I agree Todd. It’s about what works for you.
I agree Todd. It’s about what works for you.
The Tale of four analogue amplifiers from a Stereophile review of the JBL 4367.
Unfortunately a digital amplifier was not included in the comparison but this review illustrates just why analogue amplifiers are very much a part of hi end sound reproduction.
Note wanting to provoke a flame contest but would a digital amplifier yield these remarks from a passionate music lover?
My tip is probably not. Sting’s a bit. But l prefer not to sugar coat it when a sizeable investment in time, money and effort is involved.
Sometimes it’s takes more than a ruthlessly accurate loudspeaker to enjoy high quality musical sound reproduction.
Having personally used a variety of class AB amplifiers, digital amplification by Bel Canto and several different class A amplifiers for over two decades l can say un categorically that class A amplification wins the hearts and the minds every time.
In my own experience a digital amplifier or processing can sound sterile. This sentiment is shared in the recording industry hence the use of analogue and digital processing.
The best of the best amplifiers l have experienced were the Pass Labs diy clones of the AX Series which use a super symmetry topology cancel residual distortion components without feedback. I actually sent Mr Pass a review of my clone and he said he passed it around the factory. These amplifiers run very hot with full continuous class A bias and draw significant power from your mains outlet. The result is music with utterly life like presentation.
It’s the starting point for the most revealing listening experience without being subjected to a ruthless loudspeaker so accurate its presentation is too analytical to be enjoyed.
Btw l do use a Lumin Streamer, Audio Labs CD playback and a Prime VPI TT with a Keseiki Purple Heart cartridge and an Ortofon Black Quintet cartridge. Occasionally a friend provides 15 inch master tape copies burnt to a HD via an Oppo player. That’s as real as it gets.
The limitations are then minimised. There is only you and the music.
With the Line Magnetic LM-845IA
The Line Magnetic brought out the loveliest and most realistic timbres from the 4367s and lent them much of its pellucid transparency. But regardless of whether I used the amplifier's 4- or 8-ohm taps, the combination made bass sound slightly rubbery and slow, alerting me that 22 are simply too few watts to take control of the JBLs' woofers. Lesson learned.
With the Pass Labs INT-60
Pass Labs claims that their integrated amplifier outputs 60W into 8 ohms and doesn't leave class-A until 30W. According to the illuminated meter on the front of the amp, it remained in class-A while driving the 4367s, even during loud crescendos. With the INT-60, the JBLs became sonic microscopes, unraveling every mix, no matter how busy. On the Frank Ocean track, the hiyaa-ing martial arts students, who can sometimes sound like white noise, were rendered with rare realism and presence. Even the subtle changes in air pressure at the beginning of certain tracks became easily audible. This sci-fi level of resolution proved fascinating, but I prefer champagne to water and soon began to long for more color and emotion.
With the Mark Levinson No.5805
At the Harman store in New York City, the 4367s are hooked up to this integrated amplifier, and I could quickly hear why. The two made a synergistic sound—more full bodied if not quite as resolving as with the Pass—that was propulsive and easy to listen to. The combination drew attention to the music's rhythmic lines and offered the most satisfying bass reproduction. On "Pink Matter," Charlie Hunter's electric bass came in with whiplash-inducing force and tunefulness. The Levinson's Bluetooth input and built-in DAC made it easy to listen to movies streamed from the Roku stick in my projector, which proved to be a blast through the JBLs.
With the Ayre AX-5 Twenty
When I connected the Ayre amplifier and Frank Ocean began to sing, I might have teared up. Compared to the Pass and Levinson, the Ayre subtly shifted my attention from the sound of Ocean's voice to the meaning of his words. In the bargain, it added more saturated tone colors and more distinct instrumental textures and timbres. Like the other solid state amps I listened to, it took full advantage of the 4367s' bass-making abilities and macrodynamic talents. This was the combination I found to be the most musically enlightening and the one I ended up listening to most.
Ian, I am at a loss here...
When you say "digital amp" are you referring to an amplifier that retains a PCM signal all the way to the final stage of amplification, or are you referring to an amplifier with a Class D power supply?
In my world any that is not analogue from the input to the output is digital. It can’t be anything else under known audio amplifier classes.
Common brands like Hypex, Purifi ect. I don’t see any confusion at all. They are all self oscillating amplifiers in some form or another.
Some amplifiers use a smps for efficiency because a linear power supply has losses in the form of heat. But the rest of it is analogue.
Incidentally l did read several “reviews” of Purifi latest offerings by Hifi online magazines such as 6Moons. My take is it’s still a work in progress. If l was ‘just’ a subjectivist audiophile running these popular wave guides and l owned a digital power amp like those mentioned above and a dsp active crossover l would be nervous or sceptical because you loose control over all the choices almost all audiophiles have.
That is the ability to select a signal path which is going to compliment your loudspeakers and your personal preferences. This has been part of selecting hifi components for the past five decades.
Loudspeaker fall into basically two categories of accuracy:
Clinical - piston range as in metal alloys, carbon fibre and ceramics
Euphoric - controlled break up such as paper, doped paper and polypropylene and miners filled polypropylene.
There is an overlap and this can be with textile / coated diaphragms or Mylar diaphragms or similar
Sometimes the paper cone woofer overlaps with the horn compression driver with is metal.
So the normal choice of analogue signal path offers the user a means of moderating the above characteristics one way or the other.
But if it’s all digital then you are going to find a greater contrast on so called good recording and bad recordings. This is because digital is a very black and white transfer function and the loudspeaker tracks this black and white perfectly. So the hifi listener is then going to be anguished over what to play next.
This is not hifi listening. . It’s surgical listening which is not the intent of fine hifi sound reproduction. That’s bad when what they really want to hear is the dynamic range, the micro dynamics, ambience and tonal shading of each recording. That is what jBL loudspeakers are renowned for.
The surgical listening is the role of the mix engineer with his very detailed near field monitors placed two or three feet away. The mastering engineer then basically ensures the recording is able to be recorded on the media (analogue or digital) and that all tracks have a consistency. Some tonal shaping is sometimes done. They listen to it on two or more pairs of loudspeakers to get an idea of how it might sound at home or in your car.
If a user is not interested in the bigger picture or they pay music to listen to loudspeakers that is their choice.
Originally Posted by toddalin
https://www.audioholics.com/audio-am...ital-amplifier
Looking at current consumer active loudspeaker offerings from Dynaudio and Elac there is a departure on the class of amplifiers used.
Dynaudio have had their toes in the water with a few iterations of an active consumer hifi loudspeakers. The original effort was full dsp with room correction. More recent iterations have tamed this back a notch. But still digital amplification,
https://dynaudio.com/discontinued-models/focus-
https://dynaudio.com/home-audio/focus/focus-10
Whereas Elac have taken a more conservative view.
https://www.elac.com/category/powered-speakers/
The reviews and feedback speak for the product.
Getting consumers preferences right takes a considered view of what matters to the consumers ears. If vanilla digital power amps were acceptable they would have gone the digital route. But they didn’t.
This approach resonates with my post above. Handing full control over to digital processing and amplification is not always the best avenue to success in hi fidelity sound reproduction.
‘Oh it sounds good but only on some recordings is not a consumer success story’. ‘It never was and never will be’.
Just because Class D amp involves a system similar to the way digital works, (i.e., pulse width modulation or such) it is not digital per se.
From Wiki:
Class-D amplifiers work by generating a train of rectangular pulses of fixed amplitude but varying width and separation. This modulation represents the amplitude variations of the analog audio input signal. In some implementations, the pulses are synchronized with an incoming digital audio signal removing the necessity to convert the signal to analog. The output of the modulator is then used to turn the output transistors on and off alternately. Since the transistors are either fully on or fully off, they dissipate very little power. A simple low-pass filter consisting of an inductor and a capacitor provides a path for the low frequencies of the audio signal, leaving the high-frequency pulses behind.
The structure of a class-D power stage is comparable to that of a synchronously rectified buck converter, a type of non-isolated switched-mode power supply (SMPS). Whereas buck converters usually function as voltage regulators, delivering a constant DC voltage into a variable load, and can only source current, a class-D amplifier delivers a constantly changing voltage into a fixed load. A switching amplifier may use any type of power supply (e.g., a car battery or an internal SMPS), but the defining characteristic is that the amplification process itself operates by switching.
The term "class D" is sometimes misunderstood as meaning a "full digital amplifier" (FDA). While some class-D amplifiers may indeed be controlled by digital circuits or include digital signal processing devices, the power stage deals with voltage and current as a function of non-quantized time. The smallest amount of noise, timing uncertainty, voltage ripple or any other non-ideality immediately results in an irreversible change of the output signal. The same errors in a digital system will only lead to incorrect results when they become so large that a signal representing a digit is distorted beyond recognition. Up to that point, non-idealities have no impact on the transmitted signal. Generally, digital signals are quantized in both amplitude and wavelength, while analog signals are quantized in one (e.g. PWM) or (usually) neither quantity.
Hence, my confusion.
What l find interesting is that some of the retailers of these digital amplifiers from Purifi offer different flavours on the input board. Reading the reviews and comparisons the users and barely discern the differences from for example the Ti monolithic Opamp and the Sonic imagery discrete Opamps.
However when comparisons of the Opamps are made with a Headphone Head amp the difference are more obvious.
Putting aside the fact that in the later comparison the listening is done with headphones and not loudspeakers why s this so?
Well if we assume the loudspeaker used in the former comparison was of equivalent accuracy to the headphones this leaves the differences in the transparency of the digital power amplifier and the analogue headphone Headamp.
Chip rolling is a popular means finding the right preference for Head Fi users.
The rational conclusion here is that digital power amplification is not as transparent as a Headphone Headamp.
I am not here putting nails in the coffin for users of digital power amps. Moreover there are approaches to clear thinking which illuminate what a digital power does and doesn’t do in terms of listener subjectivity. Remembering that no two listener necessarily have alike preferences the above illustrates one size does not fit all.
I liken digital power amps modules assembled in a chassis from these vendors like buying a look alike Rolex watch from a street stall in Bali.
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