I would enjoy hearing any technical insights about the design of the original 250 and its iterations to the current day. In particular, what do you think most contributed to it holding it’s own for a 30 year legacy? What technical elements give it the juju that creates fanatic followers?
Have other’s copied these innovations?
Thanks and if it’s been discussed to death already, please re-direct me.
Cheers,
Eric
(owner of a NC250)
I can’t say. I was introduced to Naim only since October 2023. However I now have the NC 250 and love it. I have a 300 series system.
Most, if not all, of the classic amps used the same basic circuit, it is very standard. Much of what then may seem like typical english quirkiness are actually very valid design decisions.
What made the amps different was the careful design around star-earthing and from this came the decision like the use DIN-contacts, the way they route the signal on a trip via the power-suppplies and from the power-supply to the power amps. But also the design of traces on the circuit boards to make sure nothing blocked earthing.
Another important decision was the power-suppplies which needs to be able to supply enough energy fast over the full frequency range.
They did other things like implementing the typical zobel protection by demanding the use of critical lengths of well specified speaker cables. I once had to repair my 135s after forgetting to check the speaker cables was properly connected.
I you find the archive with the old forum you will find a lot of information.
Fully regulated poweramp, unlike almost everything else
A fully regulated power amp refers to a power amplifier that uses a regulated power supply for its entire amplification section. In such designs, the power supply continuously adjusts its output to keep the voltage rails stable, regardless of variations in load (the demand from the speakers) or input voltage fluctuations. This contrasts with most power amplifiers, which use unregulated power supplies—meaning the voltage can sag or rise depending on how hard the amp is working or on incoming mains variations.
| Feature | Fully Regulated Power Amp | Conventional (Unregulated) Power Amp |
|---|---|---|
| Voltage Stability | High - Constant output | Moderate - Varies with load and supply |
| Audio Performance | Cleaner, tighter, less distortion at high output | Can suffer distortion/sag under heavy load |
| Complexity and Cost | High | Moderate to low |
| Efficiency | Lower (more heat dissipation) | Higher |
In essence, a fully regulated power amp is designed for maximum fidelity and consistency but at greater complexity and cost. It is most often found in high-end or specialist audio equipment, where these advantages outweigh the trade-offs.
Source Perplexity AI
Yes, probably the most unique thing about the NAP250 (as well as the 135s, 300, 500 etc.) is that it’s a fully regulated power amp. I remember during my early days at Naim when I asked what that was, it was explained to me as effectively two power amps where one acts purely to regulate the other to keep it within a very tightly defined performance envelope.
Of course there are other elements that are also part of the Naim DNA such as the very tight selection and matching of paired components, the move to designing and making their own custom output devices from NA001-NA009 (worth reading about the statement and the N009 development - very cool story), and great attention to detail with regard to the wiring and also, in later years attention spent on minimising deleterious microphonic effects on the circuitry.
That’s interesting Richard, continuous development etc. Do we have any information on the major technical developments with the NC range, particularly with reference to the 250 vs its predecessors?
There was a great deal posted by Steve Sells on the original New Classic thread on here, that might well be of interest in that regard. It’s worth going back through his posts - @110dB
Here’s just one of them..
I think prioritising listening and going with what sounded best rather than focusing on measurements was a key aspect of early Naim designs. And whilst this is not directly connected to the circuit/design, it was an underlying philosophy that was key and has become almost universally accepted that listening tests are key to choosing the design and should take precedence over measurements.
I think measurement is always important, but listening is critical. With the New Classics Steve talked about an instance of component choice where a component that measured slightly worse than the best actually sounded better in listening tests, so that’s what he went with. Listening repeatedly throughout development of a product is a key part of Naim’s R&D process.
I remember putting an oscilloscope on the power rails of a popular Japanese hifi system. You could see the waveform was similar to the output of the amplifier. I wasn’t driving it hard.
Also, the slew rate of the Naim power supplies is pretty good.
I have often thought that Naim is actually a power-supply company that gives you a power amp with that power supply.
I choose Naim based on look. It has a brutal utilitarian design and senses that hook me in. The fact that it is technically sound is just wonderful.
And this is exactly the reason I’m giving the current NC range a miss and holding out to whatever comes later. I thought maybe my initial reaction to the NC aesthetic would warm with familiarity. It hasn’t. Clearly the popularity shows that Naim actually got it right. But to me personally, I look at a NC 250 and think, “WTF were they thinking?”
I know I am in the minority, like you. But I feel the same.
I respect the time and effort that went into it…and it’s good for the brand…but I never thought Chrome Bumper looked anything but handsome and my SN3 & NDX 2 are exactly the modern, minimalist aesthetic that I wanted.
Glad to see New Classic gain success and acceptance, even if the styling isn’t for me.
I have had Naim boxes from every range from the CB onwards. I have mostly liked the current range and still do. One of the things that has been consistent across all Naim ranges is that they are all dust magnets. I do sometimes wonder if the Vereker family had shares in duster factories.
‘It has a brutal utilitarian design and senses that hook me in.’
Great one very well written.
I’m torn tho – as a designer myself the brutalist CB design (the bolt downs are even more ‘brutal’), I was in love at the first glance. But my girlfriend born in the late 90s thinks the chrome bumper defo outdated and largely prefer the Olive even that’s ‘technically dated’, which I love to death as well.
The classic/nc sounds really good, maybe the best in last 50 years but a bit too corporate looking, lack the flair we used to love.
Good thing I didn’t buy the NC 250 for its looks then. It sits in an open-backed cabinet, behind a door, where it can’t offend.
This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.