Hi

Should I expect power supplies to need break-in time?

Just added an XPS to my CDX and it is sounding thinner and brighter than expected.

Anyone have any views on this?

Cheers

Richard

Hi there Richard.Your description comes as no suprise and sums up most Naim equiptment.Electronics and the associated cables need time to burn in,usually a couple of weeks.Patience will have its reward and the symptoms you describe will disappear.

hope this helps hooch

Richard,
There are three main aspects to breaking-in Naim electronics;
1) Transistors (and tubes) sound better warm than cold. In 30 to 40 minutes, the duration of playing a record, this is usually achieved. It can be sped-up in power-amps by playing at higher volume levels.
2) Equalizing temperature of left and right channels comes next. If you notice the layout of Naim electronics, left and right PCBs are in close proximity ensuring very similar performance. This is importantant for tone, timing, and soundstage. Also observe that the Naim power-supplies have trasistors (rectifiers) sharing the same heat sinks. Because of the (intentional) design of the cases, Naim electronics can get warm inside very quickly. That is why running them with the cases removed sounds worse (and is dangerous). To answer your query about time expected in the XPS (and Flat, Hi, and Super) it can take as little as an hour of playing CDs.
3) The above two examples assume the owner is turning off the PS after a listening session. The final "break-in" of a Naim PS is the infamous polarizing of the capacitors which requires the power to be on at all times. This can take many days, though I've heard (and read here at "The Corner") others say months. Naim go through much testing to ensure proper mating of capacitors in their PSs to the extreme of "re-capping" older units as an upgrade. That is why Naim amps improve more than competitors after warm-up.
As an aside, though your symptoms of "bright" and "thin" don't reflect it, be sure your XPS is not directly above, below, or next to your CDX or pre-amp as this will not realize its full potential.

Happy Listening,
Ron The Mon

It took a couple of weeks with my XPS for me to stop noticing improvements in the sound (and that was an ex-demo purchase that had been burnt in by the dealer one year before).

I agree with the comment on positioning. Try and keep the XPS away from the Source and the Pre-Amp and keep it switched on.