Adventures with Clock Cables


My Aurender N20 has a Word Clock BNC input and my MSB Discrete DAC has a Word Clock BNC output. Vince at MSB recommended that I connect these devices with a 75 ohm clock cable. This allows the MSB Clock to be the master and the Aurender Clock the slave. There is a selection within the Aurender Conductor app that allows you to select this synchrony.

Last year I tried this connection using a $35 75 ohm BNC cable from Blue Jeans and the result was easily heard. Smoother presentation and better soundstage. Two months ago I thought I would see what additional improvements I could get by upgrading the clock cable. I called The Cable Company, where I borrow all my cables, and spoke to Ethan who is quite knowledgeable. I was going to demo the Shunyata Theta cable but it was on loan. Ethen suggested I try the Alpha which was a lot more than the Theta but I figured at least let me see what this does. I was skeptical that any significant improvement would be worth the cost.

A day or two later the cable arrived and after swapping out the Blue Jeans I was shocked to hear a significant improvement specifically in soundstage transparency and overall refinement. Now I was curious at least to see what the Sigma and Omega versions would do.. These were a lot more than I wanted to spend but I decided to try them. After evaluating all three over a week I can say I preferred the Alpha. The Sigma and Omega I felt at least for my system had too much noise reduction that slightly damped the highs. So I ordered the Alpha. Once hearing it I could not go back to the Blue Jeans.

About two weeks later I received the new cable from Shunyata. The cable that I borrowed and still in my system was the previous version before the new X Series was introduced. So the new cable I got was a Alpha-X. To my delight this cable sounded even better than the one I borrowed. All of the characteristics of the original Alpha were subtly but noticeably enhanced. In other words it was even better.

Amazing to me this improved my system to this degree as the clock cable does not transmit any sound or audio information. Just timing. But apparently there is noise that rides along and adds jitter to the clock signal causing artifacts that are audible.

Anyway if you have an external clock call The Cable Company and borrow a few Shunyata clock cables and see for yourself what improvement you can net.

jfrmusic

Showing 5 responses by jfrmusic

@justubes2 

 

You described the issue I heard with the Sigma and Omega Clock cables. More subdued presentation because of additional noise filtering .  And yes the X version also added a more refined and laid back presentation but also noticeably improved soundstage, imaging and detail retrieval. 

@audphile1 

 

I just was just very skeptical that the quality of the Clock cable would have such an impact. Others had told me it would have minimal impact. Going in if I knew a very expensive clock cable would make a substantial difference then Shunyata would have been my first choice. 
 

I plan another post about my experiences with Shunyata ground cables

@daveteauk 

ChatGPT for the answer

Great question. The “75 ohms” rating of a BNC digital audio (or video) cable refers to the cable’s characteristic impedance, not its DC electrical resistance.

 

Here’s what that means:

 

  • Characteristic Impedance (75 Ω):
    This is a property of the cable as a transmission line, determined by the ratio of its inductance and capacitance per unit length (geometry + dielectric material). It describes how signals “see” the cable when traveling at high frequencies (like digital audio or clock signals).
  • Why It Matters for Clock Signals:
    A digital word clock is a high-frequency square wave (essentially RF-like in behavior). To keep the edges clean and avoid reflections, the cable’s impedance must match the source and load. In audio/video and word clock systems, that standard impedance is 75 Ω.
  • If Mismatched:
    If you used a 50 Ω or random coax instead of 75 Ω, the mismatch would cause signal reflections along the cable. That can smear clock edges, increase jitter, and degrade timing accuracy—something you don’t want in a high-end digital audio system.
  • DC Resistance vs. Characteristic Impedance:
    If you measured the cable with a multimeter, you might see less than 1 Ω end-to-end. That’s just copper resistance. The 75 Ω rating is not a resistance you can measure with a multimeter; it only appears when the cable is carrying high-frequency signals.

So, in short: the 75 ohms rating ensures proper transmission of fast clock edges with minimal distortion and reflection.

@justubes2 

 

I use the AES/XLR to connect the Aurender to the MSB. Originally had a Blue Jeans cable. I upgraded to a DH Labs. Tried a Shunyata Alpha but preferred the sound of the DH Labs. Also tried the DH Labs Silver Reference but found it too bright. 

@justubes2 

Compared to the DH Labs XLR AES cable the Shunyata Alpha did not sound as airy and open and yes slightly warmer. 
 

Definitely the Alpha X was superior to the previous version. Less noise and better imaging and detail while adding some refinement. It is not warmer or darker in any way