Product: Flatcap 2x external power supply
Manufacturer: Naim Audio - UK
Cost: £565
Reviewer: Maarten van Casteren - TNT UK
Reviewed: November 2007

Introduction

I reviewed the wonderful Naim CD5x CD player a couple of months ago and found it to be the best CD player I'd ever had in my system. I very much liked its natural presentation and strong musical drive. After I'd finished the review I was given the opportunity to also try it with the Flatcap 2x external power supply, 'just to get the complete picture'. I had already tried the CD5x with the (older) Flatcap 2 in a friend's system, so I wasn't sure how much this would add to the experience, but I was keen enough to hang on to the CD5x for a bit longer to accept the offer.

When used with the CD5x player the Flatcap 2x will power the analogue output stages, while the CD5x's own power supply will still power the transport and all digital electronics. Actually, the Flatcap 2x can power two components and will normally also connect to the preamp in an all Naim setup. My earlier experience with the Flatcap 2 in my friend's system had already convinced me that this is a serious upgrade. Naim claim that the Flatcap 2x is even better, and in my system it didn't have to power a preamp at the same time, as my preamp is a passive Django transformer volume control.

Naim has always been a company that has highly valued the contribution of power supplies to sound quality. Adding external power supplies to preamps and CD players is the preferred way to upgrade, and Naim provide a complex system of 'upgrade paths' to get you from your initial system to their ultimate high-end setup. There's a lot to be said for that. Firstly, the contribution of the power supply to overall sound quality is recognised not only by Naim, but by quite a few other companies too. Secondly, it actually makes for a very cost effective upgrade. Suppose you own the CD5x and would like something even better. Buying a whole new CD player would cost you serious money: a player that is really better could easily cost double the £1500 you paid for your CD5x. Perhaps you will be lucky and get £1000 back for your CD5x. That would still mean the upgrade will cost you £2000. Compared to that the £565 for the Flatcap 2x looks like a bargain. If it really makes a worthwhile difference, that is.

The first impression was a little bit strange because the connectors at the back feel very loose, as if something has broken. On top of that I heard some hum after I had connected the Flatcap 2x to the CD5x. I emailed my contact at Naim and he assured me that the loose feeling on the connectors was intentional, to prevent microphonics. He also very much doubted that there was something wrong with the power supply, as Naim are very serious about testing their equipment before shipping it. So, I went back to my setup and noticed that I had used two different power chords for the CD5x and the Flatcap 2x. One of these chords contains an inductor, which I have found to be beneficial with some CD players. I had used this cable for the CD5x, as it would now only power digital circuitry, while the Flatcap would take care of all analogue parts. When I used the provided Naim mains cables for both the player as well as the power supply all hum was gone and I was left with a wonderful sounding system. Obviously my inductor had caused an electric potential difference between the player and the power supply. So, it does seem important to use identical mains leads for both.

Sound

The sound differences when the Flatcap 2x was added to the CD5x were obvious and completely beneficial. When I had tried the CD5x earlier in my friend's system, with a Flatcap 2, we noticed a general improvement in the performance of the player, but no real change in its personality. Used with the Flatcap 2x in my system, I did notice that the bottom end was somewhat stronger, creating a slightly warmer and more physical presentation. And, of course, all other aspects of the performance were improved too, just like in my friend's system. Overall, the whole picture was more precise, with better focus and more control.

Going back to the CD5x on its own after a couple of weeks proved the point. The player I was so impressed with only a few weeks ago now almost disappointed me! It sounded flatter, thinner and grainier than with the Flatcap 2x. It is amazing how quickly one gets used to a better source. It is also quite shocking how much improvement was still possible with a player that did produce the best sound from CD I had ever experienced in my system. One of the reasons to try the Naim CD5x, and the extra power supply, was to find out where the law of diminishing returns really sets in for CD players. The Flatcap 2x clearly proves that investing an additional £565 on top of a £1450 CD player can be very cost effective indeed! I really wish I could tell you that spending more that £1000 pounds on a CD player is pointless, but it simply isn't true. If anything, this exercise proves that we're not even near the point where additional investments are useless.

Conclusion

It is very simple, actually: this is not a CD player that can be upgraded with an external power supply, but a two box player that can be purchased in parts. The fact that the CD5x will perform very well on its own shouldn't tempt you to use it that way. It needs the Flatcap 2x to really sing. This is not an upgrade, it is an essential part of this player! If you own a CD5x without a Flatcap 2x you should seriously consider ordering one as soon as possible.