Audiophiles, generally don't like class D amps!

[DarkKoala]

I think I‘m pretty critical to those audiophiles.
As a child and young adult I sourced my digital music through hmmmm some means. Also didn’t have the means to buy the high end gear. I remember thinking 1000€ for speakers was unachievable huge amount of money for that.

My first amp as student was the cheapest 5.1 100W written on the box I could find: Something from MCVoice (yeah actual brand) whatever… I think it was digital with it I drove the speakers given to me free. Then I bought a Marantz PM62 used…. was great. Then had to move and gave away cd player, amp, and speakers to a buddy and bought a Project Stereobox s with psb alpha b1 and using the pc as source. Was acceptable. Then got a Project Maia DS… well that was the last time I used a digital amp. My research back then let me to a realization that the couple of hundred euros amp uses some cheap modules for couple of bucks from AliExpress. Also had some weird issues. Since then use „in my mind: normal“ amp.

Now 10 years later, technology has progressed, no doubt. But now have a working system and don’t feel the need to change. The amp is just there to drive my speakers. I listen to music not gear. And now since I‘m actually buying my cds and records and digital downloads, this also costs a lot of money, maybe more than the actual gear.

It‘s not that I avoid digital amps, just a pita to get one and can not justify the cost, ofc I‘m not going to downgrade. Maybe some other also had similar experiences.

 

[zorox]

I think I‘m pretty critical to those audiophiles.
As a child and young adult I sourced my digital music through hmmmm some means. Also didn’t have the means to buy the high end gear. I remember thinking 1000€ for speakers was unachievable huge amount of money for that.

My first amp as student was the cheapest 5.1 100W written on the box I could find: Something from MCVoice (yeah actual brand) whatever… I think it was digital with it I drove the speakers given to me free. Then I bought a Marantz PM62 used…. was great. Then had to move and gave away cd player, amp, and speakers to a buddy and bought a Project Stereobox s with psb alpha b1 and using the pc as source. Was acceptable. Then got a Project Maia DS… well that was the last time I used a digital amp. My research back then let me to a realization that the couple of hundred euros amp uses some cheap modules for couple of bucks from AliExpress. Also had some weird issues. Since then use „in my mind: normal“ amp.

Now 10 years later, technology has progressed, no doubt. But now have a working system and don’t feel the need to change. The amp is just there to drive my speakers. I listen to music not gear. And now since I‘m actually buying my cds and records and digital downloads, this also costs a lot of money, maybe more than the actual gear.

It‘s not that I avoid digital amps, just a pita to get one and can not justify the cost, ofc I‘m not going to downgrade. Maybe some other also had similar

Off topic.

 

[SIY]

I think I‘m pretty critical to those audiophiles.
As a child and young adult I sourced my digital music through hmmmm some means. Also didn’t have the means to buy the high end gear. I remember thinking 1000€ for speakers was unachievable huge amount of money for that.

My first amp as student was the cheapest 5.1 100W written on the box I could find: Something from MCVoice (yeah actual brand) whatever… I think it was digital with it I drove the speakers given to me free. Then I bought a Marantz PM62 used…. was great. Then had to move and gave away cd player, amp, and speakers to a buddy and bought a Project Stereobox s with psb alpha b1 and using the pc as source. Was acceptable. Then got a Project Maia DS… well that was the last time I used a digital amp. My research back then let me to a realization that the couple of hundred euros amp uses some cheap modules for couple of bucks from AliExpress. Also had some weird issues. Since then use „in my mind: normal“ amp.

Now 10 years later, technology has progressed, no doubt. But now have a working system and don’t feel the need to change. The amp is just there to drive my speakers. I listen to music not gear. And now since I‘m actually buying my cds and records and digital downloads, this also costs a lot of money, maybe more than the actual gear.

It‘s not that I avoid digital amps, just a pita to get one and can not justify the cost, ofc I‘m not going to downgrade. Maybe some other also had similar experiences.

What’s a “digital amp?”

 

[egellings]

Benchmark is not classD

I think Benchmark uses a switch-mode power supply to power class AB amplifiers. Works like a charm.

 

[Theta]

I think Benchmark uses a switch-mode power supply to power class AB amplifiers. Works like a charm.

Benchmark is a class H amplifier

 

[Waxx]

Benchmark is a class H amplifier

And class H is a class AB with an advanced variable rail voltage switching power supply where the voltage supplied to the amp module is always right fit for the signal (so less heat losses). The amplifier module itself is class AB with feedforward error correction (does the same as negative feedback, but better says Benchmark) and on it's own is not that special or revolutionairy, it's based on basic systems that are already decades in use on a large scale. The difference is made in the power supply and the execution. So in essence it's an advanced class AB like all class G or H amplifiers are, but one that is very well designed and executed.

Bryston did and does still do something similar, but less good. They have long been the favorite amps in studio's because they are so clean low distortion, also wth an ABH type of layout, but with a linear psu and a lot of voltage regulation and filtering to get that variablevoltage rail system. They used to be at least one of the best, but are surpased now by many modern class D designs (Hypex, Purifi, even Icepower), and some class AB designs like the Benchmark ABH, often for a fraction of the price.

 

[Theta]

And class H is a class AB with an advanced variable rail voltage switching power supply where the voltage supplied to the amp module is always right fit for the signal (so less heat losses). The amplifier module itself is class AB with feedforward error correction (does the same as negative feedback, but better says Benchmark) and on it's own is not that special or revolutionairy, it's based on basic systems that are already decades in use on a large scale. The difference is made in the power supply and the execution. So in essence it's an advanced class AB like all class G or H amplifiers are, but one that is very well designed and executed.

Bryston did and does still do something similar, but less good. They have long been the favorite amps in studio's because they are so clean low distortion, also wth an ABH type of layout, but with a linear psu and a lot of voltage regulation and filtering to get that variablevoltage rail system. They used to be at least one of the best, but are surpased now by many modern class D designs (Hypex, Purifi, even Icepower), and some class AB designs like the Benchmark ABH, often for a fraction of the price.

Surpassed how?

 

[egellings]

And class H is a class AB with an advanced variable rail voltage switching power supply where the voltage supplied to the amp module is always right fit for the signal (so less heat losses). The amplifier module itself is class AB with feedforward error correction (does the same as negative feedback, but better says Benchmark) and on it's own is not that special or revolutionairy, it's based on basic systems that are already decades in use on a large scale. The difference is made in the power supply and the execution. So in essence it's an advanced class AB like all class G or H amplifiers are, but one that is very well designed and executed.

Bryston did and does still do something similar, but less good. They have long been the favorite amps in studio's because they are so clean low distortion, also wth an ABH type of layout, but with a linear psu and a lot of voltage regulation and filtering to get that variablevoltage rail system. They used to be at least one of the best, but are surpased now by many modern class D designs (Hypex, Purifi, even Icepower), and some class AB designs like the Benchmark ABH, often for a fraction of the price.

Agree. The configuration of the devices is class H, but the devices themselves can operate in class A, AB or B while in the class H configuration.

 

[EJ3]

And class H is a class AB with an advanced variable rail voltage switching power supply where the voltage supplied to the amp module is always right fit for the signal (so less heat losses). The amplifier module itself is class AB with feedforward error correction (does the same as negative feedback, but better says Benchmark) and on it's own is not that special or revolutionairy, it's based on basic systems that are already decades in use on a large scale. The difference is made in the power supply and the execution. So in essence it's an advanced class AB like all class G or H amplifiers are, but one that is very well designed and executed.

Bryston did and does still do something similar, but less good. They have long been the favorite amps in studio's because they are so clean low distortion, also wth an ABH type of layout, but with a linear psu and a lot of voltage regulation and filtering to get that variablevoltage rail system. They used to be at least one of the best, but are surpased now by many modern class D designs (Hypex, Purifi, even Icepower), and some class AB designs like the Benchmark ABH, often for a fraction of the price.

As my NAD 2200's are CLASS G, run cool, have a 95 SINAD (through the lab inputs [at least the one that Amir tested {thank you again}) and I have no reason to think that any of my others have less. The power consumption is low, the heat is low, they can be repaired easily, I see absolutely no reason to change amps at this time.
Price: initial purchase price in the mid-80's (my first 3) + resto-modding refurbishments, puts me at about $1000 a unit. So $3000 amortized over 38 years= $79.95 a year. Or $6.58 a month.
The difference between their power consumption and a CLASS D (unless you leave them on 24/7) for an average of 2 hours a day is negligible.
And I have complied in being green by no wholesale getting rid of electronics into the environment.
Hot Rodders of old cars/people who repair/reuse/repurpose/resto-mod/update are the original ENVIRONMENTALISTS (actually conservationists) since environmentalism has such a negative connotation these days (what with environmental terrorism, PETA and other outrageous stunts).

 

[egellings]

Agree. The configuration of the devices is class H, but the devices themselves can operate in class A, AB or B while in the class H configuration.

Class H is a connection scheme. Class AB and the rest refer to where the devices are operated on their characteristic electrical curves or graphs.

 

[EJ3]

Class H is a connection scheme. Class AB and the rest refer to where the devices are operated on their characteristic electrical curves or graphs.

I thought that the point of this is that one is supposedly more "GREEN" than the other. through wastes when building, power consumption to end of life disposal.
Since, over more than 30 years, mine have used almost as low power consumption and I have yet to put mine in the landfill (even though a few parts have gone to the landfill), the "GREENESS" of my NAD 2200's is yet to be determined.

 

[egellings]

With class D there is more circuit complexity, although components used in them tend to be small. AB and the others need larger components such as heavy transformers, but are simpler with smaller component counts. Pick your poison. In operation, D wins hands down efficiency-wise. Over the long haul, D will win in overall efficiency when those years of low power consumption use add up.

 

[voodooless]

AB and the others need larger components such as heavy transformers

AB amps don’t need transformers, it’s just that traditionally the power supplies had them. You can replace them with an SMPS just fine. Chances are they will even perform better

With class D there is more circuit complexity

With discrete design, generally yes, but the chipamps can be quite simple and only use a few handfuls of components. Some AB chipamps may be even simpler (gainclones) and can be point to point soldered. With class D, that is not a good idea.

If you want top performance, though, complexity goes up fast, regardless of Class.

 

[Sal1950]

What’s a “digital amp?”

Oh you know, it amplifies with the same staircase effect to the power output level, in the same way digital music chops up the frequency response.

 

[Broadcast_Eng]

And class H is a class AB with an advanced variable rail voltage switching power supply where the voltage supplied to the amp module is always right fit for the signal (so less heat losses). The amplifier module itself is class AB with feedforward error correction (does the same as negative feedback, but better says Benchmark) and on it's own is not that special or revolutionairy, it's based on basic systems that are already decades in use on a large scale. The difference is made in the power supply and the execution. So in essence it's an advanced class AB like all class G or H amplifiers are, but one that is very well designed and executed.

Bryston did and does still do something similar, but less good. They have long been the favorite amps in studio's because they are so clean low distortion, also wth an ABH type of layout, but with a linear psu and a lot of voltage regulation and filtering to get that variablevoltage rail system. They used to be at least one of the best, but are surpased now by many modern class D designs (Hypex, Purifi, even Icepower), and some class AB designs like the Benchmark ABH, often for a fraction of the price.

I believe I'm reasonably familiar with Bryston products and their design philosophy, and have schematics for many of their power amplifiers through the 'SST' generation. I am unaware of anything other than fixed (but unregulated) voltage rails supporting their amplifiers' output stages.

That, of course, might have changed with their current ('Cubed') generation of amplifiers, but I have been unable to find a single reference suggesting a significant change of their output topology. Please point me toward any information you're aware of that might suggest otherwise.

 

[egellings]

AB amps don’t need transformers, it’s just that traditionally the power supplies had them. You can replace them with an SMPS just fine. Chances are they will even perform better

With discrete design, generally yes, but the chipamps can be quite simple and only use a few handfuls of components. Some AB chipamps may be even simpler (gainclones) and can be point to point soldered. With class D, that is not a good idea.

If you want top performance, though, complexity goes up fast, regardless of Class.

By transformers I meant power ones, since an SS amp and a few room heater direct coupled tube amps need no output transformer. As far as I know, all amps use some sort of a power transformer, be it a big iron one in a conventional 50/60Hz supply or a little walnut sized one in a switchmode supply. You'd want that transformer there just for galvanic isolation from the dangerous power line, if nothing else.

 

[mhardy6647]

What’s a “digital amp?”

I don't know either, but it would be ideal for playing one of those good old data cassettes from the early days of "modern personal computing"
Bzzzzzz...BZZZZZZ...bzz..bzz...bzz...BZZZZZZZZZZZZZ...bzzzz...bz...bz...bz...BZZZZZZZZZZZZZZZZZ...bzzzzzzzzzzzz...

 

[voodooless]

As far as I know, all amps use some sort of a power transformer, be it a big iron one in a conventional 50/60Hz supply or a little walnut sized one in a switchmode supply.

Yes, an SMPS obviously also has a transformer That’s still not something specific to AB amps though, as you already mentioned.

 

[Sal1950]

I don't know either

Can't believe that dude bothered to record all those crazy digital handshake sounds.
He seems like the ultimate computer nerd. LOL

 

[egellings]

Yes, an SMPS obviously also has a transformer That’s still not something specific to AB amps though, as you already mentioned.

DC to D.C. Converters may not need a power transformer if isolation is not needed. As an example a PCB may have 5V components and , say, 3.3V ones on it, and a non isolating buck type converter can be used there.