SMPS and Class D Amps in AVRs

MIS100

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Wonder why so very few receivers use switching supplies which are less bulky and more efficient than transformers.

Similarly, Class D Amps also are light weight, more efficient and dissipate a fraction of heat as their Class AB counterparts. Still hardly any AVR manufacturer uses them. Wonder why..
 
Wonder why so very few receivers use switching supplies which are less bulky and more efficient than transformers.

Similarly, Class D Amps also are light weight, more efficient and dissipate a fraction of heat as their Class AB counterparts. Still hardly any AVR manufacturer uses them. Wonder why..

This is one of the many blogs / articles available over Google. It gives some insight and you will also find Youtube videos where experts have explained which class is better:


IMHO, I believe that there is a lot of competition between brands and models. Manufacturers try to put the best under the hood of the AMP/AVR based on market demand and also what is financially / commercially good for all. End of the day, for most of us the quality of components used in an AMP / AVR matter as we like to hear detailed sound from our speakers.
 
Wait for few years, class AB AVRs will phased out. It’s just economics.

Wait for the efficiency policy to kick into audio industry.
And consumer tilt to class D (which is gaining critical mass in advanced consumer markets)


Btw there are already class d AVR.
 
Wait for few years, class AB AVRs will phased out. It’s just economics.

Wait for the efficiency policy to kick into audio industry.
And consumer tilt to class D (which is gaining critical mass in advanced consumer markets)


Btw there are already class d AVR.
If that were the case , how come Class A , tube amps etc which make mincemeat of efficiency , are still around from the dinosaur era ? And still getting made and sold worldwide?
 
If that were the case , how come Class A , tube amps etc which make mincemeat of efficiency , are still around from the dinosaur era ? And still getting made and sold worldwide?
Because humans are sentimental fools and there always will be a market to cater to them. Vinyl is still not dead. There are many who still use mortar and pestel in kitchen believing food is tastier when electric mixer is not used.

You can have a bad Class A amplifier and a good Class D amplifier and vice versa. It all depends on quality sound engineering that goes into making a product.
 
You can have a bad Class A amplifier and a good Class D amplifier and vice versa. It all depends on quality sound engineering that goes into making a product.
Right. It depends on the circuit topology. But till very recent Class D was used for cheap car amplifier where space was premium.
I understand huge improvements have been made in Class D , however personally I’m yet to hear one that sounds musical. So I’ll reserve my judgements.

Regarding your first comment, I’ll beg to totally differ. Sentiment and nostalgia alone cannot account for what you are claiming. If that were so , how come CRT TVs haven’t made a revival ? Why are VCRs not being made anymore ?
Or for that matter - why don’t we have nostalgialaden Ambassadors and Maruti 800s out on the streets ?

It’s a fact analog playback through vinyl sounds mindblowingly good , and beats a digital setup many times pricier , especially if you listen to pre 1990s stuff. Even for contemporary music where it’s digital end to end from recording ,mixing to mastering , a vinyl sounds better than CD or streaming.
Just take any Adele LP and compare with its CD or streaming counterpart.
I listen to both LPs and CDs and this has been my observation.
I’m pretty sure you haven’t heard a properly setup vinyl rig , hence you cannot understand why vinyls have come back from the dead.

PS : Top chefs from Gordon Ramsey to Marco Pierre prefer hand crushing spices than using mixers. They do know a bit more about food than you or me , don’t they ? :)
 
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Wonder why so very few receivers use switching supplies which are less bulky and more efficient than transformers.

Similarly, Class D Amps also are light weight, more efficient and dissipate a fraction of heat as their Class AB counterparts. Still hardly any AVR manufacturer uses them. Wonder why..
There may be many possible reasons for this, most of them are non-technology related.
From a business sense, AVRs focus more on audio and video processing rather than amplification.
This aspect is a very fast changing scenario with advancements in technology and formats.

Class A/B is a tried and tested design with discrete components.
- this means a company can keep using a proven design in a wide variety of product lines (aka cookie cutting)
- the core of the amplifier is not tied to chips/semiconductors from a specific company which usually requires multi year contracts

There are companies that are shifting to class D, but only in their premium/niche range.
Eg. NAD, recently Marantz
In a few years, when the cost and procurement of class D modules matures, you will start seeing this tech more and more in AVRs.
Good class D, which does not sound "thin/lean" is still expensive. They are designed by a handful of companies as of now.

The modules that are used in ICE systems or TVs are low power systems, in the range of say 10-40W.
AVRs need a bit more output power from the amp section since they will mate with commercially available speaker systems.
These clean sounding, high power modules are not cheap or light or small footprint, as of today.

Cheers,
Raghu
 
PS : Top chefs from Gordon Ramsey to Marco Pierre prefer hand crushing spices than using mixers. They do know a bit more about food than you or me , don’t they ? :)
Exactly the point I was making. Sentimental fools. If the top chef says something, disregard your own tongue which says otherwise and adopt an alien taste and do what the top chef says, what the crowd says. Herd Mentality.:):p
 
Exactly the point I was making. Sentimental fools. If the top chef says something, disregard your own tongue which says otherwise and adopt an alien taste and do what the top chef says, what the crowd says. Herd Mentality.:):p
Ha ha ha … I see whoever doesn’t subscribe to your notion of what sounds good or tastes good belong to the herd mentality.
I haven’t listened to a high end Class D amp- so I had reserved my judgements.

Try to experience a well setup vinyl rig from some of the FMs in Pune or Mumbai. You will eat your own words. :)
 
Times are a changing.


Just wait for purifi to get mainstream. Then and there debate will be over
There is no debate. Audiophiles don’t care for Class A or Class D or Class G. They care for good sound. If the newer NADs or Marantz Class D sound good , there will be buyers. Likewise proven designs from Class A , A/B will continue selling as well.
 
Ha ha ha … I see whoever doesn’t subscribe to your notion of what sounds good or tastes good belong to the herd mentality.

Try to experience a well setup vinyl rig from some of the FMs in Pune or Mumbai. You will eat your own words. Come to Kolkata and I’ll be happy to host you. :)
I have 3 vinyl rig and I love them especially the old Jazz records and Hindi vinyl from the 50s and 60s. But I believe HMV (now saregama) screwed up when they converted these to digital from the vinyl and tape masters. It is a marvel that the humble record players can play so well. Digital has its own set of problems (which many believe are no longer a problem - jitter, noise, etc). But that doesn't mean that vinyl is the best. If you have an excellent source, digital will sound better. Other is the valve amps (which I too have them) with pleasant harmonic distortions. As far as I'm concerned, I prefer my humble < Rs 10000 Class D allo amp better than the valve because it gives a more honest reproduction of the source. There are many other things that I have learned the hard way after spending money and cables is a very good example where all you require is totally neutral cable. A neutral cable is one with 0 resistance, 0 capacitance and 0 inductance so that the frequency response will be linear throughout the human audio spectrum. I have discarded each of my cables and now use my self made cables with less than 10 pF capacitance per meter. I prefer to be objective and avoid anything voodoo that is ascribed to sounds people hear with cables, cable risers, cable cookers, isolation feets for amps, etc.
 
I have 3 vinyl rig and I love them especially the old Jazz records and Hindi vinyl from the 50s and 60s. But I believe HMV (now saregama) screwed up when they converted these to digital from the vinyl and tape masters. It is a marvel that the humble record players can play so well. Digital has its own set of problems (which many believe are no longer a problem - jitter, noise, etc). But that doesn't mean that vinyl is the best. If you have an excellent source, digital will sound better. Other is the valve amps (which I too have them) with pleasant harmonic distortions. As far as I'm concerned, I prefer my humble < Rs 10000 Class D allo amp better than the valve because it gives a more honest reproduction of the source. There are many other things that I have learned the hard way after spending money and cables is a very good example where all you require is totally neutral cable. A neutral cable is one with 0 resistance, 0 capacitance and 0 inductance so that the frequency response will be linear throughout the human audio spectrum. I have discarded each of my cables and now use my self made cables with less than 10 pF capacitance per meter. I prefer to be objective and avoid anything voodoo that is ascribed to sounds people hear with cables, cable risers, cable cookers, isolation feets for amps, etc.
Very true(the bold part ).
Since HMV (Saregama ) screwed up massively the digital conversions of thousands of Hindi songs from their catalog from 1950s to 1980s , be that for whatever reasons (many master tapes are damaged beyond repair in fires ) - the original (first pressing ) vinyls for retro hindi film music still sounds leagues better than the best version of CDs- that’s fairly easy to understand.

It still doesn’t explain why contemporary music sounds better on vinyl than on CDs with excellent digital sources , and the only reason that comes up is mastering on CDs are heavily compressed which is not the case for vinyl mastering.
I have compared several mainstream contemporary popular albums on vinyls and first edition CDs. Vinyl playback sounds markedly better.
 
Times are a changing.


Just wait for purifi to get mainstream. Then and there debate will be over

Indeed and the herd of sheep will change their direction

There is no debate. Audiophiles don’t care for Class A or Class D or Class G. They care for good sound. If the newer NADs or Marantz Class D sound good , there will be buyers. Likewise proven designs from Class A , A/B will continue selling as well.

Every advancement in audio or video does not need to throw out the old tech.
There is a place for some old and beaten concepts even today, in the audio world.

For those who are stuck in their tracks, please try the following in your audio journey towards bliss or efficiency.
- listen to a mainstream class A amp (Pass, CJ, McIntosh, etc)
- listen to a mainstream class A/B amp (Parasound, Marantz/Denon, Rotel, Rega, etc)
- listen to a mainstream class D amp (NAD Masters, ICE/Purifi/nCore based etc)
- listen to a simple TT setup
- listen to a simple tube setup (even if it is flea watt)
Remember it is a journey, we can only host this much at our homes.
But this doesn't mean the end of the experience. If we think this way, we are only limiting what we can possibly listen to.

Cheers,
Raghu
 
Wonder why so very few receivers use switching supplies which are less bulky and more efficient than transformers.

Similarly, Class D Amps also are light weight, more efficient and dissipate a fraction of heat as their Class AB counterparts. Still hardly any AVR manufacturer uses them. Wonder why..
Pioneer is one company that had introduced Class D amps in their AVRs some 8-10 years ago. It took them quite some time to bring the AVRs to the mainframe, but they have achieved that over the last 4-5 years time. In addition to excellent sound, they also offer better efficiency, more power, and other features for the same price of competing companies.

With companies such as Purufi, IcePower and others bringing Class D to the main frame, it is only a matter of time that all AVRs switch to Class D. Companies such as Denon, Marantz and will just redesign their AVRs to fit on the amp modules. Of course, right now these modules are expensive. No company can spend $500 per channel for just amplification, when their whole 7.2 is between 500-2500$. Like NAD did, some company may also just get the technology and build multi-channel amps themselves. I am sure engineers are burning midnight oil to get a solution to these issues.

For movies, a good Class D will be far better in terms of sound quality, power and sheer dynamics needed.

One of the best combination is a multi-channel processor attached to a multi-channel power amp. If you use Emotiva for the processor, this should cost around 2000$ in the non-Indian market. Marantz has also come out will small units that does just processing.

Cheers
 
There is no debate. Audiophiles don’t care for Class A or Class D or Class G. They care for good sound. If the newer NADs or Marantz Class D sound good , there will be buyers. Likewise proven designs from Class A , A/B will continue selling as well.
C'mon....you know that's not true.
Audiophiles, most of them, vouch that Class A amps are the best 'audiophilic amp topology'.....and most of the resistance against class D has been in comparison to Class A.

After all massive tank like class A amps with bullet proof thick heatsinks with massive toroidal transformer looks more esoteric and justifiable than a puny class D amp with smps power. ;)
 
Pioneer is one company that had introduced Class D amps in their AVRs some 8-10 years ago. It took them quite some time to bring the AVRs to the mainframe, but they have achieved that over the last 4-5 years time. In addition to excellent sound, they also offer better efficiency, more power, and other features for the same price of competing companies.

With companies such as Purufi, IcePower and others bringing Class D to the main frame, it is only a matter of time that all AVRs switch to Class D. Companies such as Denon, Marantz and will just redesign their AVRs to fit on the amp modules. Of course, right now these modules are expensive. No company can spend $500 per channel for just amplification, when their whole 7.2 is between 500-2500$. Like NAD did, some company may also just get the technology and build multi-channel amps themselves. I am sure engineers are burning midnight oil to get a solution to these issues.

For movies, a good Class D will be far better in terms of sound quality, power and sheer dynamics needed.

One of the best combination is a multi-channel processor attached to a multi-channel power amp. If you use Emotiva for the processor, this should cost around 2000$ in the non-Indian market. Marantz has also come out will small units that does just processing.

Cheers
Cannot disagree.

There is a reason the pro market have such for cinema

 
C'mon....you know that's not true.
Audiophiles, most of them, vouch that Class A amps are the best 'audiophilic amp topology'.....and most of the resistance against class D has been in comparison to Class A.

After all massive tank like class A amps with bullet proof thick heatsinks with massive toroidal transformer looks more esoteric and justifiable than a puny class D amp with smps power. ;)
Why do you always leap to conclusions that are not there?
A music enthusiast will recount his/her experience based on what they have listened to and experienced.
It so happens, that some of them like a particular amp topology or DAC implementation or measured performance.
These are still opinions not hard facts. One may take it on faith or with a bag of salt.

For some the experience or topology matters, no matter what the measurements are.
For others the measurements matter, no matter what the experience is.
Neither is complete in isolation.

Coming to class A amps, what's the deal about them?
- they produce heat and rake up electricity bills
- they are bulky and heavy
- they measure horribly

And speaking of Class D amps, what's their deal?
- efficient
- loads of power
- great measurements

Are these the criteria that a user should base their decision to buy or not?
Should it not be about how they sound in an audio rig and how they drive speakers to make the user feel the music?
There are products that will appeal to each and everyone of us. Some more than others.
Keep an open mind and ear.

Disclosure:
If I have the opportunity:
- class A preamp/poweramp combo for music
- AV pre-processor with good class D amplification for HT
- a simple TT setup with a flea-watt tube setup and OB speakers
Unfortunately, none of the above are possible in my home.
Doesn't mean they are not worth listening to. And I would definitely not go about disparaging them.

Cheers,
Raghu
 
Why do you always leap to conclusions that are not there?
A music enthusiast will recount his/her experience based on what they have listened to and experienced.
It so happens, that some of them like a particular amp topology or DAC implementation or measured performance.
These are still opinions not hard facts. One may take it on faith or with a bag of salt.

For some the experience or topology matters, no matter what the measurements are.
For others the measurements matter, no matter what the experience is.
Neither is complete in isolation.

Coming to class A amps, what's the deal about them?
- they produce heat and rake up electricity bills
- they are bulky and heavy
- they measure horribly

And speaking of Class D amps, what's their deal?
- efficient
- loads of power
- great measurements

Are these the criteria that a user should base their decision to buy or not?
Should it not be about how they sound in an audio rig and how they drive speakers to make the user feel the music?
There are products that will appeal to each and everyone of us. Some more than others.
Keep an open mind and ear.

Disclosure:
If I have the opportunity:
- class A preamp/poweramp combo for music
- AV pre-processor with good class D amplification for HT
- a simple TT setup with a flea-watt tube setup and OB speakers
Unfortunately, none of the above are possible in my home.
Doesn't mean they are not worth listening to. And I would definitely not go about disparaging them.

Cheers,
Raghu
I have came across many hifi forums.....not just about HFV. And my comment was due to the generalisation from these forums. And many a threads in HFV also implied the better sonic capabilities of Class A.

Btw it's not a 'personal' insinuation particularly targeted to you. It's a general statement of audiophiles as a cohort/population.
 
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