I still have an all-Naim system, except that the venerable NAP 250 has been replaced by various DIY amps designed by Nelson Pass. Naim components work extremely well together (even to the point of using DIN connectors) and offer a well thought out path from a starter system to much higher end. My first system was a Naim NAC 72 preamp with the NAP 140 power amp, which was essentially a two-box integrated amp. I now have a Naim CDX 2 CD player, NDX network streamer and NAC 82 preamp. All powered by external power supplies that I built myself. One of the upgrade paths is adding external PSUs, which yield higher quality by separating internal power rails between different sections of the components and between channels. Hearing the improvement in sound quality by going dual-mono even in line level components was something of a revelation to me at the time, and has motivated me to maintain dual-mono throughout the amplification chain in my system.
Naim power amplifiers use what is sometimes called a fast Class B output stage. The output transistors are specially made for Naim, and sorted according to their final use. In terms of build quality and audio performance, they are comparable to some of the Pass Labs offerings. Their overall sound is clear and well balanced, and extremely good at reproducing the harmonic signatures of acoustic instruments and voice. With full dual-mono power, they are also exceptional at reproducing micro and macro dynamics, which contribute to what Naim aficionados refer to as Pace, Rhythm and Timing. Smoothness and liquidity is similar to the best of the vacuum tube amps. I continue to use their sound as a benchmark for my DIY builds.
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From the article (highlighted by me): If a manufacturer doesn't know how to state what wattage is...😱 Is he talking about a transconductance amp (I/V=Siemens or mho)?
"Why is voltage more important than wattage?"
"A recorded musical signal is stored as voltage from the microphone on. In order to reproduce that recorded musical signal exactly as it was captured, you need to be able to reproduce that voltage swing perfectly, especially when amplified. Wattage is a ratio of current to voltage. If you have all of the current capability in the world but your voltage swing is handicapped, you lose the ability to reproduce the true dynamic range of the musical signal as the artist intended it to be heard."
I know many people with Naim gear. What surprises me is over the years how MUCH they've increased in price (while at the same time, many of the audiophool brands have gone bust). You can easily spend $100K on an all Naim setup; not that 6 figure setups is uncommon in the high end audiophool arena.
My experience with Naim didn't interest me enough as my ears were not accustomed to their "house sound". Long ago i've auditioned their CDX + XPS cd player against my HHB CDR850+ (pro audio) and found little difference. Likewise with their NACA5 speaker cable vs my heavy gauge general multi-strand copper wire.
Here's the issue we face when going Class A. In a world where climate change and carbon footprints is the global agenda, Class A amplifiers are "not environmentally friendly". Can you imagine the Eco-Warriors coming out in protest if Costco were to sell 2kW heater power amps with only 50 watts of output but weighing 50lbs?
New equipment has gotten quite expensive. I think we have become somewhat spoiled by the low cost of the diyAudio kits. Remember that FirstWatt products cost as much as $3000 and Pass Labs products are far more than that.
Most of my equipment was purchased used or with trade in credit.
Most of my equipment was purchased used or with trade in credit.
Why 50 watts ? Got efficient speaker and 15 watts, even 10 watts will be plenty enough !
Anyway the biggest problem concerning climate change are vehicule exhaust, thermal power station and air conditionner. It will take a long time before the class of operation of audio power amplifier will be a concern !
You can have the scientific explanation for why class A is better, but I prefer this simple, eloquent answer form John Curl :
All else being equal the more Class A you have the better. We don’t need a
full Class A amplifier, because people don’t listen to full power levels all
the time. They really need only 10 Watts or so because that is where most
of our listening is done. However, getting that 10 Watts of Class A is really
quite a feat considering of the all other constraints of having 200 Watts
Class AB in reserve. The Class A portion is always smoother and better,
while the Class AB is always a bit rougher because it is against the law of
physics. It breaks the music into positive and negative cycles and then splices them back together. Only one side is working while the other side
isn’t... it’s the nature of the beast. You can sometimes see the transition on
a scope; it may not be very much but it will be there. It will also generate
more high order harmonics. By definition, Class AB is not as linear as
Class A, but it is certainly much more efficient. So it’s better and easier to
run as much Class A as possible.
That's consequent with Papa explanation on its First Watt articles that you want to choose between the quantity of 2nd or 3nd harmonics, but you don't want to deal with the higher order harmonics.
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I rarely need 1 watt. So obviously, even 20 watts classA amp is plenty.
All that BS about voltage swing is sales pitch mumbo jumbo.
Well put.
While I am no expert, I have even simpler explanation why ClassA is better.
Typical ClassA will have higher distortion, at full power, but the distortion at lower power goes down. Lower power, lower distortion, general trend is towards zero at zero power, off course, noise tend to affect the trend, but you get the idea. Its because nonexistent crossover distortion, since only one driving element is on all the time.
Typical classAB, on the other hand, has best lowest distortion at full power. Nice! Yeah, but who listens at full power? How much time, when you look at waveform, signal spends at full power? Just look at normal musical signal in any good software, I use sony soundforge, signal crosses zero all the time, 1kHz signal crosses zero 2000 times a second. Signal is constantly crossing the zero, as microphone membrane moves back and forth, as air pressure goes from positive to negative. As drum goes back and forth, as guitar string moves back and forth. Always up and down around zero.
Back to typical classAB amp, with extremely low distortion at peak of full power, but then, the distortion starts creeping up, as power goes down. At very low signal level, it can be substantial, and the trend is not towards zero. When signal is crossing from positive to negative, countless time a second, the distortion is high. Signal spends lots of time crossing, so there is a lot of distortion added.
Someone clever, not me, said, who cares how amplifier sounds at 100 watts, if it sounds like crap at 1 watt.
You may not need but others do. Less efficient speakers/larger spaces/ more inclination towards head banging. It's no sales pitch, a kW is very nice to have.
As much as i enjoy my 20W of SE class A, its power limitations are painfully obvious.
IMO, 95% of modern amplifier design is solving the riddle of heat/size vs performance. Sliding bias, Class D, unique enclosures...it's all about heat/size vs performance.
Pass stuff takes the other road and does not care about heat/size. That's why it's kind of a niche product...even among high end amplifiers which themselves are kind of a niche product.
Pass stuff takes the other road and does not care about heat/size. That's why it's kind of a niche product...even among high end amplifiers which themselves are kind of a niche product.
Efficient speakers? That alone can be summed up as being as unobtanium as Class A amplifiers themselves. While if your wallet is large enough - gone are the days where hifi show rooms would showcase 100db+ efficient speakers that were more common in the 60s and 70s (horn speaker systems - Altec Lansing / JBL /). This has ALL been attributed to the WAF and that living room spaces are smaller as houses become smaller (i'm not speaking for the ultra wealthy as they need not apply). Just go into any hifi shop and you'll see nothing but speakers in the sub-90 area of efficiency (and i've found many brands that do claim higher efficiency in the 90s are simply far from that figure). Laws of physics need apply, you need LARGE SPEAKERS to be more efficient. But to compensate for the range of 'deaf' speakers, hifi nowadays has been about boosting the output wattage in all different ways (ie Class D). I can assure you, it's far easier to stamp out chips than to rely on the wood worker's craftsmanship in building truly efficient speakers.
The other aspect is high SPL ability that is clean and clear and in live concert situations. Small, less efficient speakers will struggle to do 120db SPLs and you need a lot of wattage to pull this off but as I say, the boundaries of physics applies. The surface area of a woofer means a lot of Xmax when you want to go louder. Sure many people normally don't listen to high SPLs - likewise some people will never open up their sport car's high HP ability but i'm a sucker with power and I like to CRaNK THINGs UP!*&!^*&%%! 😀
Anotherwords for the common folk, the trend has been clear for the past 30 years, bye bye Class A and bye bye efficient speakers.
I accidentally omitted important fact, which I believe, I mentioned many times before. All my systems are biamplified, I only use classA amps for mid-tweeters. I use classAB (2x120 watts) on woofers (2x15" per side). This way I have plenty of headroom, yet from 150Hz up its all classA.
Using just one monstrous classA to power big fullrange speaker seems wasteful, sacrilegious, nonecological, unnecessary, old fashioned, and I am sure pretty soon to be illegal like incandescent light bulbs 🙂
When i went from halogen lights to LED, and from plasma TV to LED TV, i saved about 650W pr hour. My lights and TV are on a hell of a lot more then my amps. Maybe 10-16 hours a day. That's 45,5-72,8KW a week. While my amps are on for maybe 15-20 hours a week. I realy doubt i can save close to this no matter what class amps it is.
yup, I'm all LED too
besides that - TV is not ON in any significant amount of time
most important is that my Ebook reader is having great LEDs
🙂
besides that - TV is not ON in any significant amount of time
most important is that my Ebook reader is having great LEDs
🙂
It's true that higher efficency generally need more cabinet volume.
But if you can withstand some compromise, a 8'' fullrange efficient driver might be the solution.
Of course forget techo, dance and other music genre that rely on big low frequency. But with most acoustic music, folks, vocal, jazz and classical music it should do nicely.
And for your ears, please do not listen to 120 dB, continuous or peak.
But if you can withstand some compromise, a 8'' fullrange efficient driver might be the solution.
Of course forget techo, dance and other music genre that rely on big low frequency. But with most acoustic music, folks, vocal, jazz and classical music it should do nicely.
And for your ears, please do not listen to 120 dB, continuous or peak.
High efficency speakers are bloody expensive. You can easely get a lot of noise. They are big. No wonder the world goes the other way. Power is sheap. And you get less background noise with less efficient speakers. Higher WAF factor.
Normally electrical energy consumption is measured in kWh. Power is measured in W (or mW, kW, MW etc.)
Not all watts hit that hard, i have the impression that tube and class A watt is more efficient than class D. I still remember the day that on a reggae festival (Reggae Geel in Belgium) a 3kW tube system with oldskool wardrobe speakers (Valv-A-Tron hifi from the UK) overpowered a 40kW line array system with class D (powersoft) amplifiers...