What are the reasons to choose Class A/AB/H over D in this day and age?

[Willem]

So myopic the viewpoints I’m seeing here.

Why? The story is really simple: it is not about the choice between various ways to save energy, but the need to use all options. And yes, little things matter if enough people use these little things. Of course, there are big things as well, but they are not about audio, which is the focus of this forum.

 

[Willem]

@Willem I am afraid even to ask what kind of "set top box" consumes that much and how much per hour.

Samsung Horizon, 75 watt 24 hours a day. It was supplied by our cable company, and it got so hot that it needed a noisy fan. Many consumers complained so it was phased out after a while.

 

[antennaguru]

A singe data point is not very interesting for the general discussion is it?
We are not talking about Your special amplifier but about amplifier topologys in generals.
Class D is clearly More efficient but how mush this all depends on implementation and the right sizing. Can’t compere a 100W class D with a 25W class A...
Even if this are just penny's for you
It all adds up with 80B. Hunan on this Planet this is maybe you don't care abut an extra "Donut" and the extra emissions and wasted recesses.
This is why there are Regulations for energy efficiency or in other paces taxes on emission. or both.



Sure your comparing it with a class AB with the same power rating?

You must have a reading comprehension issue if you missed the data that ALL four (4) played music at a moderately high volume for their hour. If you need clarification that means the SAME volume over the same speakers EACH.

 

[Golfx]

Has anybody bothered to touch their finger on the output inductor of any Hypex NC500, NC502 or just about any other such module while at idle? That sucker gets hot! Hotter than really any component in an idling class A/B amp. That heat is electricity being consumed, while doing nothing else useful. Just a humble observation.

Are you suggesting class d amps run hot? Vs AB?

 

[anphex]

+What about the preamp you need with the Hypex to use it as a system? Conveniently leaving that out I presume to make the Hypex appear more efficient than the Denon.

Note that my ACTUAL KWH MEASUREMENTS were for an entire minimal system playing for a timed hour and substituting only the four (4) different power amplifiers of different topologies - each for their own hour. This takes away the idle current, peak current, average current uncertainties and gets to the ACTUAL measured power used by each over an hour playing music in a real system.

... I uh... said my Denon (preamp) I use consumes 40 Watt. So nothing left out there. And this thing does HDMI management, room calibration, eARC, network streaming, stuff where some people have separate devices for. And I am sure your devices also need something to feed them...

How many hours of usage per day did you assume in your measurements? If I read correctly you did measure only a time span and extrapolate from there. Whoops nevermind, found it just now.
Edit2: I can very well believe that chip-AB-amps can have a very good efficiency. That too is the point of small semiconductor chips after all. Thinking about it now, the Denon has 9 amps and 45 Watt a drawn additionally, that makes 5 Watt per amp. Same as the Hypex

 

[ZolaIII]

Samsung Horizon, 75 watt 24 hours a day. It was supplied by our cable company, and it got so hot that it needed a noisy fan. Many consumers complained so it was phased out after a while.

While that's epic seams that even a new one is actually rather inefficient (15W per H).

 

[SIY]

Actually, the biggest driver is power output. If you're averaging 1W (say), the differences will be minor. 100W is where you'll see significant differences.

Of course, most of us don't run 100W as an average power for home audio.

 

[MakeMineVinyl]

Are you suggesting class d amps run hot? Vs AB?

I said the output inductor gets very hot, not the entire amplifier. Any component getting that hot in a class A/B amplifier is not common. Note that I'm talking about amplifiers at idle, when efficiency is basically zero.

 

[antennaguru]

We have an energy tax as an incentive to encourage us to save energy for the benefit of the future climate. This is using market forces to move people's behaviour into the socially desirable direction. Since green electricity will be an important component of the energy transition, the tax on natural gas will actually go up in the coming years and the one on electricity will be reduced. Textbook economics.

Oh, so taxing extra to introduce a penalty for not complying with green initiatives is a good solution? How about introducing an actual incentive for lower utilization? Also, what are they doing with that extra taxation they collect?

This concept is like training my dog to do something by a giving her a continuous electric shock through a collar until she complies and finally does it and then turning off the shock, versus just giving her a treat as a reward when she does it. I find the latter more humane but I have seen professional trainers use the former, and claim it’s faster.

 

[pjug]

If I go into the specifics of energy consumption:
One Hypex NC400 monoblack amp draws about 15 Watts. 11 Watt in Idle, so if in heavy use I get about 15 Watt average consumption.
Since I am a heavy user - my system is switched on the second I wake up or come home from work - 8 hours use a day in a week is realistic. The energy cost in Germany is currently about 0,38 € which is 0,43 $. Yup, let that sink in. You'll probably get to this point in the near future too.

So calculating the yearly consumption I get 17,47 € per amp per year. So it's about 35,00 for two.

Now I've seen some older stereo amps A and AB that draw 200 Watt in idle. This would up me to 232,96 € per year. This is more than my air conditioning that literally saves my life during summer lol.

AHB2 spec is 20W idle. Amir measured 18W. I don't know what Outlaw M2200 are but they stay very cool. So comparing power use of newer Class AB G/H amps, power savings would not be nearly so significant.

 

[MakeMineVinyl]

Sure your comparing it with a class AB with the same power rating?

The power rating doesn't matter - do this experiment yourself. Try to keep your finger on the inductor for 10 seconds and report back. For the record though, the amplifiers around me in the factory, class A/B or D are all of similar power; 200-300 watts. The output inductor in a class D amplifier does not have a heatsink, at least in Hypex ones.

 

[Lambda]

class A/B or D are all of similar power; 200-300 watts.

So the Class D your comparing to has about twice the power and your judging from Idle power consumption.
This would be a different sorry if you would put some load on this amplifier.

But it looks like Many here care about energy efficiency.

So it would be nice see @amirm Test for power consumption.
Maybe with Pinknoise and 12dB crest factor and some realistic output like 10W RMS.
into a reactive load of cause

 

[MakeMineVinyl]

So the Class D your comparing to has about twice the power and your judging from Idle power consumption.
This would be a different sorry if you would put some load on this amplifier.

But it looks like Many here care about energy efficiency.

So it would be nice see @amirm Test for power consumption.
Maybe with Pinknoise and 12dB crest factor and some realistic output like 10W RMS.
into a reactive load of cause

You misread me. I said that both the class a b amplifiers and the class D amplifiers are the same power. In any event that doesn't matter just please do the experiment touch your finger to the output inductor of a hypixel amp of any power in the 100-W range or over.

 

[Lambda]

You must have a reading comprehension issue if you missed the data that ALL four (4) played music at a moderately high volume for their hour. If you need clarification that means the SAME volume over the same speakers EACH.

I have.
But you seem to have it to....
If you drive a car with 800Hp and one with 80Hp and you drive at normal hing way speed for an hour i’m very sure the one with the bigger motor will uses more Flue...
So this is not in any way shape or form telling if they have vastly different power ratings.

You misread me. I said that both the class a b amplifiers and the class D amplifiers are the same power.

You said NC502 looked it up it says 1.2kW?
you also said the class d has 200-300W?

the experiment touch your finger to the output inductor of a hypixel amp of any power in the 100-W range or over.

Well i have more sophisticated ways of measuring energy consumption.
And sadly i have no NC502 but my Tpa3116 based amps stay verry cold and uses like 23mA @20V in idle
compared to an TDA2050 with 35mA @20V

So about the same but the class Tpa3116 is 2 channels Full bridge and the TDA2050 is only one channel halve bridged

 

[MakeMineVinyl]

I have.
But you seem to have it to....
If you drive a car with 800Hp and one with 80Hp and you drive at normal hing way speed for an hour i’m very sure the one with the bigger motor will uses more Flue...
So this is not in any way shape or form telling if they have vastly different power ratings.


You said NC502 looked it up it says 1.2kW?
you also said the class d has 200-300W?


Well i have more sophisticated ways of measuring energy consumption.
And sadly i have no NC502 but my Tpa3116 based amps stay verry cold and uses like 23mA @20V in idle
compared to an TDA2050 with 35mA @20V

So about the same but the class Tpa3116 is 2 channels Full bridge and the TDA2050 is only one channel halve bridged

You just keep missing my point. I made a comment that there is power being dissipated in the output inductor. That is a source of waste energy which I have not seen anybody at least here talking about. Regardless of the power rating of the amplifier that's irrelevant to heat disappation in the output inductor. Its dissipating a significant amount of heat regardless of amplifier power rating. You will find the same heating of the output inductor on an MC252 or any similar hypex module. Please, please do this experiment yourself just touch the bloody inductor and tell me if it's hot or not!

 

[Lambda]

Please, please do this experiment yourself just touch the bloody inductor and tell me if it's hot or not!

No my inductors get not hot at all.
but here are different types of class D switching modes.

The output inductor is dissipating a significant amount of heat. You will find the same heating of the output inductor on an MC252 or any similar hypex module. Again the power rating of the module is irrelevant to this waste heat.

What makes you think the module power is irrelevant?!
Bigger Amps in general have more Idle power consumption.

Go ahead and uses halve the input voltage on your module you will notice the inductor gets less worm at idle but you have also less power available.
This shuld show that the Max output power rating is not irrelevant

 

[Twitch54]

I can lower my thermostat when using my Class A amps, saves on my home heating oil bill ..........

 

[ZolaIII]

Well when the manufacturing process differs in couple orders of magnitude (aka transistor vs advanced newer IC) possible applicable isolation/conduction layer (inter stuffing layers) surface shrinks won't say proportionality but almost so such inherit sharper rise in temperature initially when put to load even if they use very little power disregarding of additional cooling (heatsink).

 

[MakeMineVinyl]

No my inductors get not hot at all.
but here are different types of class D switching modes.

What makes you think the module power is irrelevant?!
Bigger Amps in general have more Idle power consumption.

Go ahead and uses halve the input voltage on your module you will notice the inductor gets less worm at idle but you have also less power available.
This shuld show that the Max output power rating is not irrelevant

The amplifier must of course be ON long enough for the inductor to heat up, obviously. And I assume you're touching the correct part.

I'm not attempting to make some grand technical issue here - I'm just pointing out the fact that the output inductor is a surprisingly significant source of waste energy at idle. They all get hot, regardless of power output rating of the amplifier. A lower power amplifier might get a bit less hot than a higher power one, but the point is that they all do this. The switching frequency is being shunted in this inductor, and heat is unavoidable.

Again, my point is that class D is not innocent of wasting some degree of energy. That was my point, and that is the extent of my point.

 

[Lambda]

I can lower my thermostat when using my Class A amps

If you lower the room temperature of cause you get a lower heating bill... but i don't think this is what your trying to say.

Your thermostats regulate a temperature assuming you increases the power output in your room you don't have to lower the thermostat. it will lower the power automatically.

saves on my home heating oil bill

But electricity is normally way more expensive per Kwh compared to burning oil.
But yeah i have changed from LED to good old incandescent for the winter and got my CRT monitors out.

The amplifier must of course be ON long enough for the inductor to heat up, obviously. And I assume you're touching the correct part.

At ~100mW per induktor for my 2*~50W AMP i would need to wait along time...

They all get hot, regardless of power output rating of the amplifier. A lower power amplifier might get a bit less hot than a higher power one, but the point is that they all do this. The switching frequency is being shunted in this inductor, and heat is unavoidable.

Of cause they get hot but not regardless of power output rating

Lower power amplifier might get a bit less hot than a higher power one

This is the point. and this is why it is not regardless of power output rating.