Naim power amplifier technology

Posted by: NJB on 13 October 2017

Hi, I should know this kind of stuff, but my excuse is that school was sone time ago.

I moved from an unregulated NAP200 to a regulated NAP250.2. I am curious about the design differences. Can anybody point me towards an article, post or review that can satisfy my curiosity without inducing brain freeze?

My rusty science says that it is all about maintaining a steady reference power supply, which the NAP200 does passively with capacitors and the 250.2 helps the capacitors with some active electronic regulation. My 250.2 uses analogue regulation whereas the 250DR uses a digital system, which is presumably better hence the rave reviews.

Of course, I might be wildly off track here.....

Posted on: 14 October 2017 by ianrobertm

DR is not 'Digital' - it stands for Discrete Regulator - meaning a Voltage Regulator made from discrete components - not a Voltage Regulator chip (eg an LM317, say).

The 250 (all variants) is unusual, compared to most power amps, in having regulated power supplies. All the regulation is analogue.

Posted on: 14 October 2017 by NJB

ianrobertm posted:
DR is not 'Digital' - it stands for Discrete Regulator - meaning a Voltage Regulator made from discrete components - not a Voltage Regulator chip (eg an LM317, say).
The 250 (all variants) is unusual, compared to most power amps, in having regulated power supplies. All the regulation is analogue.

That is interesting, albeit a little counter intuitive. I am used to circuits becoming simpler by reducing the component count and relying on IC technology. Discrete components, in my mind, hark back to the days of circuit temperature instability, component tolerances and performance variation. What you have described conjures up an image of Naim going back in technology to move forward in performance. I am sure that I have oversimplified the reality, again.

Posted on: 14 October 2017 by Simon-in-Suffolk

In a way the discrete vs composite or integrated is a little bit of a technical red herring... but it was a label used no doubt for marketing purposes for non technical people to understand,

The real benefit, as I see it, from the Naim ‘DR’ technology is they could do a bottom up re design of their regulators and lower the distortion and noise from the previously used National Semiconductor/TI devices... which I am sure as good as they are, are a little long in the tooth now.. and although I’m sure Naim hand selected the previous regulators, their own discrete versions are better optimised for (arguably most of) their products.

Posted on: 14 October 2017 by fatcat

The leap in performance Naim achieved with the DR regs is not down to the fact they are Discrete, it’s down to the fact they are based on different, more advanced principles/technologies. Although, using the word advanced is a little misleading, they’ve been in use for 20 or 30 years.

Google Walt Jung Super Regulators.

http://waltjung.org/PDFs/Regs_...igh_Perf_Audio_1.pdf

But, as Simon suggested Discrete, will outperform non discrete, in most applications.

Posted on: 14 October 2017 by Richard Dane

DR as applied to the power amps is a bit different to the power supplies. The regulated power amps were always discretely regulated - think of two similar power amps, one acting as regulator for the other - but "DR" in the case of the power amps brought some Statement developments down to the regular range.