NEWS: Technics premieres SU-R1000 Reference Class integrated amplifier

Cliff

Distinguished Member
So plenty of pseudo technical gobbledygook. Basic fact not stated, is it class D ?
 

LAMitchell

Active Member
Well, reading, it sounds as though Technics are embracing the digital world plus retro look. It reminds me a little of the Luxman L-509x Integrated amp in looks and price, I would be intrigued to see how it performs side by side as it seems to be pushing a lot on using digital technology to remove the distortion vs Luxman keep it clean and direct approach.
 

Ugg10

Distinguished Member
Looks like Class D (lists PCM conversion) with a switch mode power supply (Quoting a switching frequency). I suspect it is an evolution of /alternative to the Hypex/Icepower/NCore/Purifi/Arcam G Class technology that is starting to pop up in most line ups and seems to be getting good reviews and measure very well (assuming you like low distortion with good delivery into most speakers down to 2 ohms).
 

Cliff

Distinguished Member
I think the clue is talk of PWM (pulse width modulation)..

As for all the flowery talk around the SMPSU, all it has to do is provide a stable output with current reserves. The clock can be fixed, (and synched with other clocks) no big deal, but most importantly the PSU will be in a screened box, so no spurious frequencies get into the audio side.

Anyway, I am sure the specs are good, but it is a high price to pay, when considerable savings are made going down the switch mode psu and class D route. No large transformer and no massive heatsinks for the output stages.
 

stjernholm

Active Member
Its a Digital amplifier, not a Class-D. Whole different ballgame. Same tech as used in the reference class R1 system, but in a lighter and cheaper package.

The amp packs many brand new features (not found elsewhere) that is exciting, like a digitally processed phono stage that corrects crosstalk and impedans (using a test record for calibration), "out of this world" battery driven jitter reduction engine, and active distortion cancelling. I want one!
 

DT79

Well-known Member
I do hope they create a standalone phono stage based on that same technology.
 

Welwynnick

Distinguished Member
Its a Digital amplifier, not a Class-D. Whole different ballgame. Same tech as used in the reference class R1 system, but in a lighter and cheaper package.
It's good to see manufacturers being up front about the technology they use, even if they do seem to be re-inventing the wheel here, and calling it an Infinitely Recycling Axial Support Sub-system.

So yes, they do call it a digital amplifier, but in what way is that not class D? The usual argument is that class D isn't digital, which always seemed very peculiar to me, but this is the other way round.

Nick
 
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DT79

Well-known Member
It's good to see manufacturers being up front about the technology they use, even if they do seem to be re-inventing the wheel here, and calling it an Infinitely Recycling Axial Support Sub-system.

So yes, they do call it a digital amplifier, but in what way is that not class D? The usual argument is that class D isn't digital, which always seemed very peculiar to me, but this is the other way round.

Nick
It probably is class D, but it appears they haven't specified that. Class D is not inherently analogue or digital, I think is the point. Class D designs can be either.
 

Welwynnick

Distinguished Member
How can class D be analogue? The output transistors are either ON or OFF!

Class A/B/C/D refers to the biasing configuration of the output transistors and the way the output waveform is generated, and the characteristics of the amplifier reflects the different bias configs.

Class D means that the output transistor is operated either fully on or fully off, just like a switch, so it's state can be represented as 0 or 1. That is what digital means, therefore class D is digital.

When marketing spin doctors describe class D as analogue, I think they mean the pulse width control is analogue. Therefore the transistors are opened and closed for a variable duration, rather than for a number of cycles.

Fair enough, but that's orthogonal to the bias configuration, and it's the bias configuration that determines the amplifier characteristics - efficiency, distortion, bandwidth, etc. A class D amp with linear PWM control is still a class D amp, and that's what primarily determines it's characteristics - square wave output, low pass filter, high efficiency, etc. Both linear and digital control of the pulse width still exhibit all of those characteristics.

Nick
 
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dannnielll

Well-known Member
How can class D be analogue? The output transistors are either ON or OFF!

Class A/B/C/D refers to the biasing configuration of the output transistors and the way the output waveform is generated, and the characteristics of the amplifier reflects the different bias configs.

Class D means that the output transistor is operated either fully on or fully off, just like a switch, so it's state can be represented as 0 or 1. That is what digital means, therefore class D is digital.

When marketing spin doctors describe class D as analogue, I think they mean the pulse width control is analogue. Therefore the transistors are opened and closed for a variable duration, rather than for a number of cycles.

Fair enough, but that's orthogonal to the bias configuration, and it's the bias configuration that determines the amplifier characteristics - efficiency, distortion, bandwidth, etc. A class D amp with linear PWM control is still a class D amp, and that's what primarily determines it's characteristics - square wave output, low pass filter, high efficiency, etc. Both linear and digital control of the pulse width still exhibit all of those characteristics.

Nick
It is not just a case of semantics. I have never been a fan of the term digital ..it is basically meaningless, and much prefer the French numerical or numerique.. but the proper term for a device using on /off control is switching.... Or as you say Class D . A DAC is a numerical control device ,and a Class D device could be under full analogue control.. yes feedback??? Or numerical control or even zero control . I would have less difficulty if the letter D referred to Discrete .as opposed to continuous
 

DT79

Well-known Member
How can class D be analogue? The output transistors are either ON or OFF!

Class A/B/C/D refers to the biasing configuration of the output transistors and the way the output waveform is generated, and the characteristics of the amplifier reflects the different bias configs.

Class D means that the output transistor is operated either fully on or fully off, just like a switch, so it's state can be represented as 0 or 1. That is what digital means, therefore class D is digital.

When marketing spin doctors describe class D as analogue, I think they mean the pulse width control is analogue. Therefore the transistors are opened and closed for a variable duration, rather than for a number of cycles.

Fair enough, but that's orthogonal to the bias configuration, and it's the bias configuration that determines the amplifier characteristics - efficiency, distortion, bandwidth, etc. A class D amp with linear PWM control is still a class D amp, and that's what primarily determines it's characteristics - square wave output, low pass filter, high efficiency, etc. Both linear and digital control of the pulse width still exhibit all of those characteristics.

Nick
It is not just a case of semantics. I have never been a fan of the term digital ..it is basically meaningless, and much prefer the French numerical or numerique.. but the proper term for a device using on /off control is switching.... Or as you say Class D . A DAC is a numerical control device ,and a Class D device could be under full analogue control.. yes feedback??? Or numerical control or even zero control . I would have less difficulty if the letter D referred to Discrete .as opposed to continuous

What he said :)
 

stjernholm

Active Member
Digital amplifiers are designed to be fed directly by digital rather than analog signals. They make direct use of this signal—without any DAC circuitry whatsoever—to drive the power stage. Robert Harley explains:

As with Class D amplifiers, digital amplifiers use a switching output stage; however, they accept digital rather than analog input signals. These “digital” amplifiers take in the pulse-code modulation (PCM) signal from a music server or other source and convert those audio data to a pulse-width modulated signal. This PWM signal then drives the output transistors, just as in a Class D amplifier. The difference between a Class D amplifier and a digital amplifier is that the digital amplifier accepts digital data rather than an analog signal.

This difference might not seem that great at first glance, but consider the signal path of a conventional digital-playback chain driving a Class D—or any other traditional—power amplifier. Your digital source feeds audio data to a DAC that converts the digital data to an analog signal; the DAC’s current output is converted to a voltage by a current-to-voltage converter; the signal is low-pass filtered, then amplified in the DAC’s analog-output stage. This analog output signal travels down interconnects to a preamplifier with its several stages of amplification, volume control, and output buffer. The preamp’s output then travels down another pair of interconnects to the power amplifier, which typically employs an input stage, a driver stage, and the Class D output stage. In addition to the D/A conversion, that’s typically six or seven active amplification stages before the signal gets to the power amplifier’s output stage.

To reiterate the contrast with a true digital amplifier, PCM data are converted by DSP into the PWM signal that drives the output transistors. That’s it. There are no analog gain stages between the PCM data and your loudspeakers. The signal stays in the digital domain until the switching output stage, which, by its nature, acts as a digital-to-analog converter in concert with the amplifier’s output filter. The volume is adjusted in DSP. Digital amplifiers are usually not just power amplifiers, but also include a range of inputs, source selection, and volume control, effectively giving them the functional capabilities of an integrated amplifier.
 

stjernholm

Active Member
It's good to see manufacturers being up front about the technology they use, even if they do seem to be re-inventing the wheel here, and calling it an Infinitely Recycling Axial Support Sub-system.

So yes, they do call it a digital amplifier, but in what way is that not class D? The usual argument is that class D isn't digital, which always seemed very peculiar to me, but this is the other way round.

Nick

Digital amplifiers are designed to be fed directly by digital rather than analog signals. They make direct use of this signal—without any DAC circuitry whatsoever—to drive the power stage. Robert Harley explains:

As with Class D amplifiers, digital amplifiers use a switching output stage; however, they accept digital rather than analog input signals. These “digital” amplifiers take in the pulse-code modulation (PCM) signal from a music server or other source and convert those audio data to a pulse-width modulated signal. This PWM signal then drives the output transistors, just as in a Class D amplifier. The difference between a Class D amplifier and a digital amplifier is that the digital amplifier accepts digital data rather than an analog signal.

This difference might not seem that great at first glance, but consider the signal path of a conventional digital-playback chain driving a Class D—or any other traditional—power amplifier. Your digital source feeds audio data to a DAC that converts the digital data to an analog signal; the DAC’s current output is converted to a voltage by a current-to-voltage converter; the signal is low-pass filtered, then amplified in the DAC’s analog-output stage. This analog output signal travels down interconnects to a preamplifier with its several stages of amplification, volume control, and output buffer. The preamp’s output then travels down another pair of interconnects to the power amplifier, which typically employs an input stage, a driver stage, and the Class D output stage. In addition to the D/A conversion, that’s typically six or seven active amplification stages before the signal gets to the power amplifier’s output stage.

To reiterate the contrast with a true digital amplifier, PCM data are converted by DSP into the PWM signal that drives the output transistors. That’s it. There are no analog gain stages between the PCM data and your loudspeakers. The signal stays in the digital domain until the switching output stage, which, by its nature, acts as a digital-to-analog converter in concert with the amplifier’s output filter. The volume is adjusted in DSP. Digital amplifiers are usually not just power amplifiers, but also include a range of inputs, source selection, and volume control, effectively giving them the functional capabilities of an integrated amplifier.
 

Welwynnick

Distinguished Member
I'm not mocking digital amplifiers, I'm an advocate of them. In fact I own one of the greatest pure digital amplifiers ever made - the Sony TA-DA9100ES. It's a Japan-only model that's very difficult and expensive to get into this country, but does exactly what you describe - an all digital path from input to the output stage, and only becomes analogue in the (passive) output low pass filter.

With a digital source, there's no active analogue processing anywhere. My view is that audio equipment generally succeeds or fails in their A-to-D and D-to-A stages, and the DA9100 doesn't have any.


I don't know whether the Technics SU-R1000 will achieve the same, but I think the results would be worth it. You can argue about whether you have a power DAC and no amp, or a digital amp and no DAC, and keep yourselves amused for a while....

What gets me though, is how people take perfectly good digital technology and then try to disguise it as something else, trying to side-step some of the negative perceptions and connotations. Some people seem to think that digital audio gives you a signal comprised of staircases of digital steps, which is completely wrong.

[/SOAPBOX]

Nick
 

DT79

Well-known Member
What gets me though, is how people take perfectly good digital technology and then try to disguise it as something else, trying to side-step some of the negative perceptions and connotations. Some people seem to think that digital audio gives you a signal comprised of staircases of digital steps, which is completely wrong.
As a Lyngdorf owner it won’t surprise you to know that I’m in complete agreement with your views on digital amps. However I genuinely don’t believe that a class d amp should be regarded as inherently digital or analogue. Granted the output transistors are either on or off, but fed an analogue signal, the switching frequency is sufficiently high that the analogue waveform is maintained in all its resolution. If you call that digital, you have to question whether there is really any such thing as analogue at all.

What defines the maximum resolution of a vinyl front end? The size of the stylus versus the minimum size of fluctuation in the groove wall of the record. The stylus is either small enough to track it, or it isn’t, but the whole system is defined by that absolute binary factor.

Even the way sound moves through the air could be questioned. The air is either moving/pressurised (beyond ambient background factors) or it’s not.

I would say that for any component to be regarded as ‘digital’ it has to be acting upon a musical signal which is in a digitised form and not an analogue waveform.
 

dannnielll

Well-known Member
As a Lyngdorf owner it won’t surprise you to know that I’m in complete agreement with your views on digital amps. However I genuinely don’t believe that a class d amp should be regarded as inherently digital or analogue. Granted the output transistors are either on or off, but fed an analogue signal, the switching frequency is sufficiently high that the analogue waveform is maintained in all its resolution. If you call that digital, you have to question whether there is really any such thing as analogue at all.

What defines the maximum resolution of a vinyl front end? The size of the stylus versus the minimum size of fluctuation in the groove wall of the record. The stylus is either small enough to track it, or it isn’t, but the whole system is defined by that absolute binary factor.

Even the way sound moves through the air could be questioned. The air is either moving/pressurised (beyond ambient background factors) or it’s not.

I would say that for any component to be regarded as ‘digital’ it has to be acting upon a musical signal which is in a digitised form and not an analogue waveform.
The distinction is that a system is analogue if the measured parameter .. voltage or current has a value analogous or directly proportional to the instantaneous value of the signal.
 

DT79

Well-known Member
The distinction is that a system is analogue if the measured parameter .. voltage or current has a value analogous or directly proportional to the instantaneous value of the signal.
Thanks, that’s what I was trying to get at, much less articulately.
 

dannnielll

Well-known Member
Thanks, that’s what I was trying to get at, much less articulately.
..if after 35 years teaching the subject ,I couldn't express myself, I would have been hopeless
 

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