Naim invested alot in the Discrete Regulators which lowered the noise floor. These started in Statement amps and the technology was trickled down to the DR range.
The quality of components affects the quality of the power supply. This is why Naim use the best components they can source.
A related if naive question; if using an innuos or equivalent, effectively turning a nds into a dac only, what is the sonic contribution of the power supply?
ol.
Just for the “upgrade” wardens who may be getting ready to put me atop of their local bonfire next Tuesday night. I have a clear upgrade path for my system over the next however many years: XPSDR for the ndac, supercapdr for the 282. Then possibly move to 252 and 300dr.
@Dan_M describes it better. I can add a more naive description
You have ground and you have the voltage of the power supply. They are the reference levels, both must be absolutely stable relative to the music, the distance between them cannot move because that would change the distance to the music signal - which means distortion.
So the power supply voltage must stand and hold its level despite sudden short power-requests from the amplification stages. So basically the power supply must be more powerful than the amplification stages will ever need. And it must do it over the audible frequency range.
Take a constant bass-drum whack, add a constant hi-hat. If the bass-whack cause the power-supply voltage to duck that would hide any hi-hat at the same time. And boom there
goes your pace-rythm-and-timing that your Naim is so famous for. It will be harder to hear
what separation of instruments because a bad supply interferes and mush them together.
So the other components may add some coloration, who cares if you have a weak power-supply that hides and changes the musical content. A better power supply always improve your system … to a degree of course.
It might be worth looking at some pics of the insides of these power supplies. For example, inside a Flatcap there’s hardly anything inside it. Inside a Supercap is a massive toroidal transformer and banks of capacitors and regulators and full on wiring loom.
In a DAC we deal with very tiny levels for the least significant bits. A DAC often also receive high-frequency garbage from network components. So the demands in a DAC is both precision and a very wide frequency range. So dont just use any linear power-supply, it must also be very fast, With an NDS you dont need to worry, the Naim ones are very good.
Hopefully it helps to see what you get with the different power supplies and helps identify the critical components.
I am no expert on electronics but find it interesting how the power supplies work and what goes into the them. There’s been great work from Naim in the design and engineering of power supplies. Alot has been relatively unchanged for 30 years. The discrete regulators are one of the biggest changes in that time.
A box of a Flatcap (of any description) has a good deal more air space than a Supercap and it is true the Flatcap is a more minimalist design but the components that are there (including a toroidal transformer) such as caps and power management circuits (not DR though) are of good quality and do make a positive difference to what you may use it for such as a CD5 player power upgrade. In short a flatcap is still a high quality power supply but of course a HiCap and Supercap are superior improvements on the tech tree but they should be given the extra expense of them.
Having only recently acquired a NAP110 and CB HiCap, I was blown away by how heavy the HiCap was, way heavier than the 110. I can imagine it gives a connected NAC a very very good power supply.
External PSUs, prior to DR and vs an internal or a power amp’s one, provided:
A dedicated transformer
large capacitors
two separate rails of 24V vs the single rail of the internal/power amp’s one
In all PSUs old LM317 regulator chips were used with a simple implementation. Going up the ladder more selected regs were chosen.
DR technology has brought discrete circuits of Naim design for much quieter and stable V. A DR circuit is not based on an integrated but on discrete components.
External PSU on a CDP powers the analogue stage while the internal one is still in charge of drive, DAC, display and logic card. XPS and 555 are more complex PSUs with many regulated outputs that power various stages.