeable improvement in clarity, separation of instruments, etc.  It's still connected that way.... 

I have the LHY OCK 2 and I think it is great.  It has improved everything I have hooked it up to.  Cables do matter.  The LMR 240 is fine for 50 Ohm.  The Harmonic-Technology DC III, 50 ohm is better but much more expensive.  I didn't compare 75 ohm cables that closely.  Oddly, and I think inexplicably, burn-in on the cables is a thing.  Just leave them connected and the clock and its gear running for a few days before you judge them.

I use the C18 to clock my ethernet switch AND DDC. A master clock only makes sense if your are trying to clock more than one component. The DDC will clock the DAC via I2s on its own. No need for a master clock in that case. Anyway, that's what my research on the matter told me. 

I have the LHY OCK 2.  I have a mix or 50 and 75 ohm gear.   I have a Mutec MC3+USB reclocker USB converter.  That has a 10m input and is also a master clock generator.   The Mutec is connected to my Lab 12 DAC 1 Ref via  a DH Labs coax.      

I also have the clock connected to a LHY SW 6 and my Teac VRDS 701t Transport.  

My digital sources sound great.  Crystal clear , I can listen a long time without fatigue 

I ordered 50 and 75 ohm bnc cables from Pasternack.   I was able to spec 50 ohm cable and connector and 75 ohm cable and conn.for each type.    This is important because not all cables are terminated with respect to impedance.