Does a new cd transport require break-in time?

Well, if the gentleman’s response is accurate it would mean that the "<75 ohm" spec is a misstatement. So if either of you chooses to follow up with him, you might ask "then why does the spec say <75 ohms?"

Best regards,
-- Al

Rvpiano 11-12-2017
I don’t understand why the Gungnir doesn’t sound better with the Cambridge. I thought it would. Maybe it is a question of break in. Shrill is perhaps too strong a word for the problem with the sound. It just seems lacking in fullness.

Rvpiano 11-13-2017
Interestingly, the Cambridge really sounds great with the old Theta DS Pro Prime DAC — full-bodied and detailed. It should sound even better with the Gungy. But it sounds too analytical and cold, without depth.

A possible explanation might relate to the fact that the impedance of the CXC’s coaxial S/PDIF output is specified as "< 75 ohms." That is a strange specification. Ideally the impedance should be 75 ohms +/- some very tight tolerance, not "less than 75 ohms," which is what "<" denotes.

It is common for a manufacturer to not indicate a +/- tolerance, but in most cases what is stated is simply "75 ohms," not "< 75 ohms."

If in fact the impedance is substantially less than 75 ohms the resulting sonics can be expected to have considerable variation depending on the happenstance of the design of the DAC and probably also on the length and other characteristics of the cable that is being used.

You might want to contact Cambridge Audio and ask them **how much less** than 75 ohms the impedance is.

Good luck. Regards,
-- Al

RV, I’m thinking that it may not be coincidental that problems involving multiple components appear to have arisen during a time in which connections were being changed. The connections involving RCA connectors, for which there is a brief instant during insertion or removal when the signal pin is connected but the ground shell is not.

When you were changing connections was everything powered off completely, as opposed to just being in a standby mode? For example, was the power switch on the rear panel of the Gungnir DAC turned off?

Also, by any chance were cheater plugs being used on the AC plugs of any of these components, to defeat the AC safety ground connection. Which would mean that the chassis of the component would have been in a "floating" condition, at an uncontrolled potential (i.e., voltage), if the component had power applied but was not fully connected. Including during that brief instant I referred to above.

In any event, good luck as you proceed. Regards,
-- Al

Anything that changes the risetimes and falltimes of the output of the transport (i.e., the amount of time it takes the signal to change between its two voltage states), or that changes the amplitude or spectral characteristics of electrical noise that is riding on that signal, or that affects distortion of the signal waveform that will inevitably be present to at least a small degree, could conceivably end up affecting timing jitter at the point of D/A conversion in the separate DAC component. The degree of any such effects, if present at all, would certainly depend on the specific designs of the two components, and perhaps also on how they are interconnected and on how AC power is distributed to them (which in turn can affect ground loop-related noise).

But is it possible that breakin of the electrical and/or mechanical components in a transport could affect these characteristics of the output signal to an audibly significant degree? I don’t think any of us can answer that definitively, but I also don’t think the possibility can be categorically ruled out. On the other hand, though, it certainly seems possible, and in fact likely, that **some** reported findings of breakin phenomena are due to unrelated changes in the system (such as ongoing aging or breakin of other components), or in its environment (such as changes in AC line voltage or noise characteristics, or in ambient temperature). Not to mention the possibility of inaccurate recollection.

Personally, I don’t use a separate transport so I can’t speak from experience. And in any event I would by no means extrapolate experience with a particular transport/DAC combination to other designs and other systems. But given the foregoing my expectation is that the truth lies somewhere in the middle ground between the opposing points of view that tend to be expressed on such matters. In other words, IMO the answer to the original question is a definite "maybe." :-)

JMHO. Regards,
-- Al