If you really want to test a cable correctly, you need to use a network analyzer. Then check it on the Smith chart to make sure it is at the right impedance without it going capacitive or inductive through the frequency sweep. The wider the frequency sweep it behaves, the better.
I’m well aware. That test I did was a simple one with the tools I had on hand at home at the time.
I had a Rossini Clock with a Rossini Apex for a few years. I’m fairly confident I wouldn’t pass a ‘with Clock/without Clock’ blindfold test.
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It indeed is very personal. I clearly hear the difference with or without the Clock. As said before, also by others, if by accident the clock is off, I think the system is ‘broken’. The soundstage collapses, it does to me then sound recessed, less real.
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Same here,
Adding a clock to my dCS is very different from what I frequently encountered during my 25 years in Naim land when the upgrade was adding external power supplies.
The way I frequently describe it is “everything just drops” when the clock is removed. Of course the descriptive terms are personal however, imho and in my system, the difference is easily discernible.
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It was very interesting at Munich HiFi show last year (2024) when we had the headphone room down on the main floor and we had the Lina DAC, Bartok Headphone and Rossini DAC all set up with Lina Clock and Lina Headphone Amp and we were able to very easily do the “with and without clock” test with people across Lina / Bartok and Rossini …
Of course it’s a no-brainer to tell when the clock is switched on or off as there’s an interruption to playback but if the listener doesn’t know whether the clock is on or off and all they know is that it’s changed state then it was a very interesting “test” to do.
P
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And the results were…? We are all ears, so to speak.
Most people that wanted to try it (we didn’t just impose it on everyone that wanted to have a listen, just those that either specifically asked or showed curiosity in clocks and what they do) were able to pick out very easily when the clock was turned off (not just toggled) … the usual comment was “It sounds less focussed” (or something along those lines).
Turning on the clock was generally less easily picked out but turning it off was identified quite easily on the whole.
P
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Thank you! I’ve seen similar comments from others about the clock effect being noticeable when turning it off. I have a clock, but haven’t dared do the test. Another thought: perhaps we should both get out a bit more, as looking out of my office window I see a lovely Bank Holiday afternoon.
I did have the dogs down to the beach at 6am - does that count?
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Definitely! I went to see a newly-opened section of a local museum this morning, but beach beats museum I think.
Exactl - my findings as well
Maybe dealers need to change their demo process. Play the system with clock……and then turn it off. Easy sale! 
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But what clock cables were you using? 
The ones supplied with the Lina Clocks of course…
Unfortunately, imho and others, clock cables do make a difference.
Most likely due to @Anupc findings linked above. The supplied cables RG-59/U measured 88 Ohm / 85 Ohms. A Crystal Cable (sister company of my Siltech clock cables) measured 76 Ohms / 78 Ohms. dCS wants a 75 ohm cable.
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Dear Phil, do dCS master clock output and DAC clock input have impedance matching circuitries so that the impedance of clock cables is less crucial than we have always been thinking of?
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Hi @KTS
Confirming this with the R&D guys as I wanted to get the correct information for you…
“…we match the receiver (Wordclock In) to the nominal line impedance, this minimises the reflections back from to receiver to keep everything clean from its perspective. We drive the line (Wordclock Out) at an impedance lower than the line impedance to maximise signal level and thereby noise immunity and as there is no reflection coming back from the receiver then the lower impedance of the output doesn’t constitute a problem.”
I hope that helps.
P
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Thanks Phil,
That means we should strictly adhere to 75 Ohms.
Sorry - Does it?
I’m not the most technical here - but perhaps can you walk through the logic from what Phil said that got you to this definitive statement?
Certain word clocks and receivers on the market have impedance matching circuits to compensate cable impedance variations—–higher tolerance to cable variations.
dCS R&D guys said the impedance of Wordclock IN is matched to the nominal line impedance and OUT lower than the line impedance. Which means the impedances of IN and OUT are pretty much fixed——hence lower tolerance to variations.
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